ETH Price: $2,612.34 (-0.62%)

Transaction Decoder

Block:
16963144 at Apr-02-2023 06:21:23 PM +UTC
Transaction Fee:
0.003477506003279784 ETH $9.08
Gas Used:
179,046 Gas / 19.422416604 Gwei

Emitted Events:

208 Elevate.Transfer( from=[Sender] 0xcb7c9824d0739b9877a797eaeba4da7fe9f764fc, to=0x7122db0Ebe4EB9B434a9F2fFE6760BC03BFbD0E0, value=2631345530640241019083279 )
209 Elevate.Approval( owner=0x7122db0Ebe4EB9B434a9F2fFE6760BC03BFbD0E0, spender=Vault, value=2631345530640241019083279 )
210 Vault.Swap( poolId=652E3CDC80F4697EECD8046BE9D21DCA5B1C30DC0002000000000000000004EF, tokenIn=Elevate, tokenOut=WETH9, amountIn=2631345530640241019083279, amountOut=2166845394769426803 )
211 Elevate.Transfer( from=0x7122db0Ebe4EB9B434a9F2fFE6760BC03BFbD0E0, to=Vault, value=2631345530640241019083279 )
212 Elevate.Approval( owner=0x7122db0Ebe4EB9B434a9F2fFE6760BC03BFbD0E0, spender=Vault, value=0 )
213 WETH9.Transfer( src=Vault, dst=0x7122db0Ebe4EB9B434a9F2fFE6760BC03BFbD0E0, wad=2166845394769426803 )
214 WETH9.Withdrawal( src=0x7122db0Ebe4EB9B434a9F2fFE6760BC03BFbD0E0, wad=2166845394769426803 )

Account State Difference:

  Address   Before After State Difference Code
0x045109cF...54a1aEA65
(builder0x69)
3.040821704032119423 Eth3.040860571632330093 Eth0.00003886760021067
0xBA122222...d566BF2C8
(Balancer: Vault)
0xC02aaA39...83C756Cc2 3,796,214.311958859605090827 Eth3,796,212.145113464835664024 Eth2.166845394769426803
0xCb7c9824...FE9f764FC
2.019721475607099861 Eth
Nonce: 9
4.18308936437324688 Eth
Nonce: 10
2.163367888766147019

Execution Trace

AggregationRouterV5.swap( executor=0x7122db0Ebe4EB9B434a9F2fFE6760BC03BFbD0E0, desc=[{name:srcToken, type:address, order:1, indexed:false, value:0x045109cF1Be9eDEC048AA0B3D7a323154a1aEA65, valueString:0x045109cF1Be9eDEC048AA0B3D7a323154a1aEA65}, {name:dstToken, type:address, order:2, indexed:false, value:0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE, valueString:0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE}, {name:srcReceiver, type:address, order:3, indexed:false, value:0x7122db0Ebe4EB9B434a9F2fFE6760BC03BFbD0E0, valueString:0x7122db0Ebe4EB9B434a9F2fFE6760BC03BFbD0E0}, {name:dstReceiver, type:address, order:4, indexed:false, value:0xCb7c9824D0739B9877A797eaEbA4dA7FE9f764FC, valueString:0xCb7c9824D0739B9877A797eaEbA4dA7FE9f764FC}, {name:amount, type:uint256, order:5, indexed:false, value:2631345530640241019083279, valueString:2631345530640241019083279}, {name:minReturnAmount, type:uint256, order:6, indexed:false, value:1105111733849979776, valueString:1105111733849979776}, {name:flags, type:uint256, order:7, indexed:false, value:4, valueString:4}], permit=0x, data=0x0000000000000000000000000000000000000000000000A100008B00004F00A0FBB7CD0600652E3CDC80F4697EECD8046BE9D21DCA5B1C30DC0002000000000000000004EF045109CF1BE9EDEC048AA0B3D7A323154A1AEA65C02AAA39B223FE8D0A0E5C4F27EAD9083C756CC24101C02AAA39B223FE8D0A0E5C4F27EAD9083C756CC200042E1A7D4D0000000000000000000000000000000000000000000000000000000000000000C0611111111254EEB25477B68FB85ED929F73A960582 ) => ( returnAmount=2166845394769426803, spentAmount=2631345530640241019083279 )
  • Elevate.transferFrom( sender=0xCb7c9824D0739B9877A797eaEbA4dA7FE9f764FC, recipient=0x7122db0Ebe4EB9B434a9F2fFE6760BC03BFbD0E0, amount=2631345530640241019083279 ) => ( True )
  • 0x7122db0ebe4eb9b434a9f2ffe6760bc03bfbd0e0.4b64e492( )
    • 0x7122db0ebe4eb9b434a9f2ffe6760bc03bfbd0e0.fbb7cd06( )
      • Elevate.approve( spender=0xBA12222222228d8Ba445958a75a0704d566BF2C8, amount=2631345530640241019083279 ) => ( True )
      • Vault.swap( singleSwap=[{name:poolId, type:bytes32, order:1, indexed:false, value:652E3CDC80F4697EECD8046BE9D21DCA5B1C30DC0002000000000000000004EF, valueString:652E3CDC80F4697EECD8046BE9D21DCA5B1C30DC0002000000000000000004EF}, {name:kind, type:uint8, order:2, indexed:false, value:0, valueString:0}, {name:assetIn, type:address, order:3, indexed:false, value:0x045109cF1Be9eDEC048AA0B3D7a323154a1aEA65, valueString:0x045109cF1Be9eDEC048AA0B3D7a323154a1aEA65}, {name:assetOut, type:address, order:4, indexed:false, value:0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2, valueString:0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2}, {name:amount, type:uint256, order:5, indexed:false, value:2631345530640241019083279, valueString:2631345530640241019083279}, {name:userData, type:bytes, order:6, indexed:false, value:0x, valueString:0x}], funds=[{name:sender, type:address, order:1, indexed:false, value:0x7122db0Ebe4EB9B434a9F2fFE6760BC03BFbD0E0, valueString:0x7122db0Ebe4EB9B434a9F2fFE6760BC03BFbD0E0}, {name:fromInternalBalance, type:bool, order:2, indexed:false, value:false, valueString:False}, {name:recipient, type:address, order:3, indexed:false, value:0x7122db0Ebe4EB9B434a9F2fFE6760BC03BFbD0E0, valueString:0x7122db0Ebe4EB9B434a9F2fFE6760BC03BFbD0E0}, {name:toInternalBalance, type:bool, order:4, indexed:false, value:false, valueString:False}], limit=0, deadline=1680459683 ) => ( amountCalculated=2166845394769426803 )
        • NoProtocolFeeLiquidityBootstrappingPool.onSwap( request=[{name:kind, type:uint8, order:1, indexed:false, value:0, valueString:0}, {name:tokenIn, type:address, order:2, indexed:false, value:0x045109cF1Be9eDEC048AA0B3D7a323154a1aEA65, valueString:0x045109cF1Be9eDEC048AA0B3D7a323154a1aEA65}, {name:tokenOut, type:address, order:3, indexed:false, value:0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2, valueString:0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2}, {name:amount, type:uint256, order:4, indexed:false, value:2631345530640241019083279, valueString:2631345530640241019083279}, {name:poolId, type:bytes32, order:5, indexed:false, value:652E3CDC80F4697EECD8046BE9D21DCA5B1C30DC0002000000000000000004EF, valueString:652E3CDC80F4697EECD8046BE9D21DCA5B1C30DC0002000000000000000004EF}, {name:lastChangeBlock, type:uint256, order:6, indexed:false, value:16963100, valueString:16963100}, {name:from, type:address, order:7, indexed:false, value:0x7122db0Ebe4EB9B434a9F2fFE6760BC03BFbD0E0, valueString:0x7122db0Ebe4EB9B434a9F2fFE6760BC03BFbD0E0}, {name:to, type:address, order:8, indexed:false, value:0x7122db0Ebe4EB9B434a9F2fFE6760BC03BFbD0E0, valueString:0x7122db0Ebe4EB9B434a9F2fFE6760BC03BFbD0E0}, {name:userData, type:bytes, order:9, indexed:false, value:0x, valueString:0x}], balanceTokenIn=1847215385633849517329117311, balanceTokenOut=86336821698548064945 ) => ( 2166845394769426803 )
        • Elevate.transferFrom( sender=0x7122db0Ebe4EB9B434a9F2fFE6760BC03BFbD0E0, recipient=0xBA12222222228d8Ba445958a75a0704d566BF2C8, amount=2631345530640241019083279 ) => ( True )
        • WETH9.transfer( dst=0x7122db0Ebe4EB9B434a9F2fFE6760BC03BFbD0E0, wad=2166845394769426803 ) => ( True )
        • WETH9.withdraw( wad=2166845394769426803 )
          • ETH 2.166845394769426803 0x7122db0ebe4eb9b434a9f2ffe6760bc03bfbd0e0.CALL( )
          • ETH 2.166845394769426803 AggregationRouterV5.CALL( )
          • ETH 2.166845394769426803 0xcb7c9824d0739b9877a797eaeba4da7fe9f764fc.CALL( )
            File 1 of 5: AggregationRouterV5
            /*
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                                11\   11\                     11\             11\   11\            11\                                       11\
                              1111 |  \__|                    11 |            111\  11 |           11 |                                      11 |
                              \_11 |  11\ 1111111\   1111111\ 1111111\        1111\ 11 | 111111\ 111111\   11\  11\  11\  111111\   111111\  11 |  11\
                                11 |  11 |11  __11\ 11  _____|11  __11\       11 11\11 |11  __11\\_11  _|  11 | 11 | 11 |11  __11\ 11  __11\ 11 | 11  |
                                11 |  11 |11 |  11 |11 /      11 |  11 |      11 \1111 |11111111 | 11 |    11 | 11 | 11 |11 /  11 |11 |  \__|111111  /
                                11 |  11 |11 |  11 |11 |      11 |  11 |      11 |\111 |11   ____| 11 |11\ 11 | 11 | 11 |11 |  11 |11 |      11  _11<
                              111111\ 11 |11 |  11 |\1111111\ 11 |  11 |      11 | \11 |\1111111\  \1111  |\11111\1111  |\111111  |11 |      11 | \11\
                              \______|\__|\__|  \__| \_______|\__|  \__|      \__|  \__| \_______|  \____/  \_____\____/  \______/ \__|      \__|  \__|
            
            
            
                                           111111\                                                               11\     11\
                                          11  __11\                                                              11 |    \__|
                                          11 /  11 | 111111\   111111\   111111\   111111\   111111\   111111\ 111111\   11\  111111\  1111111\
                                          11111111 |11  __11\ 11  __11\ 11  __11\ 11  __11\ 11  __11\  \____11\\_11  _|  11 |11  __11\ 11  __11\
                                          11  __11 |11 /  11 |11 /  11 |11 |  \__|11111111 |11 /  11 | 1111111 | 11 |    11 |11 /  11 |11 |  11 |
                                          11 |  11 |11 |  11 |11 |  11 |11 |      11   ____|11 |  11 |11  __11 | 11 |11\ 11 |11 |  11 |11 |  11 |
                                          11 |  11 |\1111111 |\1111111 |11 |      \1111111\ \1111111 |\1111111 | \1111  |11 |\111111  |11 |  11 |
                                          \__|  \__| \____11 | \____11 |\__|       \_______| \____11 | \_______|  \____/ \__| \______/ \__|  \__|
                                                    11\   11 |11\   11 |                    11\   11 |
                                                    \111111  |\111111  |                    \111111  |
                                                     \______/  \______/                      \______/
                                                            1111111\                        11\
                                                            11  __11\                       11 |
                                                            11 |  11 | 111111\  11\   11\ 111111\    111111\   111111\
                                                            1111111  |11  __11\ 11 |  11 |\_11  _|  11  __11\ 11  __11\
                                                            11  __11< 11 /  11 |11 |  11 |  11 |    11111111 |11 |  \__|
                                                            11 |  11 |11 |  11 |11 |  11 |  11 |11\ 11   ____|11 |
                                                            11 |  11 |\111111  |\111111  |  \1111  |\1111111\ 11 |
                                                            \__|  \__| \______/  \______/    \____/  \_______|\__|
            */
            
            // SPDX-License-Identifier: MIT
            
            // File contracts/interfaces/IClipperExchangeInterface.sol
            
            
            pragma solidity 0.8.17;
            
            /// @title Clipper interface subset used in swaps
            interface IClipperExchangeInterface {
                struct Signature {
                    uint8 v;
                    bytes32 r;
                    bytes32 s;
                }
            
                function sellEthForToken(address outputToken, uint256 inputAmount, uint256 outputAmount, uint256 goodUntil, address destinationAddress, Signature calldata theSignature, bytes calldata auxiliaryData) external payable;
                function sellTokenForEth(address inputToken, uint256 inputAmount, uint256 outputAmount, uint256 goodUntil, address destinationAddress, Signature calldata theSignature, bytes calldata auxiliaryData) external;
                function swap(address inputToken, address outputToken, uint256 inputAmount, uint256 outputAmount, uint256 goodUntil, address destinationAddress, Signature calldata theSignature, bytes calldata auxiliaryData) external;
            }
            
            
            // File contracts/helpers/RouterErrors.sol
            
            
            pragma solidity 0.8.17;
            
            library RouterErrors {
                error ReturnAmountIsNotEnough();
                error InvalidMsgValue();
                error ERC20TransferFailed();
            }
            
            
            // File @1inch/solidity-utils/contracts/[email protected]
            
            
            pragma solidity ^0.8.0;
            
            abstract contract EthReceiver {
                error EthDepositRejected();
            
                receive() external payable {
                    _receive();
                }
            
                function _receive() internal virtual {
                    // solhint-disable-next-line avoid-tx-origin
                    if (msg.sender == tx.origin) revert EthDepositRejected();
                }
            }
            
            
            // File @openzeppelin/contracts/token/ERC20/[email protected]
            
            // OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol)
            
            pragma solidity ^0.8.0;
            
            /**
             * @dev Interface of the ERC20 standard as defined in the EIP.
             */
            interface IERC20 {
                /**
                 * @dev Emitted when `value` tokens are moved from one account (`from`) to
                 * another (`to`).
                 *
                 * Note that `value` may be zero.
                 */
                event Transfer(address indexed from, address indexed to, uint256 value);
            
                /**
                 * @dev Emitted when the allowance of a `spender` for an `owner` is set by
                 * a call to {approve}. `value` is the new allowance.
                 */
                event Approval(address indexed owner, address indexed spender, uint256 value);
            
                /**
                 * @dev Returns the amount of tokens in existence.
                 */
                function totalSupply() external view returns (uint256);
            
                /**
                 * @dev Returns the amount of tokens owned by `account`.
                 */
                function balanceOf(address account) external view returns (uint256);
            
                /**
                 * @dev Moves `amount` tokens from the caller's account to `to`.
                 *
                 * Returns a boolean value indicating whether the operation succeeded.
                 *
                 * Emits a {Transfer} event.
                 */
                function transfer(address to, uint256 amount) external returns (bool);
            
                /**
                 * @dev Returns the remaining number of tokens that `spender` will be
                 * allowed to spend on behalf of `owner` through {transferFrom}. This is
                 * zero by default.
                 *
                 * This value changes when {approve} or {transferFrom} are called.
                 */
                function allowance(address owner, address spender) external view returns (uint256);
            
                /**
                 * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
                 *
                 * Returns a boolean value indicating whether the operation succeeded.
                 *
                 * IMPORTANT: Beware that changing an allowance with this method brings the risk
                 * that someone may use both the old and the new allowance by unfortunate
                 * transaction ordering. One possible solution to mitigate this race
                 * condition is to first reduce the spender's allowance to 0 and set the
                 * desired value afterwards:
                 * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
                 *
                 * Emits an {Approval} event.
                 */
                function approve(address spender, uint256 amount) external returns (bool);
            
                /**
                 * @dev Moves `amount` tokens from `from` to `to` using the
                 * allowance mechanism. `amount` is then deducted from the caller's
                 * allowance.
                 *
                 * Returns a boolean value indicating whether the operation succeeded.
                 *
                 * Emits a {Transfer} event.
                 */
                function transferFrom(
                    address from,
                    address to,
                    uint256 amount
                ) external returns (bool);
            }
            
            
            // File @1inch/solidity-utils/contracts/interfaces/[email protected]
            
            
            pragma solidity ^0.8.0;
            
            
            interface IDaiLikePermit {
                function permit(address holder, address spender, uint256 nonce, uint256 expiry, bool allowed, uint8 v, bytes32 r, bytes32 s) external;
            }
            
            
            // File @1inch/solidity-utils/contracts/libraries/[email protected]
            
            
            pragma solidity ^0.8.0;
            
            library RevertReasonForwarder {
                function reRevert() internal pure {
                    // bubble up revert reason from latest external call
                    /// @solidity memory-safe-assembly
                    assembly { // solhint-disable-line no-inline-assembly
                        let ptr := mload(0x40)
                        returndatacopy(ptr, 0, returndatasize())
                        revert(ptr, returndatasize())
                    }
                }
            }
            
            
            // File @openzeppelin/contracts/token/ERC20/extensions/[email protected]
            
            // OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/draft-IERC20Permit.sol)
            
            pragma solidity ^0.8.0;
            
            /**
             * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
             * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
             *
             * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
             * presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't
             * need to send a transaction, and thus is not required to hold Ether at all.
             */
            interface IERC20Permit {
                /**
                 * @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,
                 * given ``owner``'s signed approval.
                 *
                 * IMPORTANT: The same issues {IERC20-approve} has related to transaction
                 * ordering also apply here.
                 *
                 * Emits an {Approval} event.
                 *
                 * Requirements:
                 *
                 * - `spender` cannot be the zero address.
                 * - `deadline` must be a timestamp in the future.
                 * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
                 * over the EIP712-formatted function arguments.
                 * - the signature must use ``owner``'s current nonce (see {nonces}).
                 *
                 * For more information on the signature format, see the
                 * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
                 * section].
                 */
                function permit(
                    address owner,
                    address spender,
                    uint256 value,
                    uint256 deadline,
                    uint8 v,
                    bytes32 r,
                    bytes32 s
                ) external;
            
                /**
                 * @dev Returns the current nonce for `owner`. This value must be
                 * included whenever a signature is generated for {permit}.
                 *
                 * Every successful call to {permit} increases ``owner``'s nonce by one. This
                 * prevents a signature from being used multiple times.
                 */
                function nonces(address owner) external view returns (uint256);
            
                /**
                 * @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}.
                 */
                // solhint-disable-next-line func-name-mixedcase
                function DOMAIN_SEPARATOR() external view returns (bytes32);
            }
            
            
            // File @1inch/solidity-utils/contracts/libraries/[email protected]
            
            
            pragma solidity ^0.8.0;
            
            
            
            
            library SafeERC20 {
                error SafeTransferFailed();
                error SafeTransferFromFailed();
                error ForceApproveFailed();
                error SafeIncreaseAllowanceFailed();
                error SafeDecreaseAllowanceFailed();
                error SafePermitBadLength();
            
                // Ensures method do not revert or return boolean `true`, admits call to non-smart-contract
                function safeTransferFrom(IERC20 token, address from, address to, uint256 amount) internal {
                    bytes4 selector = token.transferFrom.selector;
                    bool success;
                    /// @solidity memory-safe-assembly
                    assembly { // solhint-disable-line no-inline-assembly
                        let data := mload(0x40)
            
                        mstore(data, selector)
                        mstore(add(data, 0x04), from)
                        mstore(add(data, 0x24), to)
                        mstore(add(data, 0x44), amount)
                        success := call(gas(), token, 0, data, 100, 0x0, 0x20)
                        if success {
                            switch returndatasize()
                            case 0 { success := gt(extcodesize(token), 0) }
                            default { success := and(gt(returndatasize(), 31), eq(mload(0), 1)) }
                        }
                    }
                    if (!success) revert SafeTransferFromFailed();
                }
            
                // Ensures method do not revert or return boolean `true`, admits call to non-smart-contract
                function safeTransfer(IERC20 token, address to, uint256 value) internal {
                    if (!_makeCall(token, token.transfer.selector, to, value)) {
                        revert SafeTransferFailed();
                    }
                }
            
                // If `approve(from, to, amount)` fails, try to `approve(from, to, 0)` before retry
                function forceApprove(IERC20 token, address spender, uint256 value) internal {
                    if (!_makeCall(token, token.approve.selector, spender, value)) {
                        if (!_makeCall(token, token.approve.selector, spender, 0) ||
                            !_makeCall(token, token.approve.selector, spender, value))
                        {
                            revert ForceApproveFailed();
                        }
                    }
                }
            
                function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
                    uint256 allowance = token.allowance(address(this), spender);
                    if (value > type(uint256).max - allowance) revert SafeIncreaseAllowanceFailed();
                    forceApprove(token, spender, allowance + value);
                }
            
                function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
                    uint256 allowance = token.allowance(address(this), spender);
                    if (value > allowance) revert SafeDecreaseAllowanceFailed();
                    forceApprove(token, spender, allowance - value);
                }
            
                function safePermit(IERC20 token, bytes calldata permit) internal {
                    bool success;
                    if (permit.length == 32 * 7) {
                        success = _makeCalldataCall(token, IERC20Permit.permit.selector, permit);
                    } else if (permit.length == 32 * 8) {
                        success = _makeCalldataCall(token, IDaiLikePermit.permit.selector, permit);
                    } else {
                        revert SafePermitBadLength();
                    }
                    if (!success) RevertReasonForwarder.reRevert();
                }
            
                function _makeCall(IERC20 token, bytes4 selector, address to, uint256 amount) private returns(bool success) {
                    /// @solidity memory-safe-assembly
                    assembly { // solhint-disable-line no-inline-assembly
                        let data := mload(0x40)
            
                        mstore(data, selector)
                        mstore(add(data, 0x04), to)
                        mstore(add(data, 0x24), amount)
                        success := call(gas(), token, 0, data, 0x44, 0x0, 0x20)
                        if success {
                            switch returndatasize()
                            case 0 { success := gt(extcodesize(token), 0) }
                            default { success := and(gt(returndatasize(), 31), eq(mload(0), 1)) }
                        }
                    }
                }
            
                function _makeCalldataCall(IERC20 token, bytes4 selector, bytes calldata args) private returns(bool success) {
                    /// @solidity memory-safe-assembly
                    assembly { // solhint-disable-line no-inline-assembly
                        let len := add(4, args.length)
                        let data := mload(0x40)
            
                        mstore(data, selector)
                        calldatacopy(add(data, 0x04), args.offset, args.length)
                        success := call(gas(), token, 0, data, len, 0x0, 0x20)
                        if success {
                            switch returndatasize()
                            case 0 { success := gt(extcodesize(token), 0) }
                            default { success := and(gt(returndatasize(), 31), eq(mload(0), 1)) }
                        }
                    }
                }
            }
            
            
            // File @1inch/solidity-utils/contracts/interfaces/[email protected]
            
            
            pragma solidity ^0.8.0;
            
            interface IWETH is IERC20 {
                function deposit() external payable;
                function withdraw(uint256 amount) external;
            }
            
            
            // File contracts/routers/ClipperRouter.sol
            
            
            pragma solidity 0.8.17;
            
            
            
            
            
            
            /// @title Clipper router that allows to use `ClipperExchangeInterface` for swaps
            contract ClipperRouter is EthReceiver {
                using SafeERC20 for IERC20;
            
                uint256 private constant _SIGNATURE_S_MASK = 0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff;
                uint256 private constant _SIGNATURE_V_SHIFT = 255;
                bytes6 private constant _INCH_TAG_WITH_LENGTH_PREFIX = "\x051INCH";
                IERC20 private constant _ETH = IERC20(address(0));
                IWETH private immutable _WETH;  // solhint-disable-line var-name-mixedcase
            
                constructor(IWETH weth) {
                    _WETH = weth;
                }
            
                /// @notice Same as `clipperSwapTo` but calls permit first,
                /// allowing to approve token spending and make a swap in one transaction.
                /// @dev See tests for examples
                /// @param recipient Address that will receive swap funds
                /// @param srcToken Source token
                /// @param dstToken Destination token
                /// @param inputAmount Amount of source tokens to swap
                /// @param outputAmount Amount of destination tokens to receive
                /// @param goodUntil Timestamp until the swap will be valid
                /// @param r Clipper order signature (r part)
                /// @param vs Clipper order signature (vs part)
                /// @param permit Should contain valid permit that can be used in `IERC20Permit.permit` calls.
                /// @return returnAmount Amount of destination tokens received
                function clipperSwapToWithPermit(
                    IClipperExchangeInterface clipperExchange,
                    address payable recipient,
                    IERC20 srcToken,
                    IERC20 dstToken,
                    uint256 inputAmount,
                    uint256 outputAmount,
                    uint256 goodUntil,
                    bytes32 r,
                    bytes32 vs,
                    bytes calldata permit
                ) external returns(uint256 returnAmount) {
                    srcToken.safePermit(permit);
                    return clipperSwapTo(clipperExchange, recipient, srcToken, dstToken, inputAmount, outputAmount, goodUntil, r, vs);
                }
            
                /// @notice Same as `clipperSwapTo` but uses `msg.sender` as recipient
                /// @param srcToken Source token
                /// @param dstToken Destination token
                /// @param inputAmount Amount of source tokens to swap
                /// @param outputAmount Amount of destination tokens to receive
                /// @param goodUntil Timestamp until the swap will be valid
                /// @param r Clipper order signature (r part)
                /// @param vs Clipper order signature (vs part)
                /// @return returnAmount Amount of destination tokens received
                function clipperSwap(
                    IClipperExchangeInterface clipperExchange,
                    IERC20 srcToken,
                    IERC20 dstToken,
                    uint256 inputAmount,
                    uint256 outputAmount,
                    uint256 goodUntil,
                    bytes32 r,
                    bytes32 vs
                ) external payable returns(uint256 returnAmount) {
                    return clipperSwapTo(clipperExchange, payable(msg.sender), srcToken, dstToken, inputAmount, outputAmount, goodUntil, r, vs);
                }
            
                /// @notice Performs swap using Clipper exchange. Wraps and unwraps ETH if required.
                /// Sending non-zero `msg.value` for anything but ETH swaps is prohibited
                /// @param recipient Address that will receive swap funds
                /// @param srcToken Source token
                /// @param dstToken Destination token
                /// @param inputAmount Amount of source tokens to swap
                /// @param outputAmount Amount of destination tokens to receive
                /// @param goodUntil Timestamp until the swap will be valid
                /// @param r Clipper order signature (r part)
                /// @param vs Clipper order signature (vs part)
                /// @return returnAmount Amount of destination tokens received
                function clipperSwapTo(
                    IClipperExchangeInterface clipperExchange,
                    address payable recipient,
                    IERC20 srcToken,
                    IERC20 dstToken,
                    uint256 inputAmount,
                    uint256 outputAmount,
                    uint256 goodUntil,
                    bytes32 r,
                    bytes32 vs
                ) public payable returns(uint256 returnAmount) {
                    bool srcETH = srcToken == _ETH;
                    if (srcETH) {
                        if (msg.value != inputAmount) revert RouterErrors.InvalidMsgValue();
                    } else if (srcToken == _WETH) {
                        srcETH = true;
                        if (msg.value != 0) revert RouterErrors.InvalidMsgValue();
                        // _WETH.transferFrom(msg.sender, address(this), inputAmount);
                        // _WETH.withdraw(inputAmount);
                        address weth = address(_WETH);
                        bytes4 transferFromSelector = _WETH.transferFrom.selector;
                        bytes4 withdrawSelector = _WETH.withdraw.selector;
                        /// @solidity memory-safe-assembly
                        assembly { // solhint-disable-line no-inline-assembly
                            let ptr := mload(0x40)
            
                            mstore(ptr, transferFromSelector)
                            mstore(add(ptr, 0x04), caller())
                            mstore(add(ptr, 0x24), address())
                            mstore(add(ptr, 0x44), inputAmount)
                            if iszero(call(gas(), weth, 0, ptr, 0x64, 0, 0)) {
                                returndatacopy(ptr, 0, returndatasize())
                                revert(ptr, returndatasize())
                            }
            
                            mstore(ptr, withdrawSelector)
                            mstore(add(ptr, 0x04), inputAmount)
                            if iszero(call(gas(), weth, 0, ptr, 0x24, 0, 0)) {
                                returndatacopy(ptr, 0, returndatasize())
                                revert(ptr, returndatasize())
                            }
                        }
                    } else {
                        if (msg.value != 0) revert RouterErrors.InvalidMsgValue();
                        srcToken.safeTransferFrom(msg.sender, address(clipperExchange), inputAmount);
                    }
            
                    if (srcETH) {
                        // clipperExchange.sellEthForToken{value: inputAmount}(address(dstToken), inputAmount, outputAmount, goodUntil, recipient, signature, _INCH_TAG);
                        address clipper = address(clipperExchange);
                        bytes4 selector = clipperExchange.sellEthForToken.selector;
                        /// @solidity memory-safe-assembly
                        assembly { // solhint-disable-line no-inline-assembly
                            let ptr := mload(0x40)
            
                            mstore(ptr, selector)
                            mstore(add(ptr, 0x04), dstToken)
                            mstore(add(ptr, 0x24), inputAmount)
                            mstore(add(ptr, 0x44), outputAmount)
                            mstore(add(ptr, 0x64), goodUntil)
                            mstore(add(ptr, 0x84), recipient)
                            mstore(add(ptr, 0xa4), add(27, shr(_SIGNATURE_V_SHIFT, vs)))
                            mstore(add(ptr, 0xc4), r)
                            mstore(add(ptr, 0xe4), and(vs, _SIGNATURE_S_MASK))
                            mstore(add(ptr, 0x104), 0x120)
                            mstore(add(ptr, 0x143), _INCH_TAG_WITH_LENGTH_PREFIX)
                            if iszero(call(gas(), clipper, inputAmount, ptr, 0x149, 0, 0)) {
                                returndatacopy(ptr, 0, returndatasize())
                                revert(ptr, returndatasize())
                            }
                        }
                    } else if (dstToken == _ETH || dstToken == _WETH) {
                        // clipperExchange.sellTokenForEth(address(srcToken), inputAmount, outputAmount, goodUntil, recipient, signature, _INCH_TAG);
                        address clipper = address(clipperExchange);
                        bytes4 selector = clipperExchange.sellTokenForEth.selector;
                        /// @solidity memory-safe-assembly
                        assembly { // solhint-disable-line no-inline-assembly
                            let ptr := mload(0x40)
            
                            mstore(ptr, selector)
                            mstore(add(ptr, 0x04), srcToken)
                            mstore(add(ptr, 0x24), inputAmount)
                            mstore(add(ptr, 0x44), outputAmount)
                            mstore(add(ptr, 0x64), goodUntil)
                            switch iszero(dstToken)
                            case 1 {
                                mstore(add(ptr, 0x84), recipient)
                            }
                            default {
                                mstore(add(ptr, 0x84), address())
                            }
                            mstore(add(ptr, 0xa4), add(27, shr(_SIGNATURE_V_SHIFT, vs)))
                            mstore(add(ptr, 0xc4), r)
                            mstore(add(ptr, 0xe4), and(vs, _SIGNATURE_S_MASK))
                            mstore(add(ptr, 0x104), 0x120)
                            mstore(add(ptr, 0x143), _INCH_TAG_WITH_LENGTH_PREFIX)
                            if iszero(call(gas(), clipper, 0, ptr, 0x149, 0, 0)) {
                                returndatacopy(ptr, 0, returndatasize())
                                revert(ptr, returndatasize())
                            }
                        }
            
                        if (dstToken == _WETH) {
                            // _WETH.deposit{value: outputAmount}();
                            // _WETH.transfer(recipient, outputAmount);
                            address weth = address(_WETH);
                            bytes4 depositSelector = _WETH.deposit.selector;
                            bytes4 transferSelector = _WETH.transfer.selector;
                            /// @solidity memory-safe-assembly
                            assembly { // solhint-disable-line no-inline-assembly
                                let ptr := mload(0x40)
            
                                mstore(ptr, depositSelector)
                                if iszero(call(gas(), weth, outputAmount, ptr, 0x04, 0, 0)) {
                                    returndatacopy(ptr, 0, returndatasize())
                                    revert(ptr, returndatasize())
                                }
            
                                mstore(ptr, transferSelector)
                                mstore(add(ptr, 0x04), recipient)
                                mstore(add(ptr, 0x24), outputAmount)
                                if iszero(call(gas(), weth, 0, ptr, 0x44, 0, 0)) {
                                    returndatacopy(ptr, 0, returndatasize())
                                    revert(ptr, returndatasize())
                                }
                            }
                        }
                    } else {
                        // clipperExchange.swap(address(srcToken), address(dstToken), inputAmount, outputAmount, goodUntil, recipient, signature, _INCH_TAG);
                        address clipper = address(clipperExchange);
                        bytes4 selector = clipperExchange.swap.selector;
                        /// @solidity memory-safe-assembly
                        assembly { // solhint-disable-line no-inline-assembly
                            let ptr := mload(0x40)
            
                            mstore(ptr, selector)
                            mstore(add(ptr, 0x04), srcToken)
                            mstore(add(ptr, 0x24), dstToken)
                            mstore(add(ptr, 0x44), inputAmount)
                            mstore(add(ptr, 0x64), outputAmount)
                            mstore(add(ptr, 0x84), goodUntil)
                            mstore(add(ptr, 0xa4), recipient)
                            mstore(add(ptr, 0xc4), add(27, shr(_SIGNATURE_V_SHIFT, vs)))
                            mstore(add(ptr, 0xe4), r)
                            mstore(add(ptr, 0x104), and(vs, _SIGNATURE_S_MASK))
                            mstore(add(ptr, 0x124), 0x140)
                            mstore(add(ptr, 0x163), _INCH_TAG_WITH_LENGTH_PREFIX)
                            if iszero(call(gas(), clipper, 0, ptr, 0x169, 0, 0)) {
                                returndatacopy(ptr, 0, returndatasize())
                                revert(ptr, returndatasize())
                            }
                        }
                    }
            
                    return outputAmount;
                }
            }
            
            
            // File contracts/interfaces/IAggregationExecutor.sol
            
            
            pragma solidity 0.8.17;
            
            /// @title Interface for making arbitrary calls during swap
            interface IAggregationExecutor {
                /// @notice propagates information about original msg.sender and executes arbitrary data
                function execute(address msgSender) external payable;  // 0x4b64e492
            }
            
            
            // File @1inch/solidity-utils/contracts/interfaces/[email protected]
            
            
            pragma solidity ^0.8.0;
            
            
            interface IERC20MetadataUppercase {
                function NAME() external view returns (string memory);  // solhint-disable-line func-name-mixedcase
                function SYMBOL() external view returns (string memory);  // solhint-disable-line func-name-mixedcase
            }
            
            
            // File @1inch/solidity-utils/contracts/libraries/[email protected]
            
            
            pragma solidity ^0.8.0;
            
            /// @title Library with gas-efficient string operations
            library StringUtil {
                function toHex(uint256 value) internal pure returns (string memory) {
                    return toHex(abi.encodePacked(value));
                }
            
                function toHex(address value) internal pure returns (string memory) {
                    return toHex(abi.encodePacked(value));
                }
            
                function toHex(bytes memory data) internal pure returns (string memory result) {
                    /// @solidity memory-safe-assembly
                    assembly { // solhint-disable-line no-inline-assembly
                        function _toHex16(input) -> output {
                            output := or(
                                and(input, 0xFFFFFFFFFFFFFFFF000000000000000000000000000000000000000000000000),
                                shr(64, and(input, 0x0000000000000000FFFFFFFFFFFFFFFF00000000000000000000000000000000))
                            )
                            output := or(
                                and(output, 0xFFFFFFFF000000000000000000000000FFFFFFFF000000000000000000000000),
                                shr(32, and(output, 0x00000000FFFFFFFF000000000000000000000000FFFFFFFF0000000000000000))
                            )
                            output := or(
                                and(output, 0xFFFF000000000000FFFF000000000000FFFF000000000000FFFF000000000000),
                                shr(16, and(output, 0x0000FFFF000000000000FFFF000000000000FFFF000000000000FFFF00000000))
                            )
                            output := or(
                                and(output, 0xFF000000FF000000FF000000FF000000FF000000FF000000FF000000FF000000),
                                shr(8, and(output, 0x00FF000000FF000000FF000000FF000000FF000000FF000000FF000000FF0000))
                            )
                            output := or(
                                shr(4, and(output, 0xF000F000F000F000F000F000F000F000F000F000F000F000F000F000F000F000)),
                                shr(8, and(output, 0x0F000F000F000F000F000F000F000F000F000F000F000F000F000F000F000F00))
                            )
                            output := add(
                                add(0x3030303030303030303030303030303030303030303030303030303030303030, output),
                                mul(
                                    and(
                                        shr(4, add(output, 0x0606060606060606060606060606060606060606060606060606060606060606)),
                                        0x0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F0F
                                    ),
                                    7   // Change 7 to 39 for lower case output
                                )
                            )
                        }
            
                        result := mload(0x40)
                        let length := mload(data)
                        let resultLength := shl(1, length)
                        let toPtr := add(result, 0x22)          // 32 bytes for length + 2 bytes for '0x'
                        mstore(0x40, add(toPtr, resultLength))  // move free memory pointer
                        mstore(add(result, 2), 0x3078)          // 0x3078 is right aligned so we write to `result + 2`
                                                                // to store the last 2 bytes in the beginning of the string
                        mstore(result, add(resultLength, 2))    // extra 2 bytes for '0x'
            
                        for {
                            let fromPtr := add(data, 0x20)
                            let endPtr := add(fromPtr, length)
                        } lt(fromPtr, endPtr) {
                            fromPtr := add(fromPtr, 0x20)
                        } {
                            let rawData := mload(fromPtr)
                            let hexData := _toHex16(rawData)
                            mstore(toPtr, hexData)
                            toPtr := add(toPtr, 0x20)
                            hexData := _toHex16(shl(128, rawData))
                            mstore(toPtr, hexData)
                            toPtr := add(toPtr, 0x20)
                        }
                    }
                }
            }
            
            
            // File @openzeppelin/contracts/token/ERC20/extensions/[email protected]
            
            // OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/IERC20Metadata.sol)
            
            pragma solidity ^0.8.0;
            
            /**
             * @dev Interface for the optional metadata functions from the ERC20 standard.
             *
             * _Available since v4.1._
             */
            interface IERC20Metadata is IERC20 {
                /**
                 * @dev Returns the name of the token.
                 */
                function name() external view returns (string memory);
            
                /**
                 * @dev Returns the symbol of the token.
                 */
                function symbol() external view returns (string memory);
            
                /**
                 * @dev Returns the decimals places of the token.
                 */
                function decimals() external view returns (uint8);
            }
            
            
            // File @1inch/solidity-utils/contracts/libraries/[email protected]
            
            
            pragma solidity ^0.8.0;
            
            
            
            
            
            library UniERC20 {
                using SafeERC20 for IERC20;
            
                error InsufficientBalance();
                error ApproveCalledOnETH();
                error NotEnoughValue();
                error FromIsNotSender();
                error ToIsNotThis();
                error ETHTransferFailed();
            
                uint256 private constant _RAW_CALL_GAS_LIMIT = 5000;
                IERC20 private constant _ETH_ADDRESS = IERC20(0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE);
                IERC20 private constant _ZERO_ADDRESS = IERC20(address(0));
            
                function isETH(IERC20 token) internal pure returns (bool) {
                    return (token == _ZERO_ADDRESS || token == _ETH_ADDRESS);
                }
            
                function uniBalanceOf(IERC20 token, address account) internal view returns (uint256) {
                    if (isETH(token)) {
                        return account.balance;
                    } else {
                        return token.balanceOf(account);
                    }
                }
            
                /// @dev note that this function does nothing in case of zero amount
                function uniTransfer(IERC20 token, address payable to, uint256 amount) internal {
                    if (amount > 0) {
                        if (isETH(token)) {
                            if (address(this).balance < amount) revert InsufficientBalance();
                            // solhint-disable-next-line avoid-low-level-calls
                            (bool success, ) = to.call{value: amount, gas: _RAW_CALL_GAS_LIMIT}("");
                            if (!success) revert ETHTransferFailed();
                        } else {
                            token.safeTransfer(to, amount);
                        }
                    }
                }
            
                /// @dev note that this function does nothing in case of zero amount
                function uniTransferFrom(IERC20 token, address payable from, address to, uint256 amount) internal {
                    if (amount > 0) {
                        if (isETH(token)) {
                            if (msg.value < amount) revert NotEnoughValue();
                            if (from != msg.sender) revert FromIsNotSender();
                            if (to != address(this)) revert ToIsNotThis();
                            if (msg.value > amount) {
                                // Return remainder if exist
                                unchecked {
                                    // solhint-disable-next-line avoid-low-level-calls
                                    (bool success, ) = from.call{value: msg.value - amount, gas: _RAW_CALL_GAS_LIMIT}("");
                                    if (!success) revert ETHTransferFailed();
                                }
                            }
                        } else {
                            token.safeTransferFrom(from, to, amount);
                        }
                    }
                }
            
                function uniSymbol(IERC20 token) internal view returns(string memory) {
                    return _uniDecode(token, IERC20Metadata.symbol.selector, IERC20MetadataUppercase.SYMBOL.selector);
                }
            
                function uniName(IERC20 token) internal view returns(string memory) {
                    return _uniDecode(token, IERC20Metadata.name.selector, IERC20MetadataUppercase.NAME.selector);
                }
            
                function uniApprove(IERC20 token, address to, uint256 amount) internal {
                    if (isETH(token)) revert ApproveCalledOnETH();
            
                    token.forceApprove(to, amount);
                }
            
                /// 20K gas is provided to account for possible implementations of name/symbol
                /// (token implementation might be behind proxy or store the value in storage)
                function _uniDecode(IERC20 token, bytes4 lowerCaseSelector, bytes4 upperCaseSelector) private view returns(string memory result) {
                    if (isETH(token)) {
                        return "ETH";
                    }
            
                    (bool success, bytes memory data) = address(token).staticcall{ gas: 20000 }(
                        abi.encodeWithSelector(lowerCaseSelector)
                    );
                    if (!success) {
                        (success, data) = address(token).staticcall{ gas: 20000 }(
                            abi.encodeWithSelector(upperCaseSelector)
                        );
                    }
            
                    if (success && data.length >= 0x40) {
                        (uint256 offset, uint256 len) = abi.decode(data, (uint256, uint256));
                        if (offset == 0x20 && len > 0 && data.length == 0x40 + len) {
                            /// @solidity memory-safe-assembly
                            assembly { // solhint-disable-line no-inline-assembly
                                result := add(data, 0x20)
                            }
                            return result;
                        }
                    }
            
                    if (success && data.length == 32) {
                        uint256 len = 0;
                        while (len < data.length && data[len] >= 0x20 && data[len] <= 0x7E) {
                            unchecked {
                                len++;
                            }
                        }
            
                        if (len > 0) {
                            /// @solidity memory-safe-assembly
                            assembly { // solhint-disable-line no-inline-assembly
                                mstore(data, len)
                            }
                            return string(data);
                        }
                    }
            
                    return StringUtil.toHex(address(token));
                }
            }
            
            
            // File contracts/routers/GenericRouter.sol
            
            
            pragma solidity 0.8.17;
            
            
            
            
            
            contract GenericRouter is EthReceiver {
                using UniERC20 for IERC20;
                using SafeERC20 for IERC20;
            
                error ZeroMinReturn();
                error ZeroReturnAmount();
            
                uint256 private constant _PARTIAL_FILL = 1 << 0;
                uint256 private constant _REQUIRES_EXTRA_ETH = 1 << 1;
            
                struct SwapDescription {
                    IERC20 srcToken;
                    IERC20 dstToken;
                    address payable srcReceiver;
                    address payable dstReceiver;
                    uint256 amount;
                    uint256 minReturnAmount;
                    uint256 flags;
                }
            
                /// @notice Performs a swap, delegating all calls encoded in `data` to `executor`. See tests for usage examples
                /// @dev router keeps 1 wei of every token on the contract balance for gas optimisations reasons. This affects first swap of every token by leaving 1 wei on the contract.
                /// @param executor Aggregation executor that executes calls described in `data`
                /// @param desc Swap description
                /// @param permit Should contain valid permit that can be used in `IERC20Permit.permit` calls.
                /// @param data Encoded calls that `caller` should execute in between of swaps
                /// @return returnAmount Resulting token amount
                /// @return spentAmount Source token amount
                function swap(
                    IAggregationExecutor executor,
                    SwapDescription calldata desc,
                    bytes calldata permit,
                    bytes calldata data
                )
                    external
                    payable
                    returns (
                        uint256 returnAmount,
                        uint256 spentAmount
                    )
                {
                    if (desc.minReturnAmount == 0) revert ZeroMinReturn();
            
                    IERC20 srcToken = desc.srcToken;
                    IERC20 dstToken = desc.dstToken;
            
                    bool srcETH = srcToken.isETH();
                    if (desc.flags & _REQUIRES_EXTRA_ETH != 0) {
                        if (msg.value <= (srcETH ? desc.amount : 0)) revert RouterErrors.InvalidMsgValue();
                    } else {
                        if (msg.value != (srcETH ? desc.amount : 0)) revert RouterErrors.InvalidMsgValue();
                    }
            
                    if (!srcETH) {
                        if (permit.length > 0) {
                            srcToken.safePermit(permit);
                        }
                        srcToken.safeTransferFrom(msg.sender, desc.srcReceiver, desc.amount);
                    }
            
                    _execute(executor, msg.sender, desc.amount, data);
            
                    spentAmount = desc.amount;
                    // we leave 1 wei on the router for gas optimisations reasons
                    returnAmount = dstToken.uniBalanceOf(address(this));
                    if (returnAmount == 0) revert ZeroReturnAmount();
                    unchecked { returnAmount--; }
            
                    if (desc.flags & _PARTIAL_FILL != 0) {
                        uint256 unspentAmount = srcToken.uniBalanceOf(address(this));
                        if (unspentAmount > 1) {
                            // we leave 1 wei on the router for gas optimisations reasons
                            unchecked { unspentAmount--; }
                            spentAmount -= unspentAmount;
                            srcToken.uniTransfer(payable(msg.sender), unspentAmount);
                        }
                        if (returnAmount * desc.amount < desc.minReturnAmount * spentAmount) revert RouterErrors.ReturnAmountIsNotEnough();
                    } else {
                        if (returnAmount < desc.minReturnAmount) revert RouterErrors.ReturnAmountIsNotEnough();
                    }
            
                    address payable dstReceiver = (desc.dstReceiver == address(0)) ? payable(msg.sender) : desc.dstReceiver;
                    dstToken.uniTransfer(dstReceiver, returnAmount);
                }
            
                function _execute(
                    IAggregationExecutor executor,
                    address srcTokenOwner,
                    uint256 inputAmount,
                    bytes calldata data
                ) private {
                    bytes4 executeSelector = executor.execute.selector;
                    /// @solidity memory-safe-assembly
                    assembly {  // solhint-disable-line no-inline-assembly
                        let ptr := mload(0x40)
            
                        mstore(ptr, executeSelector)
                        mstore(add(ptr, 0x04), srcTokenOwner)
                        calldatacopy(add(ptr, 0x24), data.offset, data.length)
                        mstore(add(add(ptr, 0x24), data.length), inputAmount)
            
                        if iszero(call(gas(), executor, callvalue(), ptr, add(0x44, data.length), 0, 0)) {
                            returndatacopy(ptr, 0, returndatasize())
                            revert(ptr, returndatasize())
                        }
                    }
                }
            }
            
            
            // File contracts/routers/UnoswapRouter.sol
            
            
            pragma solidity 0.8.17;
            
            
            
            
            contract UnoswapRouter is EthReceiver {
                using SafeERC20 for IERC20;
            
                error ReservesCallFailed();
                error SwapAmountTooLarge();
            
                bytes4 private constant _TRANSFER_FROM_CALL_SELECTOR = 0x23b872dd;
                bytes4 private constant _WETH_DEPOSIT_CALL_SELECTOR = 0xd0e30db0;
                bytes4 private constant _WETH_WITHDRAW_CALL_SELECTOR = 0x2e1a7d4d;
                bytes4 private constant _ERC20_TRANSFER_CALL_SELECTOR = 0xa9059cbb;
                uint256 private constant _ADDRESS_MASK =   0x000000000000000000000000ffffffffffffffffffffffffffffffffffffffff;
                uint256 private constant _REVERSE_MASK =   0x8000000000000000000000000000000000000000000000000000000000000000;
                uint256 private constant _WETH_MASK =      0x4000000000000000000000000000000000000000000000000000000000000000;
                uint256 private constant _NUMERATOR_MASK = 0x0000000000000000ffffffff0000000000000000000000000000000000000000;
                /// @dev WETH address is network-specific and needs to be changed before deployment.
                /// It can not be moved to immutable as immutables are not supported in assembly
                address private constant _WETH = 0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2;
                bytes4 private constant _UNISWAP_PAIR_RESERVES_CALL_SELECTOR = 0x0902f1ac;
                bytes4 private constant _UNISWAP_PAIR_SWAP_CALL_SELECTOR = 0x022c0d9f;
                uint256 private constant _DENOMINATOR = 1e9;
                uint256 private constant _NUMERATOR_OFFSET = 160;
                uint256 private constant _MAX_SWAP_AMOUNT = (1 << 112) - 1;  // type(uint112).max;
            
                /// @notice Same as `unoswapTo` but calls permit first,
                /// allowing to approve token spending and make a swap in one transaction.
                /// @param recipient Address that will receive swapped funds
                /// @param srcToken Source token
                /// @param amount Amount of source tokens to swap
                /// @param minReturn Minimal allowed returnAmount to make transaction commit
                /// @param pools Pools chain used for swaps. Pools src and dst tokens should match to make swap happen
                /// @param permit Should contain valid permit that can be used in `IERC20Permit.permit` calls.
                /// See tests for examples
                function unoswapToWithPermit(
                    address payable recipient,
                    IERC20 srcToken,
                    uint256 amount,
                    uint256 minReturn,
                    uint256[] calldata pools,
                    bytes calldata permit
                ) external returns(uint256 returnAmount) {
                    srcToken.safePermit(permit);
                    return _unoswap(recipient, srcToken, amount, minReturn, pools);
                }
            
                /// @notice Performs swap using Uniswap exchange. Wraps and unwraps ETH if required.
                /// Sending non-zero `msg.value` for anything but ETH swaps is prohibited
                /// @param recipient Address that will receive swapped funds
                /// @param srcToken Source token
                /// @param amount Amount of source tokens to swap
                /// @param minReturn Minimal allowed returnAmount to make transaction commit
                /// @param pools Pools chain used for swaps. Pools src and dst tokens should match to make swap happen
                function unoswapTo(
                    address payable recipient,
                    IERC20 srcToken,
                    uint256 amount,
                    uint256 minReturn,
                    uint256[] calldata pools
                ) external payable returns(uint256 returnAmount) {
                    return _unoswap(recipient, srcToken, amount, minReturn, pools);
                }
            
                /// @notice Performs swap using Uniswap exchange. Wraps and unwraps ETH if required.
                /// Sending non-zero `msg.value` for anything but ETH swaps is prohibited
                /// @param srcToken Source token
                /// @param amount Amount of source tokens to swap
                /// @param minReturn Minimal allowed returnAmount to make transaction commit
                /// @param pools Pools chain used for swaps. Pools src and dst tokens should match to make swap happen
                function unoswap(
                    IERC20 srcToken,
                    uint256 amount,
                    uint256 minReturn,
                    uint256[] calldata pools
                ) external payable returns(uint256 returnAmount) {
                    return _unoswap(payable(msg.sender), srcToken, amount, minReturn, pools);
                }
            
                function _unoswap(
                    address payable recipient,
                    IERC20 srcToken,
                    uint256 amount,
                    uint256 minReturn,
                    uint256[] calldata pools
                ) private returns(uint256 returnAmount) {
                    assembly {  // solhint-disable-line no-inline-assembly
                        function reRevert() {
                            returndatacopy(0, 0, returndatasize())
                            revert(0, returndatasize())
                        }
            
                        function validateERC20Transfer(status) {
                            if iszero(status) {
                                reRevert()
                            }
                            let success := or(
                                iszero(returndatasize()),                       // empty return data
                                and(gt(returndatasize(), 31), eq(mload(0), 1))  // true in return data
                            )
                            if iszero(success) {
                                mstore(0, 0xf27f64e400000000000000000000000000000000000000000000000000000000)  // ERC20TransferFailed()
                                revert(0, 4)
                            }
                        }
            
                        function swap(emptyPtr, swapAmount, pair, reversed, numerator, to) -> ret {
                            mstore(emptyPtr, _UNISWAP_PAIR_RESERVES_CALL_SELECTOR)
                            if iszero(staticcall(gas(), pair, emptyPtr, 0x4, emptyPtr, 0x40)) {
                                reRevert()
                            }
                            if iszero(eq(returndatasize(), 0x60)) {
                                mstore(0, 0x85cd58dc00000000000000000000000000000000000000000000000000000000)  // ReservesCallFailed()
                                revert(0, 4)
                            }
            
                            let reserve0 := mload(emptyPtr)
                            let reserve1 := mload(add(emptyPtr, 0x20))
                            if reversed {
                                let tmp := reserve0
                                reserve0 := reserve1
                                reserve1 := tmp
                            }
                            // this will not overflow as reserve0, reserve1 and ret fit to 112 bit and numerator and _DENOMINATOR fit to 32 bit
                            ret := mul(swapAmount, numerator)
                            ret := div(mul(ret, reserve1), add(ret, mul(reserve0, _DENOMINATOR)))
            
                            mstore(emptyPtr, _UNISWAP_PAIR_SWAP_CALL_SELECTOR)
                            reversed := iszero(reversed)
                            mstore(add(emptyPtr, 0x04), mul(ret, iszero(reversed)))
                            mstore(add(emptyPtr, 0x24), mul(ret, reversed))
                            mstore(add(emptyPtr, 0x44), to)
                            mstore(add(emptyPtr, 0x64), 0x80)
                            mstore(add(emptyPtr, 0x84), 0)
                            if iszero(call(gas(), pair, 0, emptyPtr, 0xa4, 0, 0)) {
                                reRevert()
                            }
                        }
            
                        // make sure that input amount fits in 112 bit
                        if gt(amount, _MAX_SWAP_AMOUNT) {
                            mstore(0, 0xcf0b4d3a00000000000000000000000000000000000000000000000000000000)  // SwapAmountTooLarge()
                            revert(0, 4)
                        }
            
                        let emptyPtr := mload(0x40)
                        mstore(0x40, add(emptyPtr, 0xc0))
            
                        let poolsEndOffset := add(pools.offset, shl(5, pools.length))
                        let rawPair := calldataload(pools.offset)
                        switch srcToken
                        case 0 {
                            if iszero(eq(amount, callvalue())) {
                                mstore(0, 0x1841b4e100000000000000000000000000000000000000000000000000000000)  // InvalidMsgValue()
                                revert(0, 4)
                            }
            
                            mstore(emptyPtr, _WETH_DEPOSIT_CALL_SELECTOR)
                            if iszero(call(gas(), _WETH, amount, emptyPtr, 0x4, 0, 0)) {
                                reRevert()
                            }
            
                            mstore(emptyPtr, _ERC20_TRANSFER_CALL_SELECTOR)
                            mstore(add(emptyPtr, 0x4), and(rawPair, _ADDRESS_MASK))
                            mstore(add(emptyPtr, 0x24), amount)
                            if iszero(call(gas(), _WETH, 0, emptyPtr, 0x44, 0, 0)) {
                                reRevert()
                            }
                        }
                        default {
                            if callvalue() {
                                mstore(0, 0x1841b4e100000000000000000000000000000000000000000000000000000000)  // InvalidMsgValue()
                                revert(0, 4)
                            }
            
                            mstore(emptyPtr, _TRANSFER_FROM_CALL_SELECTOR)
                            mstore(add(emptyPtr, 0x4), caller())
                            mstore(add(emptyPtr, 0x24), and(rawPair, _ADDRESS_MASK))
                            mstore(add(emptyPtr, 0x44), amount)
                            validateERC20Transfer(
                                call(gas(), srcToken, 0, emptyPtr, 0x64, 0, 0x20)
                            )
                        }
            
                        returnAmount := amount
            
                        for {let i := add(pools.offset, 0x20)} lt(i, poolsEndOffset) {i := add(i, 0x20)} {
                            let nextRawPair := calldataload(i)
            
                            returnAmount := swap(
                                emptyPtr,
                                returnAmount,
                                and(rawPair, _ADDRESS_MASK),
                                and(rawPair, _REVERSE_MASK),
                                shr(_NUMERATOR_OFFSET, and(rawPair, _NUMERATOR_MASK)),
                                and(nextRawPair, _ADDRESS_MASK)
                            )
            
                            rawPair := nextRawPair
                        }
            
                        switch and(rawPair, _WETH_MASK)
                        case 0 {
                            returnAmount := swap(
                                emptyPtr,
                                returnAmount,
                                and(rawPair, _ADDRESS_MASK),
                                and(rawPair, _REVERSE_MASK),
                                shr(_NUMERATOR_OFFSET, and(rawPair, _NUMERATOR_MASK)),
                                recipient
                            )
                        }
                        default {
                            returnAmount := swap(
                                emptyPtr,
                                returnAmount,
                                and(rawPair, _ADDRESS_MASK),
                                and(rawPair, _REVERSE_MASK),
                                shr(_NUMERATOR_OFFSET, and(rawPair, _NUMERATOR_MASK)),
                                address()
                            )
            
                            mstore(emptyPtr, _WETH_WITHDRAW_CALL_SELECTOR)
                            mstore(add(emptyPtr, 0x04), returnAmount)
                            if iszero(call(gas(), _WETH, 0, emptyPtr, 0x24, 0, 0)) {
                                reRevert()
                            }
            
                            if iszero(call(gas(), recipient, returnAmount, 0, 0, 0, 0)) {
                                reRevert()
                            }
                        }
                    }
                    if (returnAmount < minReturn) revert RouterErrors.ReturnAmountIsNotEnough();
                }
            }
            
            
            // File contracts/interfaces/IUniswapV3Pool.sol
            
            pragma solidity 0.8.17;
            
            interface IUniswapV3Pool {
                /// @notice Swap token0 for token1, or token1 for token0
                /// @dev The caller of this method receives a callback in the form of IUniswapV3SwapCallback#uniswapV3SwapCallback
                /// @param recipient The address to receive the output of the swap
                /// @param zeroForOne The direction of the swap, true for token0 to token1, false for token1 to token0
                /// @param amountSpecified The amount of the swap, which implicitly configures the swap as exact input (positive), or exact output (negative)
                /// @param sqrtPriceLimitX96 The Q64.96 sqrt price limit. If zero for one, the price cannot be less than this
                /// value after the swap. If one for zero, the price cannot be greater than this value after the swap
                /// @param data Any data to be passed through to the callback
                /// @return amount0 The delta of the balance of token0 of the pool, exact when negative, minimum when positive
                /// @return amount1 The delta of the balance of token1 of the pool, exact when negative, minimum when positive
                function swap(
                    address recipient,
                    bool zeroForOne,
                    int256 amountSpecified,
                    uint160 sqrtPriceLimitX96,
                    bytes calldata data
                ) external returns (int256 amount0, int256 amount1);
            
                /// @notice The first of the two tokens of the pool, sorted by address
                /// @return The token contract address
                function token0() external view returns (address);
            
                /// @notice The second of the two tokens of the pool, sorted by address
                /// @return The token contract address
                function token1() external view returns (address);
            
                /// @notice The pool's fee in hundredths of a bip, i.e. 1e-6
                /// @return The fee
                function fee() external view returns (uint24);
            }
            
            
            // File contracts/interfaces/IUniswapV3SwapCallback.sol
            
            pragma solidity 0.8.17;
            
            /// @title Callback for IUniswapV3PoolActions#swap
            /// @notice Any contract that calls IUniswapV3PoolActions#swap must implement this interface
            interface IUniswapV3SwapCallback {
                /// @notice Called to `msg.sender` after executing a swap via IUniswapV3Pool#swap.
                /// @dev In the implementation you must pay the pool tokens owed for the swap.
                /// The caller of this method must be checked to be a UniswapV3Pool deployed by the canonical UniswapV3Factory.
                /// amount0Delta and amount1Delta can both be 0 if no tokens were swapped.
                /// @param amount0Delta The amount of token0 that was sent (negative) or must be received (positive) by the pool by
                /// the end of the swap. If positive, the callback must send that amount of token0 to the pool.
                /// @param amount1Delta The amount of token1 that was sent (negative) or must be received (positive) by the pool by
                /// the end of the swap. If positive, the callback must send that amount of token1 to the pool.
                /// @param data Any data passed through by the caller via the IUniswapV3PoolActions#swap call
                function uniswapV3SwapCallback(
                    int256 amount0Delta,
                    int256 amount1Delta,
                    bytes calldata data
                ) external;
            }
            
            
            // File @openzeppelin/contracts/utils/[email protected]
            
            // OpenZeppelin Contracts (last updated v4.7.0) (utils/Address.sol)
            
            pragma solidity ^0.8.1;
            
            /**
             * @dev Collection of functions related to the address type
             */
            library Address {
                /**
                 * @dev Returns true if `account` is a contract.
                 *
                 * [IMPORTANT]
                 * ====
                 * It is unsafe to assume that an address for which this function returns
                 * false is an externally-owned account (EOA) and not a contract.
                 *
                 * Among others, `isContract` will return false for the following
                 * types of addresses:
                 *
                 *  - an externally-owned account
                 *  - a contract in construction
                 *  - an address where a contract will be created
                 *  - an address where a contract lived, but was destroyed
                 * ====
                 *
                 * [IMPORTANT]
                 * ====
                 * You shouldn't rely on `isContract` to protect against flash loan attacks!
                 *
                 * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
                 * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
                 * constructor.
                 * ====
                 */
                function isContract(address account) internal view returns (bool) {
                    // This method relies on extcodesize/address.code.length, which returns 0
                    // for contracts in construction, since the code is only stored at the end
                    // of the constructor execution.
            
                    return account.code.length > 0;
                }
            
                /**
                 * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
                 * `recipient`, forwarding all available gas and reverting on errors.
                 *
                 * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
                 * of certain opcodes, possibly making contracts go over the 2300 gas limit
                 * imposed by `transfer`, making them unable to receive funds via
                 * `transfer`. {sendValue} removes this limitation.
                 *
                 * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
                 *
                 * IMPORTANT: because control is transferred to `recipient`, care must be
                 * taken to not create reentrancy vulnerabilities. Consider using
                 * {ReentrancyGuard} or the
                 * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
                 */
                function sendValue(address payable recipient, uint256 amount) internal {
                    require(address(this).balance >= amount, "Address: insufficient balance");
            
                    (bool success, ) = recipient.call{value: amount}("");
                    require(success, "Address: unable to send value, recipient may have reverted");
                }
            
                /**
                 * @dev Performs a Solidity function call using a low level `call`. A
                 * plain `call` is an unsafe replacement for a function call: use this
                 * function instead.
                 *
                 * If `target` reverts with a revert reason, it is bubbled up by this
                 * function (like regular Solidity function calls).
                 *
                 * Returns the raw returned data. To convert to the expected return value,
                 * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
                 *
                 * Requirements:
                 *
                 * - `target` must be a contract.
                 * - calling `target` with `data` must not revert.
                 *
                 * _Available since v3.1._
                 */
                function functionCall(address target, bytes memory data) internal returns (bytes memory) {
                    return functionCall(target, data, "Address: low-level call failed");
                }
            
                /**
                 * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
                 * `errorMessage` as a fallback revert reason when `target` reverts.
                 *
                 * _Available since v3.1._
                 */
                function functionCall(
                    address target,
                    bytes memory data,
                    string memory errorMessage
                ) internal returns (bytes memory) {
                    return functionCallWithValue(target, data, 0, errorMessage);
                }
            
                /**
                 * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                 * but also transferring `value` wei to `target`.
                 *
                 * Requirements:
                 *
                 * - the calling contract must have an ETH balance of at least `value`.
                 * - the called Solidity function must be `payable`.
                 *
                 * _Available since v3.1._
                 */
                function functionCallWithValue(
                    address target,
                    bytes memory data,
                    uint256 value
                ) internal returns (bytes memory) {
                    return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
                }
            
                /**
                 * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
                 * with `errorMessage` as a fallback revert reason when `target` reverts.
                 *
                 * _Available since v3.1._
                 */
                function functionCallWithValue(
                    address target,
                    bytes memory data,
                    uint256 value,
                    string memory errorMessage
                ) internal returns (bytes memory) {
                    require(address(this).balance >= value, "Address: insufficient balance for call");
                    require(isContract(target), "Address: call to non-contract");
            
                    (bool success, bytes memory returndata) = target.call{value: value}(data);
                    return verifyCallResult(success, returndata, errorMessage);
                }
            
                /**
                 * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                 * but performing a static call.
                 *
                 * _Available since v3.3._
                 */
                function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
                    return functionStaticCall(target, data, "Address: low-level static call failed");
                }
            
                /**
                 * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
                 * but performing a static call.
                 *
                 * _Available since v3.3._
                 */
                function functionStaticCall(
                    address target,
                    bytes memory data,
                    string memory errorMessage
                ) internal view returns (bytes memory) {
                    require(isContract(target), "Address: static call to non-contract");
            
                    (bool success, bytes memory returndata) = target.staticcall(data);
                    return verifyCallResult(success, returndata, errorMessage);
                }
            
                /**
                 * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
                 * but performing a delegate call.
                 *
                 * _Available since v3.4._
                 */
                function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
                    return functionDelegateCall(target, data, "Address: low-level delegate call failed");
                }
            
                /**
                 * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
                 * but performing a delegate call.
                 *
                 * _Available since v3.4._
                 */
                function functionDelegateCall(
                    address target,
                    bytes memory data,
                    string memory errorMessage
                ) internal returns (bytes memory) {
                    require(isContract(target), "Address: delegate call to non-contract");
            
                    (bool success, bytes memory returndata) = target.delegatecall(data);
                    return verifyCallResult(success, returndata, errorMessage);
                }
            
                /**
                 * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
                 * revert reason using the provided one.
                 *
                 * _Available since v4.3._
                 */
                function verifyCallResult(
                    bool success,
                    bytes memory returndata,
                    string memory errorMessage
                ) internal pure returns (bytes memory) {
                    if (success) {
                        return returndata;
                    } else {
                        // Look for revert reason and bubble it up if present
                        if (returndata.length > 0) {
                            // The easiest way to bubble the revert reason is using memory via assembly
                            /// @solidity memory-safe-assembly
                            assembly {
                                let returndata_size := mload(returndata)
                                revert(add(32, returndata), returndata_size)
                            }
                        } else {
                            revert(errorMessage);
                        }
                    }
                }
            }
            
            
            // File @openzeppelin/contracts/utils/math/[email protected]
            
            // OpenZeppelin Contracts (last updated v4.7.0) (utils/math/SafeCast.sol)
            
            pragma solidity ^0.8.0;
            
            /**
             * @dev Wrappers over Solidity's uintXX/intXX casting operators with added overflow
             * checks.
             *
             * Downcasting from uint256/int256 in Solidity does not revert on overflow. This can
             * easily result in undesired exploitation or bugs, since developers usually
             * assume that overflows raise errors. `SafeCast` restores this intuition by
             * reverting the transaction when such an operation overflows.
             *
             * Using this library instead of the unchecked operations eliminates an entire
             * class of bugs, so it's recommended to use it always.
             *
             * Can be combined with {SafeMath} and {SignedSafeMath} to extend it to smaller types, by performing
             * all math on `uint256` and `int256` and then downcasting.
             */
            library SafeCast {
                /**
                 * @dev Returns the downcasted uint248 from uint256, reverting on
                 * overflow (when the input is greater than largest uint248).
                 *
                 * Counterpart to Solidity's `uint248` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 248 bits
                 *
                 * _Available since v4.7._
                 */
                function toUint248(uint256 value) internal pure returns (uint248) {
                    require(value <= type(uint248).max, "SafeCast: value doesn't fit in 248 bits");
                    return uint248(value);
                }
            
                /**
                 * @dev Returns the downcasted uint240 from uint256, reverting on
                 * overflow (when the input is greater than largest uint240).
                 *
                 * Counterpart to Solidity's `uint240` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 240 bits
                 *
                 * _Available since v4.7._
                 */
                function toUint240(uint256 value) internal pure returns (uint240) {
                    require(value <= type(uint240).max, "SafeCast: value doesn't fit in 240 bits");
                    return uint240(value);
                }
            
                /**
                 * @dev Returns the downcasted uint232 from uint256, reverting on
                 * overflow (when the input is greater than largest uint232).
                 *
                 * Counterpart to Solidity's `uint232` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 232 bits
                 *
                 * _Available since v4.7._
                 */
                function toUint232(uint256 value) internal pure returns (uint232) {
                    require(value <= type(uint232).max, "SafeCast: value doesn't fit in 232 bits");
                    return uint232(value);
                }
            
                /**
                 * @dev Returns the downcasted uint224 from uint256, reverting on
                 * overflow (when the input is greater than largest uint224).
                 *
                 * Counterpart to Solidity's `uint224` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 224 bits
                 *
                 * _Available since v4.2._
                 */
                function toUint224(uint256 value) internal pure returns (uint224) {
                    require(value <= type(uint224).max, "SafeCast: value doesn't fit in 224 bits");
                    return uint224(value);
                }
            
                /**
                 * @dev Returns the downcasted uint216 from uint256, reverting on
                 * overflow (when the input is greater than largest uint216).
                 *
                 * Counterpart to Solidity's `uint216` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 216 bits
                 *
                 * _Available since v4.7._
                 */
                function toUint216(uint256 value) internal pure returns (uint216) {
                    require(value <= type(uint216).max, "SafeCast: value doesn't fit in 216 bits");
                    return uint216(value);
                }
            
                /**
                 * @dev Returns the downcasted uint208 from uint256, reverting on
                 * overflow (when the input is greater than largest uint208).
                 *
                 * Counterpart to Solidity's `uint208` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 208 bits
                 *
                 * _Available since v4.7._
                 */
                function toUint208(uint256 value) internal pure returns (uint208) {
                    require(value <= type(uint208).max, "SafeCast: value doesn't fit in 208 bits");
                    return uint208(value);
                }
            
                /**
                 * @dev Returns the downcasted uint200 from uint256, reverting on
                 * overflow (when the input is greater than largest uint200).
                 *
                 * Counterpart to Solidity's `uint200` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 200 bits
                 *
                 * _Available since v4.7._
                 */
                function toUint200(uint256 value) internal pure returns (uint200) {
                    require(value <= type(uint200).max, "SafeCast: value doesn't fit in 200 bits");
                    return uint200(value);
                }
            
                /**
                 * @dev Returns the downcasted uint192 from uint256, reverting on
                 * overflow (when the input is greater than largest uint192).
                 *
                 * Counterpart to Solidity's `uint192` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 192 bits
                 *
                 * _Available since v4.7._
                 */
                function toUint192(uint256 value) internal pure returns (uint192) {
                    require(value <= type(uint192).max, "SafeCast: value doesn't fit in 192 bits");
                    return uint192(value);
                }
            
                /**
                 * @dev Returns the downcasted uint184 from uint256, reverting on
                 * overflow (when the input is greater than largest uint184).
                 *
                 * Counterpart to Solidity's `uint184` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 184 bits
                 *
                 * _Available since v4.7._
                 */
                function toUint184(uint256 value) internal pure returns (uint184) {
                    require(value <= type(uint184).max, "SafeCast: value doesn't fit in 184 bits");
                    return uint184(value);
                }
            
                /**
                 * @dev Returns the downcasted uint176 from uint256, reverting on
                 * overflow (when the input is greater than largest uint176).
                 *
                 * Counterpart to Solidity's `uint176` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 176 bits
                 *
                 * _Available since v4.7._
                 */
                function toUint176(uint256 value) internal pure returns (uint176) {
                    require(value <= type(uint176).max, "SafeCast: value doesn't fit in 176 bits");
                    return uint176(value);
                }
            
                /**
                 * @dev Returns the downcasted uint168 from uint256, reverting on
                 * overflow (when the input is greater than largest uint168).
                 *
                 * Counterpart to Solidity's `uint168` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 168 bits
                 *
                 * _Available since v4.7._
                 */
                function toUint168(uint256 value) internal pure returns (uint168) {
                    require(value <= type(uint168).max, "SafeCast: value doesn't fit in 168 bits");
                    return uint168(value);
                }
            
                /**
                 * @dev Returns the downcasted uint160 from uint256, reverting on
                 * overflow (when the input is greater than largest uint160).
                 *
                 * Counterpart to Solidity's `uint160` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 160 bits
                 *
                 * _Available since v4.7._
                 */
                function toUint160(uint256 value) internal pure returns (uint160) {
                    require(value <= type(uint160).max, "SafeCast: value doesn't fit in 160 bits");
                    return uint160(value);
                }
            
                /**
                 * @dev Returns the downcasted uint152 from uint256, reverting on
                 * overflow (when the input is greater than largest uint152).
                 *
                 * Counterpart to Solidity's `uint152` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 152 bits
                 *
                 * _Available since v4.7._
                 */
                function toUint152(uint256 value) internal pure returns (uint152) {
                    require(value <= type(uint152).max, "SafeCast: value doesn't fit in 152 bits");
                    return uint152(value);
                }
            
                /**
                 * @dev Returns the downcasted uint144 from uint256, reverting on
                 * overflow (when the input is greater than largest uint144).
                 *
                 * Counterpart to Solidity's `uint144` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 144 bits
                 *
                 * _Available since v4.7._
                 */
                function toUint144(uint256 value) internal pure returns (uint144) {
                    require(value <= type(uint144).max, "SafeCast: value doesn't fit in 144 bits");
                    return uint144(value);
                }
            
                /**
                 * @dev Returns the downcasted uint136 from uint256, reverting on
                 * overflow (when the input is greater than largest uint136).
                 *
                 * Counterpart to Solidity's `uint136` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 136 bits
                 *
                 * _Available since v4.7._
                 */
                function toUint136(uint256 value) internal pure returns (uint136) {
                    require(value <= type(uint136).max, "SafeCast: value doesn't fit in 136 bits");
                    return uint136(value);
                }
            
                /**
                 * @dev Returns the downcasted uint128 from uint256, reverting on
                 * overflow (when the input is greater than largest uint128).
                 *
                 * Counterpart to Solidity's `uint128` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 128 bits
                 *
                 * _Available since v2.5._
                 */
                function toUint128(uint256 value) internal pure returns (uint128) {
                    require(value <= type(uint128).max, "SafeCast: value doesn't fit in 128 bits");
                    return uint128(value);
                }
            
                /**
                 * @dev Returns the downcasted uint120 from uint256, reverting on
                 * overflow (when the input is greater than largest uint120).
                 *
                 * Counterpart to Solidity's `uint120` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 120 bits
                 *
                 * _Available since v4.7._
                 */
                function toUint120(uint256 value) internal pure returns (uint120) {
                    require(value <= type(uint120).max, "SafeCast: value doesn't fit in 120 bits");
                    return uint120(value);
                }
            
                /**
                 * @dev Returns the downcasted uint112 from uint256, reverting on
                 * overflow (when the input is greater than largest uint112).
                 *
                 * Counterpart to Solidity's `uint112` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 112 bits
                 *
                 * _Available since v4.7._
                 */
                function toUint112(uint256 value) internal pure returns (uint112) {
                    require(value <= type(uint112).max, "SafeCast: value doesn't fit in 112 bits");
                    return uint112(value);
                }
            
                /**
                 * @dev Returns the downcasted uint104 from uint256, reverting on
                 * overflow (when the input is greater than largest uint104).
                 *
                 * Counterpart to Solidity's `uint104` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 104 bits
                 *
                 * _Available since v4.7._
                 */
                function toUint104(uint256 value) internal pure returns (uint104) {
                    require(value <= type(uint104).max, "SafeCast: value doesn't fit in 104 bits");
                    return uint104(value);
                }
            
                /**
                 * @dev Returns the downcasted uint96 from uint256, reverting on
                 * overflow (when the input is greater than largest uint96).
                 *
                 * Counterpart to Solidity's `uint96` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 96 bits
                 *
                 * _Available since v4.2._
                 */
                function toUint96(uint256 value) internal pure returns (uint96) {
                    require(value <= type(uint96).max, "SafeCast: value doesn't fit in 96 bits");
                    return uint96(value);
                }
            
                /**
                 * @dev Returns the downcasted uint88 from uint256, reverting on
                 * overflow (when the input is greater than largest uint88).
                 *
                 * Counterpart to Solidity's `uint88` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 88 bits
                 *
                 * _Available since v4.7._
                 */
                function toUint88(uint256 value) internal pure returns (uint88) {
                    require(value <= type(uint88).max, "SafeCast: value doesn't fit in 88 bits");
                    return uint88(value);
                }
            
                /**
                 * @dev Returns the downcasted uint80 from uint256, reverting on
                 * overflow (when the input is greater than largest uint80).
                 *
                 * Counterpart to Solidity's `uint80` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 80 bits
                 *
                 * _Available since v4.7._
                 */
                function toUint80(uint256 value) internal pure returns (uint80) {
                    require(value <= type(uint80).max, "SafeCast: value doesn't fit in 80 bits");
                    return uint80(value);
                }
            
                /**
                 * @dev Returns the downcasted uint72 from uint256, reverting on
                 * overflow (when the input is greater than largest uint72).
                 *
                 * Counterpart to Solidity's `uint72` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 72 bits
                 *
                 * _Available since v4.7._
                 */
                function toUint72(uint256 value) internal pure returns (uint72) {
                    require(value <= type(uint72).max, "SafeCast: value doesn't fit in 72 bits");
                    return uint72(value);
                }
            
                /**
                 * @dev Returns the downcasted uint64 from uint256, reverting on
                 * overflow (when the input is greater than largest uint64).
                 *
                 * Counterpart to Solidity's `uint64` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 64 bits
                 *
                 * _Available since v2.5._
                 */
                function toUint64(uint256 value) internal pure returns (uint64) {
                    require(value <= type(uint64).max, "SafeCast: value doesn't fit in 64 bits");
                    return uint64(value);
                }
            
                /**
                 * @dev Returns the downcasted uint56 from uint256, reverting on
                 * overflow (when the input is greater than largest uint56).
                 *
                 * Counterpart to Solidity's `uint56` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 56 bits
                 *
                 * _Available since v4.7._
                 */
                function toUint56(uint256 value) internal pure returns (uint56) {
                    require(value <= type(uint56).max, "SafeCast: value doesn't fit in 56 bits");
                    return uint56(value);
                }
            
                /**
                 * @dev Returns the downcasted uint48 from uint256, reverting on
                 * overflow (when the input is greater than largest uint48).
                 *
                 * Counterpart to Solidity's `uint48` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 48 bits
                 *
                 * _Available since v4.7._
                 */
                function toUint48(uint256 value) internal pure returns (uint48) {
                    require(value <= type(uint48).max, "SafeCast: value doesn't fit in 48 bits");
                    return uint48(value);
                }
            
                /**
                 * @dev Returns the downcasted uint40 from uint256, reverting on
                 * overflow (when the input is greater than largest uint40).
                 *
                 * Counterpart to Solidity's `uint40` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 40 bits
                 *
                 * _Available since v4.7._
                 */
                function toUint40(uint256 value) internal pure returns (uint40) {
                    require(value <= type(uint40).max, "SafeCast: value doesn't fit in 40 bits");
                    return uint40(value);
                }
            
                /**
                 * @dev Returns the downcasted uint32 from uint256, reverting on
                 * overflow (when the input is greater than largest uint32).
                 *
                 * Counterpart to Solidity's `uint32` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 32 bits
                 *
                 * _Available since v2.5._
                 */
                function toUint32(uint256 value) internal pure returns (uint32) {
                    require(value <= type(uint32).max, "SafeCast: value doesn't fit in 32 bits");
                    return uint32(value);
                }
            
                /**
                 * @dev Returns the downcasted uint24 from uint256, reverting on
                 * overflow (when the input is greater than largest uint24).
                 *
                 * Counterpart to Solidity's `uint24` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 24 bits
                 *
                 * _Available since v4.7._
                 */
                function toUint24(uint256 value) internal pure returns (uint24) {
                    require(value <= type(uint24).max, "SafeCast: value doesn't fit in 24 bits");
                    return uint24(value);
                }
            
                /**
                 * @dev Returns the downcasted uint16 from uint256, reverting on
                 * overflow (when the input is greater than largest uint16).
                 *
                 * Counterpart to Solidity's `uint16` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 16 bits
                 *
                 * _Available since v2.5._
                 */
                function toUint16(uint256 value) internal pure returns (uint16) {
                    require(value <= type(uint16).max, "SafeCast: value doesn't fit in 16 bits");
                    return uint16(value);
                }
            
                /**
                 * @dev Returns the downcasted uint8 from uint256, reverting on
                 * overflow (when the input is greater than largest uint8).
                 *
                 * Counterpart to Solidity's `uint8` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 8 bits
                 *
                 * _Available since v2.5._
                 */
                function toUint8(uint256 value) internal pure returns (uint8) {
                    require(value <= type(uint8).max, "SafeCast: value doesn't fit in 8 bits");
                    return uint8(value);
                }
            
                /**
                 * @dev Converts a signed int256 into an unsigned uint256.
                 *
                 * Requirements:
                 *
                 * - input must be greater than or equal to 0.
                 *
                 * _Available since v3.0._
                 */
                function toUint256(int256 value) internal pure returns (uint256) {
                    require(value >= 0, "SafeCast: value must be positive");
                    return uint256(value);
                }
            
                /**
                 * @dev Returns the downcasted int248 from int256, reverting on
                 * overflow (when the input is less than smallest int248 or
                 * greater than largest int248).
                 *
                 * Counterpart to Solidity's `int248` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 248 bits
                 *
                 * _Available since v4.7._
                 */
                function toInt248(int256 value) internal pure returns (int248) {
                    require(value >= type(int248).min && value <= type(int248).max, "SafeCast: value doesn't fit in 248 bits");
                    return int248(value);
                }
            
                /**
                 * @dev Returns the downcasted int240 from int256, reverting on
                 * overflow (when the input is less than smallest int240 or
                 * greater than largest int240).
                 *
                 * Counterpart to Solidity's `int240` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 240 bits
                 *
                 * _Available since v4.7._
                 */
                function toInt240(int256 value) internal pure returns (int240) {
                    require(value >= type(int240).min && value <= type(int240).max, "SafeCast: value doesn't fit in 240 bits");
                    return int240(value);
                }
            
                /**
                 * @dev Returns the downcasted int232 from int256, reverting on
                 * overflow (when the input is less than smallest int232 or
                 * greater than largest int232).
                 *
                 * Counterpart to Solidity's `int232` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 232 bits
                 *
                 * _Available since v4.7._
                 */
                function toInt232(int256 value) internal pure returns (int232) {
                    require(value >= type(int232).min && value <= type(int232).max, "SafeCast: value doesn't fit in 232 bits");
                    return int232(value);
                }
            
                /**
                 * @dev Returns the downcasted int224 from int256, reverting on
                 * overflow (when the input is less than smallest int224 or
                 * greater than largest int224).
                 *
                 * Counterpart to Solidity's `int224` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 224 bits
                 *
                 * _Available since v4.7._
                 */
                function toInt224(int256 value) internal pure returns (int224) {
                    require(value >= type(int224).min && value <= type(int224).max, "SafeCast: value doesn't fit in 224 bits");
                    return int224(value);
                }
            
                /**
                 * @dev Returns the downcasted int216 from int256, reverting on
                 * overflow (when the input is less than smallest int216 or
                 * greater than largest int216).
                 *
                 * Counterpart to Solidity's `int216` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 216 bits
                 *
                 * _Available since v4.7._
                 */
                function toInt216(int256 value) internal pure returns (int216) {
                    require(value >= type(int216).min && value <= type(int216).max, "SafeCast: value doesn't fit in 216 bits");
                    return int216(value);
                }
            
                /**
                 * @dev Returns the downcasted int208 from int256, reverting on
                 * overflow (when the input is less than smallest int208 or
                 * greater than largest int208).
                 *
                 * Counterpart to Solidity's `int208` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 208 bits
                 *
                 * _Available since v4.7._
                 */
                function toInt208(int256 value) internal pure returns (int208) {
                    require(value >= type(int208).min && value <= type(int208).max, "SafeCast: value doesn't fit in 208 bits");
                    return int208(value);
                }
            
                /**
                 * @dev Returns the downcasted int200 from int256, reverting on
                 * overflow (when the input is less than smallest int200 or
                 * greater than largest int200).
                 *
                 * Counterpart to Solidity's `int200` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 200 bits
                 *
                 * _Available since v4.7._
                 */
                function toInt200(int256 value) internal pure returns (int200) {
                    require(value >= type(int200).min && value <= type(int200).max, "SafeCast: value doesn't fit in 200 bits");
                    return int200(value);
                }
            
                /**
                 * @dev Returns the downcasted int192 from int256, reverting on
                 * overflow (when the input is less than smallest int192 or
                 * greater than largest int192).
                 *
                 * Counterpart to Solidity's `int192` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 192 bits
                 *
                 * _Available since v4.7._
                 */
                function toInt192(int256 value) internal pure returns (int192) {
                    require(value >= type(int192).min && value <= type(int192).max, "SafeCast: value doesn't fit in 192 bits");
                    return int192(value);
                }
            
                /**
                 * @dev Returns the downcasted int184 from int256, reverting on
                 * overflow (when the input is less than smallest int184 or
                 * greater than largest int184).
                 *
                 * Counterpart to Solidity's `int184` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 184 bits
                 *
                 * _Available since v4.7._
                 */
                function toInt184(int256 value) internal pure returns (int184) {
                    require(value >= type(int184).min && value <= type(int184).max, "SafeCast: value doesn't fit in 184 bits");
                    return int184(value);
                }
            
                /**
                 * @dev Returns the downcasted int176 from int256, reverting on
                 * overflow (when the input is less than smallest int176 or
                 * greater than largest int176).
                 *
                 * Counterpart to Solidity's `int176` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 176 bits
                 *
                 * _Available since v4.7._
                 */
                function toInt176(int256 value) internal pure returns (int176) {
                    require(value >= type(int176).min && value <= type(int176).max, "SafeCast: value doesn't fit in 176 bits");
                    return int176(value);
                }
            
                /**
                 * @dev Returns the downcasted int168 from int256, reverting on
                 * overflow (when the input is less than smallest int168 or
                 * greater than largest int168).
                 *
                 * Counterpart to Solidity's `int168` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 168 bits
                 *
                 * _Available since v4.7._
                 */
                function toInt168(int256 value) internal pure returns (int168) {
                    require(value >= type(int168).min && value <= type(int168).max, "SafeCast: value doesn't fit in 168 bits");
                    return int168(value);
                }
            
                /**
                 * @dev Returns the downcasted int160 from int256, reverting on
                 * overflow (when the input is less than smallest int160 or
                 * greater than largest int160).
                 *
                 * Counterpart to Solidity's `int160` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 160 bits
                 *
                 * _Available since v4.7._
                 */
                function toInt160(int256 value) internal pure returns (int160) {
                    require(value >= type(int160).min && value <= type(int160).max, "SafeCast: value doesn't fit in 160 bits");
                    return int160(value);
                }
            
                /**
                 * @dev Returns the downcasted int152 from int256, reverting on
                 * overflow (when the input is less than smallest int152 or
                 * greater than largest int152).
                 *
                 * Counterpart to Solidity's `int152` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 152 bits
                 *
                 * _Available since v4.7._
                 */
                function toInt152(int256 value) internal pure returns (int152) {
                    require(value >= type(int152).min && value <= type(int152).max, "SafeCast: value doesn't fit in 152 bits");
                    return int152(value);
                }
            
                /**
                 * @dev Returns the downcasted int144 from int256, reverting on
                 * overflow (when the input is less than smallest int144 or
                 * greater than largest int144).
                 *
                 * Counterpart to Solidity's `int144` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 144 bits
                 *
                 * _Available since v4.7._
                 */
                function toInt144(int256 value) internal pure returns (int144) {
                    require(value >= type(int144).min && value <= type(int144).max, "SafeCast: value doesn't fit in 144 bits");
                    return int144(value);
                }
            
                /**
                 * @dev Returns the downcasted int136 from int256, reverting on
                 * overflow (when the input is less than smallest int136 or
                 * greater than largest int136).
                 *
                 * Counterpart to Solidity's `int136` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 136 bits
                 *
                 * _Available since v4.7._
                 */
                function toInt136(int256 value) internal pure returns (int136) {
                    require(value >= type(int136).min && value <= type(int136).max, "SafeCast: value doesn't fit in 136 bits");
                    return int136(value);
                }
            
                /**
                 * @dev Returns the downcasted int128 from int256, reverting on
                 * overflow (when the input is less than smallest int128 or
                 * greater than largest int128).
                 *
                 * Counterpart to Solidity's `int128` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 128 bits
                 *
                 * _Available since v3.1._
                 */
                function toInt128(int256 value) internal pure returns (int128) {
                    require(value >= type(int128).min && value <= type(int128).max, "SafeCast: value doesn't fit in 128 bits");
                    return int128(value);
                }
            
                /**
                 * @dev Returns the downcasted int120 from int256, reverting on
                 * overflow (when the input is less than smallest int120 or
                 * greater than largest int120).
                 *
                 * Counterpart to Solidity's `int120` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 120 bits
                 *
                 * _Available since v4.7._
                 */
                function toInt120(int256 value) internal pure returns (int120) {
                    require(value >= type(int120).min && value <= type(int120).max, "SafeCast: value doesn't fit in 120 bits");
                    return int120(value);
                }
            
                /**
                 * @dev Returns the downcasted int112 from int256, reverting on
                 * overflow (when the input is less than smallest int112 or
                 * greater than largest int112).
                 *
                 * Counterpart to Solidity's `int112` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 112 bits
                 *
                 * _Available since v4.7._
                 */
                function toInt112(int256 value) internal pure returns (int112) {
                    require(value >= type(int112).min && value <= type(int112).max, "SafeCast: value doesn't fit in 112 bits");
                    return int112(value);
                }
            
                /**
                 * @dev Returns the downcasted int104 from int256, reverting on
                 * overflow (when the input is less than smallest int104 or
                 * greater than largest int104).
                 *
                 * Counterpart to Solidity's `int104` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 104 bits
                 *
                 * _Available since v4.7._
                 */
                function toInt104(int256 value) internal pure returns (int104) {
                    require(value >= type(int104).min && value <= type(int104).max, "SafeCast: value doesn't fit in 104 bits");
                    return int104(value);
                }
            
                /**
                 * @dev Returns the downcasted int96 from int256, reverting on
                 * overflow (when the input is less than smallest int96 or
                 * greater than largest int96).
                 *
                 * Counterpart to Solidity's `int96` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 96 bits
                 *
                 * _Available since v4.7._
                 */
                function toInt96(int256 value) internal pure returns (int96) {
                    require(value >= type(int96).min && value <= type(int96).max, "SafeCast: value doesn't fit in 96 bits");
                    return int96(value);
                }
            
                /**
                 * @dev Returns the downcasted int88 from int256, reverting on
                 * overflow (when the input is less than smallest int88 or
                 * greater than largest int88).
                 *
                 * Counterpart to Solidity's `int88` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 88 bits
                 *
                 * _Available since v4.7._
                 */
                function toInt88(int256 value) internal pure returns (int88) {
                    require(value >= type(int88).min && value <= type(int88).max, "SafeCast: value doesn't fit in 88 bits");
                    return int88(value);
                }
            
                /**
                 * @dev Returns the downcasted int80 from int256, reverting on
                 * overflow (when the input is less than smallest int80 or
                 * greater than largest int80).
                 *
                 * Counterpart to Solidity's `int80` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 80 bits
                 *
                 * _Available since v4.7._
                 */
                function toInt80(int256 value) internal pure returns (int80) {
                    require(value >= type(int80).min && value <= type(int80).max, "SafeCast: value doesn't fit in 80 bits");
                    return int80(value);
                }
            
                /**
                 * @dev Returns the downcasted int72 from int256, reverting on
                 * overflow (when the input is less than smallest int72 or
                 * greater than largest int72).
                 *
                 * Counterpart to Solidity's `int72` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 72 bits
                 *
                 * _Available since v4.7._
                 */
                function toInt72(int256 value) internal pure returns (int72) {
                    require(value >= type(int72).min && value <= type(int72).max, "SafeCast: value doesn't fit in 72 bits");
                    return int72(value);
                }
            
                /**
                 * @dev Returns the downcasted int64 from int256, reverting on
                 * overflow (when the input is less than smallest int64 or
                 * greater than largest int64).
                 *
                 * Counterpart to Solidity's `int64` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 64 bits
                 *
                 * _Available since v3.1._
                 */
                function toInt64(int256 value) internal pure returns (int64) {
                    require(value >= type(int64).min && value <= type(int64).max, "SafeCast: value doesn't fit in 64 bits");
                    return int64(value);
                }
            
                /**
                 * @dev Returns the downcasted int56 from int256, reverting on
                 * overflow (when the input is less than smallest int56 or
                 * greater than largest int56).
                 *
                 * Counterpart to Solidity's `int56` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 56 bits
                 *
                 * _Available since v4.7._
                 */
                function toInt56(int256 value) internal pure returns (int56) {
                    require(value >= type(int56).min && value <= type(int56).max, "SafeCast: value doesn't fit in 56 bits");
                    return int56(value);
                }
            
                /**
                 * @dev Returns the downcasted int48 from int256, reverting on
                 * overflow (when the input is less than smallest int48 or
                 * greater than largest int48).
                 *
                 * Counterpart to Solidity's `int48` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 48 bits
                 *
                 * _Available since v4.7._
                 */
                function toInt48(int256 value) internal pure returns (int48) {
                    require(value >= type(int48).min && value <= type(int48).max, "SafeCast: value doesn't fit in 48 bits");
                    return int48(value);
                }
            
                /**
                 * @dev Returns the downcasted int40 from int256, reverting on
                 * overflow (when the input is less than smallest int40 or
                 * greater than largest int40).
                 *
                 * Counterpart to Solidity's `int40` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 40 bits
                 *
                 * _Available since v4.7._
                 */
                function toInt40(int256 value) internal pure returns (int40) {
                    require(value >= type(int40).min && value <= type(int40).max, "SafeCast: value doesn't fit in 40 bits");
                    return int40(value);
                }
            
                /**
                 * @dev Returns the downcasted int32 from int256, reverting on
                 * overflow (when the input is less than smallest int32 or
                 * greater than largest int32).
                 *
                 * Counterpart to Solidity's `int32` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 32 bits
                 *
                 * _Available since v3.1._
                 */
                function toInt32(int256 value) internal pure returns (int32) {
                    require(value >= type(int32).min && value <= type(int32).max, "SafeCast: value doesn't fit in 32 bits");
                    return int32(value);
                }
            
                /**
                 * @dev Returns the downcasted int24 from int256, reverting on
                 * overflow (when the input is less than smallest int24 or
                 * greater than largest int24).
                 *
                 * Counterpart to Solidity's `int24` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 24 bits
                 *
                 * _Available since v4.7._
                 */
                function toInt24(int256 value) internal pure returns (int24) {
                    require(value >= type(int24).min && value <= type(int24).max, "SafeCast: value doesn't fit in 24 bits");
                    return int24(value);
                }
            
                /**
                 * @dev Returns the downcasted int16 from int256, reverting on
                 * overflow (when the input is less than smallest int16 or
                 * greater than largest int16).
                 *
                 * Counterpart to Solidity's `int16` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 16 bits
                 *
                 * _Available since v3.1._
                 */
                function toInt16(int256 value) internal pure returns (int16) {
                    require(value >= type(int16).min && value <= type(int16).max, "SafeCast: value doesn't fit in 16 bits");
                    return int16(value);
                }
            
                /**
                 * @dev Returns the downcasted int8 from int256, reverting on
                 * overflow (when the input is less than smallest int8 or
                 * greater than largest int8).
                 *
                 * Counterpart to Solidity's `int8` operator.
                 *
                 * Requirements:
                 *
                 * - input must fit into 8 bits
                 *
                 * _Available since v3.1._
                 */
                function toInt8(int256 value) internal pure returns (int8) {
                    require(value >= type(int8).min && value <= type(int8).max, "SafeCast: value doesn't fit in 8 bits");
                    return int8(value);
                }
            
                /**
                 * @dev Converts an unsigned uint256 into a signed int256.
                 *
                 * Requirements:
                 *
                 * - input must be less than or equal to maxInt256.
                 *
                 * _Available since v3.0._
                 */
                function toInt256(uint256 value) internal pure returns (int256) {
                    // Note: Unsafe cast below is okay because `type(int256).max` is guaranteed to be positive
                    require(value <= uint256(type(int256).max), "SafeCast: value doesn't fit in an int256");
                    return int256(value);
                }
            }
            
            
            // File contracts/routers/UnoswapV3Router.sol
            
            
            pragma solidity 0.8.17;
            
            
            
            
            
            
            
            
            
            contract UnoswapV3Router is EthReceiver, IUniswapV3SwapCallback {
                using Address for address payable;
                using SafeERC20 for IERC20;
            
                error EmptyPools();
                error BadPool();
            
                uint256 private constant _ONE_FOR_ZERO_MASK = 1 << 255;
                uint256 private constant _WETH_UNWRAP_MASK = 1 << 253;
                bytes32 private constant _POOL_INIT_CODE_HASH = 0xe34f199b19b2b4f47f68442619d555527d244f78a3297ea89325f843f87b8b54;
                bytes32 private constant _FF_FACTORY = 0xff1F98431c8aD98523631AE4a59f267346ea31F9840000000000000000000000;
                // concatenation of token0(), token1() fee(), transfer() and transferFrom() selectors
                bytes32 private constant _SELECTORS = 0x0dfe1681d21220a7ddca3f43a9059cbb23b872dd000000000000000000000000;
                uint256 private constant _ADDRESS_MASK =   0x000000000000000000000000ffffffffffffffffffffffffffffffffffffffff;
                /// @dev The minimum value that can be returned from #getSqrtRatioAtTick. Equivalent to getSqrtRatioAtTick(MIN_TICK)
                uint160 private constant _MIN_SQRT_RATIO = 4295128739 + 1;
                /// @dev The maximum value that can be returned from #getSqrtRatioAtTick. Equivalent to getSqrtRatioAtTick(MAX_TICK)
                uint160 private constant _MAX_SQRT_RATIO = 1461446703485210103287273052203988822378723970342 - 1;
                IWETH private immutable _WETH;  // solhint-disable-line var-name-mixedcase
            
                constructor(IWETH weth) {
                    _WETH = weth;
                }
            
                /// @notice Same as `uniswapV3SwapTo` but calls permit first,
                /// allowing to approve token spending and make a swap in one transaction.
                /// @param recipient Address that will receive swap funds
                /// @param srcToken Source token
                /// @param amount Amount of source tokens to swap
                /// @param minReturn Minimal allowed returnAmount to make transaction commit
                /// @param pools Pools chain used for swaps. Pools src and dst tokens should match to make swap happen
                /// @param permit Should contain valid permit that can be used in `IERC20Permit.permit` calls.
                /// See tests for examples
                function uniswapV3SwapToWithPermit(
                    address payable recipient,
                    IERC20 srcToken,
                    uint256 amount,
                    uint256 minReturn,
                    uint256[] calldata pools,
                    bytes calldata permit
                ) external returns(uint256 returnAmount) {
                    srcToken.safePermit(permit);
                    return _uniswapV3Swap(recipient, amount, minReturn, pools);
                }
            
                /// @notice Same as `uniswapV3SwapTo` but uses `msg.sender` as recipient
                /// @param amount Amount of source tokens to swap
                /// @param minReturn Minimal allowed returnAmount to make transaction commit
                /// @param pools Pools chain used for swaps. Pools src and dst tokens should match to make swap happen
                function uniswapV3Swap(
                    uint256 amount,
                    uint256 minReturn,
                    uint256[] calldata pools
                ) external payable returns(uint256 returnAmount) {
                    return _uniswapV3Swap(payable(msg.sender), amount, minReturn, pools);
                }
            
                /// @notice Performs swap using Uniswap V3 exchange. Wraps and unwraps ETH if required.
                /// Sending non-zero `msg.value` for anything but ETH swaps is prohibited
                /// @param recipient Address that will receive swap funds
                /// @param amount Amount of source tokens to swap
                /// @param minReturn Minimal allowed returnAmount to make transaction commit
                /// @param pools Pools chain used for swaps. Pools src and dst tokens should match to make swap happen
                function uniswapV3SwapTo(
                    address payable recipient,
                    uint256 amount,
                    uint256 minReturn,
                    uint256[] calldata pools
                ) external payable returns(uint256 returnAmount) {
                    return _uniswapV3Swap(recipient, amount, minReturn, pools);
                }
            
                function _uniswapV3Swap(
                    address payable recipient,
                    uint256 amount,
                    uint256 minReturn,
                    uint256[] calldata pools
                ) private returns(uint256 returnAmount) {
                    unchecked {
                        uint256 len = pools.length;
                        if (len == 0) revert EmptyPools();
                        uint256 lastIndex = len - 1;
                        returnAmount = amount;
                        bool wrapWeth = msg.value > 0;
                        bool unwrapWeth = pools[lastIndex] & _WETH_UNWRAP_MASK > 0;
                        if (wrapWeth) {
                            if (msg.value != amount) revert RouterErrors.InvalidMsgValue();
                            _WETH.deposit{value: amount}();
                        }
                        if (len > 1) {
                            returnAmount = _makeSwap(address(this), wrapWeth ? address(this) : msg.sender, pools[0], returnAmount);
            
                            for (uint256 i = 1; i < lastIndex; i++) {
                                returnAmount = _makeSwap(address(this), address(this), pools[i], returnAmount);
                            }
                            returnAmount = _makeSwap(unwrapWeth ? address(this) : recipient, address(this), pools[lastIndex], returnAmount);
                        } else {
                            returnAmount = _makeSwap(unwrapWeth ? address(this) : recipient, wrapWeth ? address(this) : msg.sender, pools[0], returnAmount);
                        }
            
                        if (returnAmount < minReturn) revert RouterErrors.ReturnAmountIsNotEnough();
            
                        if (unwrapWeth) {
                            _WETH.withdraw(returnAmount);
                            recipient.sendValue(returnAmount);
                        }
                    }
                }
            
                /// @inheritdoc IUniswapV3SwapCallback
                function uniswapV3SwapCallback(
                    int256 amount0Delta,
                    int256 amount1Delta,
                    bytes calldata /* data */
                ) external override {
                    assembly {  // solhint-disable-line no-inline-assembly
                        function reRevert() {
                            returndatacopy(0, 0, returndatasize())
                            revert(0, returndatasize())
                        }
            
                        function validateERC20Transfer(status) {
                            if iszero(status) {
                                reRevert()
                            }
                            let success := or(
                                iszero(returndatasize()),                       // empty return data
                                and(gt(returndatasize(), 31), eq(mload(0), 1))  // true in return data
                            )
                            if iszero(success) {
                                mstore(0, 0xf27f64e400000000000000000000000000000000000000000000000000000000)  // ERC20TransferFailed()
                                revert(0, 4)
                            }
                        }
            
                        let emptyPtr := mload(0x40)
                        let resultPtr := add(emptyPtr, 0x15)  // 0x15 = _FF_FACTORY size
            
                        mstore(emptyPtr, _SELECTORS)
                        if iszero(staticcall(gas(), caller(), emptyPtr, 0x4, resultPtr, 0x20)) {
                            reRevert()
                        }
                        if iszero(staticcall(gas(), caller(), add(emptyPtr, 0x4), 0x4, add(resultPtr, 0x20), 0x20)) {
                            reRevert()
                        }
                        if iszero(staticcall(gas(), caller(), add(emptyPtr, 0x8), 0x4, add(resultPtr, 0x40), 0x20)) {
                            reRevert()
                        }
            
                        let token
                        let amount
                        switch sgt(amount0Delta, 0)
                        case 1 {
                            token := mload(resultPtr)
                            amount := amount0Delta
                        }
                        default {
                            token := mload(add(resultPtr, 0x20))
                            amount := amount1Delta
                        }
            
                        mstore(emptyPtr, _FF_FACTORY)
                        mstore(resultPtr, keccak256(resultPtr, 0x60)) // Compute the inner hash in-place
                        mstore(add(resultPtr, 0x20), _POOL_INIT_CODE_HASH)
                        let pool := and(keccak256(emptyPtr, 0x55), _ADDRESS_MASK)
                        if xor(pool, caller()) {
                            mstore(0, 0xb2c0272200000000000000000000000000000000000000000000000000000000)  // BadPool()
                            revert(0, 4)
                        }
            
                        let payer := calldataload(0x84)
                        mstore(emptyPtr, _SELECTORS)
                        switch eq(payer, address())
                        case 1 {
                            // token.safeTransfer(msg.sender,amount)
                            mstore(add(emptyPtr, 0x10), caller())
                            mstore(add(emptyPtr, 0x30), amount)
                            validateERC20Transfer(
                                call(gas(), token, 0, add(emptyPtr, 0x0c), 0x44, 0, 0x20)
                            )
                        }
                        default {
                            // token.safeTransferFrom(payer, msg.sender, amount);
                            mstore(add(emptyPtr, 0x14), payer)
                            mstore(add(emptyPtr, 0x34), caller())
                            mstore(add(emptyPtr, 0x54), amount)
                            validateERC20Transfer(
                                call(gas(), token, 0, add(emptyPtr, 0x10), 0x64, 0, 0x20)
                            )
                        }
                    }
                }
            
                function _makeSwap(address recipient, address payer, uint256 pool, uint256 amount) private returns (uint256) {
                    bool zeroForOne = pool & _ONE_FOR_ZERO_MASK == 0;
                    if (zeroForOne) {
                        (, int256 amount1) = IUniswapV3Pool(address(uint160(pool))).swap(
                            recipient,
                            zeroForOne,
                            SafeCast.toInt256(amount),
                            _MIN_SQRT_RATIO,
                            abi.encode(payer)
                        );
                        return SafeCast.toUint256(-amount1);
                    } else {
                        (int256 amount0,) = IUniswapV3Pool(address(uint160(pool))).swap(
                            recipient,
                            zeroForOne,
                            SafeCast.toInt256(amount),
                            _MAX_SQRT_RATIO,
                            abi.encode(payer)
                        );
                        return SafeCast.toUint256(-amount0);
                    }
                }
            }
            
            
            // File @1inch/solidity-utils/contracts/[email protected]
            
            
            pragma solidity ^0.8.0;
            
            abstract contract OnlyWethReceiver is EthReceiver {
                address private immutable _WETH;  // solhint-disable-line var-name-mixedcase
            
                constructor(address weth) {
                    _WETH = address(weth);
                }
            
                function _receive() internal virtual override {
                    if (msg.sender != _WETH) revert EthDepositRejected();
                }
            }
            
            
            // File @openzeppelin/contracts/interfaces/[email protected]
            
            // OpenZeppelin Contracts v4.4.1 (interfaces/IERC1271.sol)
            
            pragma solidity ^0.8.0;
            
            /**
             * @dev Interface of the ERC1271 standard signature validation method for
             * contracts as defined in https://eips.ethereum.org/EIPS/eip-1271[ERC-1271].
             *
             * _Available since v4.1._
             */
            interface IERC1271 {
                /**
                 * @dev Should return whether the signature provided is valid for the provided data
                 * @param hash      Hash of the data to be signed
                 * @param signature Signature byte array associated with _data
                 */
                function isValidSignature(bytes32 hash, bytes memory signature) external view returns (bytes4 magicValue);
            }
            
            
            // File @1inch/solidity-utils/contracts/libraries/[email protected]
            
            
            pragma solidity ^0.8.0;
            
            library ECDSA {
                // EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
                // unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
                // the valid range for s in (301): 0 < s < secp256k1n ÷ 2 + 1, and for v in (302): v ∈ {27, 28}. Most
                // signatures from current libraries generate a unique signature with an s-value in the lower half order.
                //
                // If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
                // with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
                // vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
                // these malleable signatures as well.
                uint256 private constant _S_BOUNDARY = 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0 + 1;
                uint256 private constant _COMPACT_S_MASK = 0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff;
                uint256 private constant _COMPACT_V_SHIFT = 255;
            
                function recover(bytes32 hash, uint8 v, bytes32 r, bytes32 s) internal view returns(address signer) {
                    /// @solidity memory-safe-assembly
                    assembly { // solhint-disable-line no-inline-assembly
                        if lt(s, _S_BOUNDARY) {
                            let ptr := mload(0x40)
            
                            mstore(ptr, hash)
                            mstore(add(ptr, 0x20), v)
                            mstore(add(ptr, 0x40), r)
                            mstore(add(ptr, 0x60), s)
                            mstore(0, 0)
                            pop(staticcall(gas(), 0x1, ptr, 0x80, 0, 0x20))
                            signer := mload(0)
                        }
                    }
                }
            
                function recover(bytes32 hash, bytes32 r, bytes32 vs) internal view returns(address signer) {
                    /// @solidity memory-safe-assembly
                    assembly { // solhint-disable-line no-inline-assembly
                        let s := and(vs, _COMPACT_S_MASK)
                        if lt(s, _S_BOUNDARY) {
                            let ptr := mload(0x40)
            
                            mstore(ptr, hash)
                            mstore(add(ptr, 0x20), add(27, shr(_COMPACT_V_SHIFT, vs)))
                            mstore(add(ptr, 0x40), r)
                            mstore(add(ptr, 0x60), s)
                            mstore(0, 0)
                            pop(staticcall(gas(), 0x1, ptr, 0x80, 0, 0x20))
                            signer := mload(0)
                        }
                    }
                }
            
                /// WARNING!!!
                /// There is a known signature malleability issue with two representations of signatures!
                /// Even though this function is able to verify both standard 65-byte and compact 64-byte EIP-2098 signatures
                /// one should never use raw signatures for any kind of invalidation logic in their code.
                /// As the standard and compact representations are interchangeable any invalidation logic that relies on
                /// signature uniqueness will get rekt.
                /// More info: https://github.com/OpenZeppelin/openzeppelin-contracts/security/advisories/GHSA-4h98-2769-gh6h
                function recover(bytes32 hash, bytes calldata signature) internal view returns(address signer) {
                    /// @solidity memory-safe-assembly
                    assembly { // solhint-disable-line no-inline-assembly
                        let ptr := mload(0x40)
            
                        // memory[ptr:ptr+0x80] = (hash, v, r, s)
                        switch signature.length
                        case 65 {
                            // memory[ptr+0x20:ptr+0x80] = (v, r, s)
                            mstore(add(ptr, 0x20), byte(0, calldataload(add(signature.offset, 0x40))))
                            calldatacopy(add(ptr, 0x40), signature.offset, 0x40)
                        }
                        case 64 {
                            // memory[ptr+0x20:ptr+0x80] = (v, r, s)
                            let vs := calldataload(add(signature.offset, 0x20))
                            mstore(add(ptr, 0x20), add(27, shr(_COMPACT_V_SHIFT, vs)))
                            calldatacopy(add(ptr, 0x40), signature.offset, 0x20)
                            mstore(add(ptr, 0x60), and(vs, _COMPACT_S_MASK))
                        }
                        default {
                            ptr := 0
                        }
            
                        if ptr {
                            if lt(mload(add(ptr, 0x60)), _S_BOUNDARY) {
                                // memory[ptr:ptr+0x20] = (hash)
                                mstore(ptr, hash)
            
                                mstore(0, 0)
                                pop(staticcall(gas(), 0x1, ptr, 0x80, 0, 0x20))
                                signer := mload(0)
                            }
                        }
                    }
                }
            
                function recoverOrIsValidSignature(address signer, bytes32 hash, bytes calldata signature) internal view returns(bool success) {
                    if (signer == address(0)) return false;
                    if ((signature.length == 64 || signature.length == 65) && recover(hash, signature) == signer) {
                        return true;
                    }
                    return isValidSignature(signer, hash, signature);
                }
            
                function recoverOrIsValidSignature(address signer, bytes32 hash, uint8 v, bytes32 r, bytes32 s) internal view returns(bool success) {
                    if (signer == address(0)) return false;
                    if (recover(hash, v, r, s) == signer) {
                        return true;
                    }
                    return isValidSignature(signer, hash, v, r, s);
                }
            
                function recoverOrIsValidSignature(address signer, bytes32 hash, bytes32 r, bytes32 vs) internal view returns(bool success) {
                    if (signer == address(0)) return false;
                    if (recover(hash, r, vs) == signer) {
                        return true;
                    }
                    return isValidSignature(signer, hash, r, vs);
                }
            
                function recoverOrIsValidSignature65(address signer, bytes32 hash, bytes32 r, bytes32 vs) internal view returns(bool success) {
                    if (signer == address(0)) return false;
                    if (recover(hash, r, vs) == signer) {
                        return true;
                    }
                    return isValidSignature65(signer, hash, r, vs);
                }
            
                function isValidSignature(address signer, bytes32 hash, bytes calldata signature) internal view returns(bool success) {
                    // (bool success, bytes memory data) = signer.staticcall(abi.encodeWithSelector(IERC1271.isValidSignature.selector, hash, signature));
                    // return success && data.length >= 4 && abi.decode(data, (bytes4)) == IERC1271.isValidSignature.selector;
                    bytes4 selector = IERC1271.isValidSignature.selector;
                    /// @solidity memory-safe-assembly
                    assembly { // solhint-disable-line no-inline-assembly
                        let ptr := mload(0x40)
            
                        mstore(ptr, selector)
                        mstore(add(ptr, 0x04), hash)
                        mstore(add(ptr, 0x24), 0x40)
                        mstore(add(ptr, 0x44), signature.length)
                        calldatacopy(add(ptr, 0x64), signature.offset, signature.length)
                        if staticcall(gas(), signer, ptr, add(0x64, signature.length), 0, 0x20) {
                            success := and(eq(selector, mload(0)), eq(returndatasize(), 0x20))
                        }
                    }
                }
            
                function isValidSignature(address signer, bytes32 hash, uint8 v, bytes32 r, bytes32 s) internal view returns(bool success) {
                    bytes4 selector = IERC1271.isValidSignature.selector;
                    /// @solidity memory-safe-assembly
                    assembly { // solhint-disable-line no-inline-assembly
                        let ptr := mload(0x40)
            
                        mstore(ptr, selector)
                        mstore(add(ptr, 0x04), hash)
                        mstore(add(ptr, 0x24), 0x40)
                        mstore(add(ptr, 0x44), 65)
                        mstore(add(ptr, 0x64), r)
                        mstore(add(ptr, 0x84), s)
                        mstore8(add(ptr, 0xa4), v)
                        if staticcall(gas(), signer, ptr, 0xa5, 0, 0x20) {
                            success := and(eq(selector, mload(0)), eq(returndatasize(), 0x20))
                        }
                    }
                }
            
                function isValidSignature(address signer, bytes32 hash, bytes32 r, bytes32 vs) internal view returns(bool success) {
                    // (bool success, bytes memory data) = signer.staticcall(abi.encodeWithSelector(IERC1271.isValidSignature.selector, hash, abi.encodePacked(r, vs)));
                    // return success && data.length >= 4 && abi.decode(data, (bytes4)) == IERC1271.isValidSignature.selector;
                    bytes4 selector = IERC1271.isValidSignature.selector;
                    /// @solidity memory-safe-assembly
                    assembly { // solhint-disable-line no-inline-assembly
                        let ptr := mload(0x40)
            
                        mstore(ptr, selector)
                        mstore(add(ptr, 0x04), hash)
                        mstore(add(ptr, 0x24), 0x40)
                        mstore(add(ptr, 0x44), 64)
                        mstore(add(ptr, 0x64), r)
                        mstore(add(ptr, 0x84), vs)
                        if staticcall(gas(), signer, ptr, 0xa4, 0, 0x20) {
                            success := and(eq(selector, mload(0)), eq(returndatasize(), 0x20))
                        }
                    }
                }
            
                function isValidSignature65(address signer, bytes32 hash, bytes32 r, bytes32 vs) internal view returns(bool success) {
                    // (bool success, bytes memory data) = signer.staticcall(abi.encodeWithSelector(IERC1271.isValidSignature.selector, hash, abi.encodePacked(r, vs & ~uint256(1 << 255), uint8(vs >> 255))));
                    // return success && data.length >= 4 && abi.decode(data, (bytes4)) == IERC1271.isValidSignature.selector;
                    bytes4 selector = IERC1271.isValidSignature.selector;
                    /// @solidity memory-safe-assembly
                    assembly { // solhint-disable-line no-inline-assembly
                        let ptr := mload(0x40)
            
                        mstore(ptr, selector)
                        mstore(add(ptr, 0x04), hash)
                        mstore(add(ptr, 0x24), 0x40)
                        mstore(add(ptr, 0x44), 65)
                        mstore(add(ptr, 0x64), r)
                        mstore(add(ptr, 0x84), and(vs, _COMPACT_S_MASK))
                        mstore8(add(ptr, 0xa4), add(27, shr(_COMPACT_V_SHIFT, vs)))
                        if staticcall(gas(), signer, ptr, 0xa5, 0, 0x20) {
                            success := and(eq(selector, mload(0)), eq(returndatasize(), 0x20))
                        }
                    }
                }
            
                function toEthSignedMessageHash(bytes32 hash) internal pure returns (bytes32 res) {
                    // 32 is the length in bytes of hash, enforced by the type signature above
                    // return keccak256(abi.encodePacked("\x19Ethereum Signed Message:\n32", hash));
                    /// @solidity memory-safe-assembly
                    assembly { // solhint-disable-line no-inline-assembly
                        mstore(0, 0x19457468657265756d205369676e6564204d6573736167653a0a333200000000) // "\x19Ethereum Signed Message:\n32"
                        mstore(28, hash)
                        res := keccak256(0, 60)
                    }
                }
            
                function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash) internal pure returns (bytes32 res) {
                    // return keccak256(abi.encodePacked("\x19\x01", domainSeparator, structHash));
                    /// @solidity memory-safe-assembly
                    assembly { // solhint-disable-line no-inline-assembly
                        let ptr := mload(0x40)
                        mstore(ptr, 0x1901000000000000000000000000000000000000000000000000000000000000) // "\x19\x01"
                        mstore(add(ptr, 0x02), domainSeparator)
                        mstore(add(ptr, 0x22), structHash)
                        res := keccak256(ptr, 66)
                    }
                }
            }
            
            
            // File @1inch/limit-order-protocol/contracts/[email protected]
            
            
            pragma solidity 0.8.17;
            
            library OrderRFQLib {
                struct OrderRFQ {
                    uint256 info;  // lowest 64 bits is the order id, next 64 bits is the expiration timestamp
                    address makerAsset;
                    address takerAsset;
                    address maker;
                    address allowedSender;  // equals to Zero address on public orders
                    uint256 makingAmount;
                    uint256 takingAmount;
                }
            
                bytes32 constant internal _LIMIT_ORDER_RFQ_TYPEHASH = keccak256(
                    "OrderRFQ("
                        "uint256 info,"
                        "address makerAsset,"
                        "address takerAsset,"
                        "address maker,"
                        "address allowedSender,"
                        "uint256 makingAmount,"
                        "uint256 takingAmount"
                    ")"
                );
            
                function hash(OrderRFQ memory order, bytes32 domainSeparator) internal pure returns(bytes32 result) {
                    bytes32 typehash = _LIMIT_ORDER_RFQ_TYPEHASH;
                    bytes32 orderHash;
                    // this assembly is memory unsafe :(
                    assembly { // solhint-disable-line no-inline-assembly
                        let ptr := sub(order, 0x20)
            
                        // keccak256(abi.encode(_LIMIT_ORDER_RFQ_TYPEHASH, order));
                        let tmp := mload(ptr)
                        mstore(ptr, typehash)
                        orderHash := keccak256(ptr, 0x100)
                        mstore(ptr, tmp)
                    }
                    return ECDSA.toTypedDataHash(domainSeparator, orderHash);
                }
            }
            
            
            // File @openzeppelin/contracts/utils/[email protected]
            
            // OpenZeppelin Contracts (last updated v4.7.0) (utils/Strings.sol)
            
            pragma solidity ^0.8.0;
            
            /**
             * @dev String operations.
             */
            library Strings {
                bytes16 private constant _HEX_SYMBOLS = "0123456789abcdef";
                uint8 private constant _ADDRESS_LENGTH = 20;
            
                /**
                 * @dev Converts a `uint256` to its ASCII `string` decimal representation.
                 */
                function toString(uint256 value) internal pure returns (string memory) {
                    // Inspired by OraclizeAPI's implementation - MIT licence
                    // https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol
            
                    if (value == 0) {
                        return "0";
                    }
                    uint256 temp = value;
                    uint256 digits;
                    while (temp != 0) {
                        digits++;
                        temp /= 10;
                    }
                    bytes memory buffer = new bytes(digits);
                    while (value != 0) {
                        digits -= 1;
                        buffer[digits] = bytes1(uint8(48 + uint256(value % 10)));
                        value /= 10;
                    }
                    return string(buffer);
                }
            
                /**
                 * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
                 */
                function toHexString(uint256 value) internal pure returns (string memory) {
                    if (value == 0) {
                        return "0x00";
                    }
                    uint256 temp = value;
                    uint256 length = 0;
                    while (temp != 0) {
                        length++;
                        temp >>= 8;
                    }
                    return toHexString(value, length);
                }
            
                /**
                 * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
                 */
                function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
                    bytes memory buffer = new bytes(2 * length + 2);
                    buffer[0] = "0";
                    buffer[1] = "x";
                    for (uint256 i = 2 * length + 1; i > 1; --i) {
                        buffer[i] = _HEX_SYMBOLS[value & 0xf];
                        value >>= 4;
                    }
                    require(value == 0, "Strings: hex length insufficient");
                    return string(buffer);
                }
            
                /**
                 * @dev Converts an `address` with fixed length of 20 bytes to its not checksummed ASCII `string` hexadecimal representation.
                 */
                function toHexString(address addr) internal pure returns (string memory) {
                    return toHexString(uint256(uint160(addr)), _ADDRESS_LENGTH);
                }
            }
            
            
            // File @openzeppelin/contracts/utils/cryptography/[email protected]
            
            // OpenZeppelin Contracts v4.4.1 (utils/cryptography/draft-EIP712.sol)
            
            pragma solidity ^0.8.0;
            
            /**
             * @dev https://eips.ethereum.org/EIPS/eip-712[EIP 712] is a standard for hashing and signing of typed structured data.
             *
             * The encoding specified in the EIP is very generic, and such a generic implementation in Solidity is not feasible,
             * thus this contract does not implement the encoding itself. Protocols need to implement the type-specific encoding
             * they need in their contracts using a combination of `abi.encode` and `keccak256`.
             *
             * This contract implements the EIP 712 domain separator ({_domainSeparatorV4}) that is used as part of the encoding
             * scheme, and the final step of the encoding to obtain the message digest that is then signed via ECDSA
             * ({_hashTypedDataV4}).
             *
             * The implementation of the domain separator was designed to be as efficient as possible while still properly updating
             * the chain id to protect against replay attacks on an eventual fork of the chain.
             *
             * NOTE: This contract implements the version of the encoding known as "v4", as implemented by the JSON RPC method
             * https://docs.metamask.io/guide/signing-data.html[`eth_signTypedDataV4` in MetaMask].
             *
             * _Available since v3.4._
             */
            abstract contract EIP712 {
                /* solhint-disable var-name-mixedcase */
                // Cache the domain separator as an immutable value, but also store the chain id that it corresponds to, in order to
                // invalidate the cached domain separator if the chain id changes.
                bytes32 private immutable _CACHED_DOMAIN_SEPARATOR;
                uint256 private immutable _CACHED_CHAIN_ID;
                address private immutable _CACHED_THIS;
            
                bytes32 private immutable _HASHED_NAME;
                bytes32 private immutable _HASHED_VERSION;
                bytes32 private immutable _TYPE_HASH;
            
                /* solhint-enable var-name-mixedcase */
            
                /**
                 * @dev Initializes the domain separator and parameter caches.
                 *
                 * The meaning of `name` and `version` is specified in
                 * https://eips.ethereum.org/EIPS/eip-712#definition-of-domainseparator[EIP 712]:
                 *
                 * - `name`: the user readable name of the signing domain, i.e. the name of the DApp or the protocol.
                 * - `version`: the current major version of the signing domain.
                 *
                 * NOTE: These parameters cannot be changed except through a xref:learn::upgrading-smart-contracts.adoc[smart
                 * contract upgrade].
                 */
                constructor(string memory name, string memory version) {
                    bytes32 hashedName = keccak256(bytes(name));
                    bytes32 hashedVersion = keccak256(bytes(version));
                    bytes32 typeHash = keccak256(
                        "EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"
                    );
                    _HASHED_NAME = hashedName;
                    _HASHED_VERSION = hashedVersion;
                    _CACHED_CHAIN_ID = block.chainid;
                    _CACHED_DOMAIN_SEPARATOR = _buildDomainSeparator(typeHash, hashedName, hashedVersion);
                    _CACHED_THIS = address(this);
                    _TYPE_HASH = typeHash;
                }
            
                /**
                 * @dev Returns the domain separator for the current chain.
                 */
                function _domainSeparatorV4() internal view returns (bytes32) {
                    if (address(this) == _CACHED_THIS && block.chainid == _CACHED_CHAIN_ID) {
                        return _CACHED_DOMAIN_SEPARATOR;
                    } else {
                        return _buildDomainSeparator(_TYPE_HASH, _HASHED_NAME, _HASHED_VERSION);
                    }
                }
            
                function _buildDomainSeparator(
                    bytes32 typeHash,
                    bytes32 nameHash,
                    bytes32 versionHash
                ) private view returns (bytes32) {
                    return keccak256(abi.encode(typeHash, nameHash, versionHash, block.chainid, address(this)));
                }
            
                /**
                 * @dev Given an already https://eips.ethereum.org/EIPS/eip-712#definition-of-hashstruct[hashed struct], this
                 * function returns the hash of the fully encoded EIP712 message for this domain.
                 *
                 * This hash can be used together with {ECDSA-recover} to obtain the signer of a message. For example:
                 *
                 * ```solidity
                 * bytes32 digest = _hashTypedDataV4(keccak256(abi.encode(
                 *     keccak256("Mail(address to,string contents)"),
                 *     mailTo,
                 *     keccak256(bytes(mailContents))
                 * )));
                 * address signer = ECDSA.recover(digest, signature);
                 * ```
                 */
                function _hashTypedDataV4(bytes32 structHash) internal view virtual returns (bytes32) {
                    return ECDSA.toTypedDataHash(_domainSeparatorV4(), structHash);
                }
            }
            
            
            // File @1inch/limit-order-protocol/contracts/libraries/[email protected]
            
            
            pragma solidity 0.8.17;
            
            library Errors {
                error InvalidMsgValue();
                error ETHTransferFailed();
            }
            
            
            // File @1inch/limit-order-protocol/contracts/helpers/[email protected]
            
            
            pragma solidity 0.8.17;
            
            /// @title A helper contract for calculations related to order amounts
            library AmountCalculator {
                /// @notice Calculates maker amount
                /// @return Result Floored maker amount
                function getMakingAmount(uint256 orderMakerAmount, uint256 orderTakerAmount, uint256 swapTakerAmount) internal pure returns(uint256) {
                    return swapTakerAmount * orderMakerAmount / orderTakerAmount;
                }
            
                /// @notice Calculates taker amount
                /// @return Result Ceiled taker amount
                function getTakingAmount(uint256 orderMakerAmount, uint256 orderTakerAmount, uint256 swapMakerAmount) internal pure returns(uint256) {
                    return (swapMakerAmount * orderTakerAmount + orderMakerAmount - 1) / orderMakerAmount;
                }
            }
            
            
            // File @1inch/limit-order-protocol/contracts/[email protected]
            
            
            pragma solidity 0.8.17;
            
            
            
            
            
            
            
            /// @title RFQ Limit Order mixin
            abstract contract OrderRFQMixin is EIP712, OnlyWethReceiver {
                using SafeERC20 for IERC20;
                using OrderRFQLib for OrderRFQLib.OrderRFQ;
            
                error RFQZeroTargetIsForbidden();
                error RFQPrivateOrder();
                error RFQBadSignature();
                error OrderExpired();
                error MakingAmountExceeded();
                error TakingAmountExceeded();
                error RFQSwapWithZeroAmount();
                error InvalidatedOrder();
            
                /**
                 * @notice Emitted when RFQ gets filled
                 * @param orderHash Hash of the order
                 * @param makingAmount Amount of the maker asset that was transferred from maker to taker
                 */
                event OrderFilledRFQ(
                    bytes32 orderHash,
                    uint256 makingAmount
                );
            
                uint256 private constant _RAW_CALL_GAS_LIMIT = 5000;
                uint256 private constant _MAKER_AMOUNT_FLAG = 1 << 255;
                uint256 private constant _SIGNER_SMART_CONTRACT_HINT = 1 << 254;
                uint256 private constant _IS_VALID_SIGNATURE_65_BYTES = 1 << 253;
                uint256 private constant _UNWRAP_WETH_FLAG = 1 << 252;
                uint256 private constant _AMOUNT_MASK = ~(
                    _MAKER_AMOUNT_FLAG |
                    _SIGNER_SMART_CONTRACT_HINT |
                    _IS_VALID_SIGNATURE_65_BYTES |
                    _UNWRAP_WETH_FLAG
                );
            
                IWETH private immutable _WETH;  // solhint-disable-line var-name-mixedcase
                mapping(address => mapping(uint256 => uint256)) private _invalidator;
            
                constructor(IWETH weth) OnlyWethReceiver(address(weth)) {
                    _WETH = weth;
                }
            
                /**
                 * @notice Returns bitmask for double-spend invalidators based on lowest byte of order.info and filled quotes
                 * @param maker Maker address
                 * @param slot Slot number to return bitmask for
                 * @return result Each bit represents whether corresponding was already invalidated
                 */
                function invalidatorForOrderRFQ(address maker, uint256 slot) external view returns(uint256 /* result */) {
                    return _invalidator[maker][slot];
                }
            
                /**
                 * @notice Cancels order's quote
                 * @param orderInfo Order info (only order id in lowest 64 bits is used)
                 */
                function cancelOrderRFQ(uint256 orderInfo) external {
                    _invalidateOrder(msg.sender, orderInfo, 0);
                }
            
                /// @notice Cancels multiple order's quotes
                function cancelOrderRFQ(uint256 orderInfo, uint256 additionalMask) external {
                    _invalidateOrder(msg.sender, orderInfo, additionalMask);
                }
            
                /**
                 * @notice Fills order's quote, fully or partially (whichever is possible)
                 * @param order Order quote to fill
                 * @param signature Signature to confirm quote ownership
                 * @param flagsAndAmount Fill configuration flags with amount packed in one slot
                 * @return filledMakingAmount Actual amount transferred from maker to taker
                 * @return filledTakingAmount Actual amount transferred from taker to maker
                 * @return orderHash Hash of the filled order
                 */
                function fillOrderRFQ(
                    OrderRFQLib.OrderRFQ memory order,
                    bytes calldata signature,
                    uint256 flagsAndAmount
                ) external payable returns(uint256 /* filledMakingAmount */, uint256 /* filledTakingAmount */, bytes32 /* orderHash */) {
                    return fillOrderRFQTo(order, signature, flagsAndAmount, msg.sender);
                }
            
                /**
                 * @notice Fills order's quote, fully or partially, with compact signature
                 * @param order Order quote to fill
                 * @param r R component of signature
                 * @param vs VS component of signature
                 * @param flagsAndAmount Fill configuration flags with amount packed in one slot
                 * - Bits 0-252 contain the amount to fill
                 * - Bit 253 is used to indicate whether signature is 64-bit (0) or 65-bit (1)
                 * - Bit 254 is used to indicate whether smart contract (1) signed the order or not (0)
                 * - Bit 255 is used to indicate whether maker (1) or taker amount (0) is given in the amount parameter
                 * @return filledMakingAmount Actual amount transferred from maker to taker
                 * @return filledTakingAmount Actual amount transferred from taker to maker
                 * @return orderHash Hash of the filled order
                 */
                function fillOrderRFQCompact(
                    OrderRFQLib.OrderRFQ memory order,
                    bytes32 r,
                    bytes32 vs,
                    uint256 flagsAndAmount
                ) external payable returns(uint256 filledMakingAmount, uint256 filledTakingAmount, bytes32 orderHash) {
                    orderHash = order.hash(_domainSeparatorV4());
                    if (flagsAndAmount & _SIGNER_SMART_CONTRACT_HINT != 0) {
                        if (flagsAndAmount & _IS_VALID_SIGNATURE_65_BYTES != 0) {
                            if (!ECDSA.isValidSignature65(order.maker, orderHash, r, vs)) revert RFQBadSignature();
                        } else {
                            if (!ECDSA.isValidSignature(order.maker, orderHash, r, vs)) revert RFQBadSignature();
                        }
                    } else {
                        if(!ECDSA.recoverOrIsValidSignature(order.maker, orderHash, r, vs)) revert RFQBadSignature();
                    }
            
                    (filledMakingAmount, filledTakingAmount) = _fillOrderRFQTo(order, flagsAndAmount, msg.sender);
                    emit OrderFilledRFQ(orderHash, filledMakingAmount);
                }
            
                /**
                 * @notice Same as `fillOrderRFQTo` but calls permit first.
                 * It allows to approve token spending and make a swap in one transaction.
                 * Also allows to specify funds destination instead of `msg.sender`
                 * @param order Order quote to fill
                 * @param signature Signature to confirm quote ownership
                 * @param flagsAndAmount Fill configuration flags with amount packed in one slot
                 * @param target Address that will receive swap funds
                 * @param permit Should consist of abiencoded token address and encoded `IERC20Permit.permit` call.
                 * @return filledMakingAmount Actual amount transferred from maker to taker
                 * @return filledTakingAmount Actual amount transferred from taker to maker
                 * @return orderHash Hash of the filled order
                 * @dev See tests for examples
                 */
                function fillOrderRFQToWithPermit(
                    OrderRFQLib.OrderRFQ memory order,
                    bytes calldata signature,
                    uint256 flagsAndAmount,
                    address target,
                    bytes calldata permit
                ) external returns(uint256 /* filledMakingAmount */, uint256 /* filledTakingAmount */, bytes32 /* orderHash */) {
                    IERC20(order.takerAsset).safePermit(permit);
                    return fillOrderRFQTo(order, signature, flagsAndAmount, target);
                }
            
                /**
                 * @notice Same as `fillOrderRFQ` but allows to specify funds destination instead of `msg.sender`
                 * @param order Order quote to fill
                 * @param signature Signature to confirm quote ownership
                 * @param flagsAndAmount Fill configuration flags with amount packed in one slot
                 * @param target Address that will receive swap funds
                 * @return filledMakingAmount Actual amount transferred from maker to taker
                 * @return filledTakingAmount Actual amount transferred from taker to maker
                 * @return orderHash Hash of the filled order
                 */
                function fillOrderRFQTo(
                    OrderRFQLib.OrderRFQ memory order,
                    bytes calldata signature,
                    uint256 flagsAndAmount,
                    address target
                ) public payable returns(uint256 filledMakingAmount, uint256 filledTakingAmount, bytes32 orderHash) {
                    orderHash = order.hash(_domainSeparatorV4());
                    if (flagsAndAmount & _SIGNER_SMART_CONTRACT_HINT != 0) {
                        if (flagsAndAmount & _IS_VALID_SIGNATURE_65_BYTES != 0 && signature.length != 65) revert RFQBadSignature();
                        if (!ECDSA.isValidSignature(order.maker, orderHash, signature)) revert RFQBadSignature();
                    } else {
                        if(!ECDSA.recoverOrIsValidSignature(order.maker, orderHash, signature)) revert RFQBadSignature();
                    }
                    (filledMakingAmount, filledTakingAmount) = _fillOrderRFQTo(order, flagsAndAmount, target);
                    emit OrderFilledRFQ(orderHash, filledMakingAmount);
                }
            
                function _fillOrderRFQTo(
                    OrderRFQLib.OrderRFQ memory order,
                    uint256 flagsAndAmount,
                    address target
                ) private returns(uint256 makingAmount, uint256 takingAmount) {
                    if (target == address(0)) revert RFQZeroTargetIsForbidden();
            
                    address maker = order.maker;
            
                    // Validate order
                    if (order.allowedSender != address(0) && order.allowedSender != msg.sender) revert RFQPrivateOrder();
            
                    {  // Stack too deep
                        uint256 info = order.info;
                        // Check time expiration
                        uint256 expiration = uint128(info) >> 64;
                        if (expiration != 0 && block.timestamp > expiration) revert OrderExpired(); // solhint-disable-line not-rely-on-time
                        _invalidateOrder(maker, info, 0);
                    }
            
                    {  // Stack too deep
                        uint256 orderMakingAmount = order.makingAmount;
                        uint256 orderTakingAmount = order.takingAmount;
                        uint256 amount = flagsAndAmount & _AMOUNT_MASK;
                        // Compute partial fill if needed
                        if (amount == 0) {
                            // zero amount means whole order
                            makingAmount = orderMakingAmount;
                            takingAmount = orderTakingAmount;
                        }
                        else if (flagsAndAmount & _MAKER_AMOUNT_FLAG != 0) {
                            if (amount > orderMakingAmount) revert MakingAmountExceeded();
                            makingAmount = amount;
                            takingAmount = AmountCalculator.getTakingAmount(orderMakingAmount, orderTakingAmount, makingAmount);
                        }
                        else {
                            if (amount > orderTakingAmount) revert TakingAmountExceeded();
                            takingAmount = amount;
                            makingAmount = AmountCalculator.getMakingAmount(orderMakingAmount, orderTakingAmount, takingAmount);
                        }
                    }
            
                    if (makingAmount == 0 || takingAmount == 0) revert RFQSwapWithZeroAmount();
            
                    // Maker => Taker
                    if (order.makerAsset == address(_WETH) && flagsAndAmount & _UNWRAP_WETH_FLAG != 0) {
                        _WETH.transferFrom(maker, address(this), makingAmount);
                        _WETH.withdraw(makingAmount);
                        // solhint-disable-next-line avoid-low-level-calls
                        (bool success, ) = target.call{value: makingAmount, gas: _RAW_CALL_GAS_LIMIT}("");
                        if (!success) revert Errors.ETHTransferFailed();
                    } else {
                        IERC20(order.makerAsset).safeTransferFrom(maker, target, makingAmount);
                    }
            
                    // Taker => Maker
                    if (order.takerAsset == address(_WETH) && msg.value > 0) {
                        if (msg.value != takingAmount) revert Errors.InvalidMsgValue();
                        _WETH.deposit{ value: takingAmount }();
                        _WETH.transfer(maker, takingAmount);
                    } else {
                        if (msg.value != 0) revert Errors.InvalidMsgValue();
                        IERC20(order.takerAsset).safeTransferFrom(msg.sender, maker, takingAmount);
                    }
                }
            
                function _invalidateOrder(address maker, uint256 orderInfo, uint256 additionalMask) private {
                    uint256 invalidatorSlot = uint64(orderInfo) >> 8;
                    uint256 invalidatorBits = (1 << uint8(orderInfo)) | additionalMask;
                    mapping(uint256 => uint256) storage invalidatorStorage = _invalidator[maker];
                    uint256 invalidator = invalidatorStorage[invalidatorSlot];
                    if (invalidator & invalidatorBits == invalidatorBits) revert InvalidatedOrder();
                    invalidatorStorage[invalidatorSlot] = invalidator | invalidatorBits;
                }
            }
            
            
            // File @1inch/limit-order-protocol/contracts/[email protected]
            
            
            pragma solidity 0.8.17;
            
            library OrderLib {
                struct Order {
                    uint256 salt;
                    address makerAsset;
                    address takerAsset;
                    address maker;
                    address receiver;
                    address allowedSender;  // equals to Zero address on public orders
                    uint256 makingAmount;
                    uint256 takingAmount;
                    uint256 offsets;
                    // bytes makerAssetData;
                    // bytes takerAssetData;
                    // bytes getMakingAmount; // this.staticcall(abi.encodePacked(bytes, swapTakerAmount)) => (swapMakerAmount)
                    // bytes getTakingAmount; // this.staticcall(abi.encodePacked(bytes, swapMakerAmount)) => (swapTakerAmount)
                    // bytes predicate;       // this.staticcall(bytes) => (bool)
                    // bytes permit;          // On first fill: permit.1.call(abi.encodePacked(permit.selector, permit.2))
                    // bytes preInteraction;
                    // bytes postInteraction;
                    bytes interactions; // concat(makerAssetData, takerAssetData, getMakingAmount, getTakingAmount, predicate, permit, preIntercation, postInteraction)
                }
            
                bytes32 constant internal _LIMIT_ORDER_TYPEHASH = keccak256(
                    "Order("
                        "uint256 salt,"
                        "address makerAsset,"
                        "address takerAsset,"
                        "address maker,"
                        "address receiver,"
                        "address allowedSender,"
                        "uint256 makingAmount,"
                        "uint256 takingAmount,"
                        "uint256 offsets,"
                        "bytes interactions"
                    ")"
                );
            
                enum DynamicField {
                    MakerAssetData,
                    TakerAssetData,
                    GetMakingAmount,
                    GetTakingAmount,
                    Predicate,
                    Permit,
                    PreInteraction,
                    PostInteraction
                }
            
                function getterIsFrozen(bytes calldata getter) internal pure returns(bool) {
                    return getter.length == 1 && getter[0] == "x";
                }
            
                function _get(Order calldata order, DynamicField field) private pure returns(bytes calldata) {
                    uint256 bitShift = uint256(field) << 5; // field * 32
                    return order.interactions[
                        uint32((order.offsets << 32) >> bitShift):
                        uint32(order.offsets >> bitShift)
                    ];
                }
            
                function makerAssetData(Order calldata order) internal pure returns(bytes calldata) {
                    return _get(order, DynamicField.MakerAssetData);
                }
            
                function takerAssetData(Order calldata order) internal pure returns(bytes calldata) {
                    return _get(order, DynamicField.TakerAssetData);
                }
            
                function getMakingAmount(Order calldata order) internal pure returns(bytes calldata) {
                    return _get(order, DynamicField.GetMakingAmount);
                }
            
                function getTakingAmount(Order calldata order) internal pure returns(bytes calldata) {
                    return _get(order, DynamicField.GetTakingAmount);
                }
            
                function predicate(Order calldata order) internal pure returns(bytes calldata) {
                    return _get(order, DynamicField.Predicate);
                }
            
                function permit(Order calldata order) internal pure returns(bytes calldata) {
                    return _get(order, DynamicField.Permit);
                }
            
                function preInteraction(Order calldata order) internal pure returns(bytes calldata) {
                    return _get(order, DynamicField.PreInteraction);
                }
            
                function postInteraction(Order calldata order) internal pure returns(bytes calldata) {
                    return _get(order, DynamicField.PostInteraction);
                }
            
                function hash(Order calldata order, bytes32 domainSeparator) internal pure returns(bytes32 result) {
                    bytes calldata interactions = order.interactions;
                    bytes32 typehash = _LIMIT_ORDER_TYPEHASH;
                    /// @solidity memory-safe-assembly
                    assembly { // solhint-disable-line no-inline-assembly
                        let ptr := mload(0x40)
            
                        // keccak256(abi.encode(_LIMIT_ORDER_TYPEHASH, orderWithoutInteractions, keccak256(order.interactions)));
                        calldatacopy(ptr, interactions.offset, interactions.length)
                        mstore(add(ptr, 0x140), keccak256(ptr, interactions.length))
                        calldatacopy(add(ptr, 0x20), order, 0x120)
                        mstore(ptr, typehash)
                        result := keccak256(ptr, 0x160)
                    }
                    result = ECDSA.toTypedDataHash(domainSeparator, result);
                }
            }
            
            
            // File @1inch/limit-order-protocol/contracts/libraries/[email protected]
            
            
            pragma solidity 0.8.17;
            
            /// @title Library with gas efficient alternatives to `abi.decode`
            library ArgumentsDecoder {
                error IncorrectDataLength();
            
                function decodeUint256(bytes calldata data, uint256 offset) internal pure returns(uint256 value) {
                    unchecked { if (data.length < offset + 32) revert IncorrectDataLength(); }
                    // no memory ops inside so this insertion is automatically memory safe
                    assembly { // solhint-disable-line no-inline-assembly
                        value := calldataload(add(data.offset, offset))
                    }
                }
            
                function decodeSelector(bytes calldata data) internal pure returns(bytes4 value) {
                    if (data.length < 4) revert IncorrectDataLength();
                    // no memory ops inside so this insertion is automatically memory safe
                    assembly { // solhint-disable-line no-inline-assembly
                        value := calldataload(data.offset)
                    }
                }
            
                function decodeTailCalldata(bytes calldata data, uint256 tailOffset) internal pure returns(bytes calldata args) {
                    if (data.length < tailOffset) revert IncorrectDataLength();
                    // no memory ops inside so this insertion is automatically memory safe
                    assembly {  // solhint-disable-line no-inline-assembly
                        args.offset := add(data.offset, tailOffset)
                        args.length := sub(data.length, tailOffset)
                    }
                }
            
                function decodeTargetAndCalldata(bytes calldata data) internal pure returns(address target, bytes calldata args) {
                    if (data.length < 20) revert IncorrectDataLength();
                    // no memory ops inside so this insertion is automatically memory safe
                    assembly {  // solhint-disable-line no-inline-assembly
                        target := shr(96, calldataload(data.offset))
                        args.offset := add(data.offset, 20)
                        args.length := sub(data.length, 20)
                    }
                }
            }
            
            
            // File @1inch/limit-order-protocol/contracts/helpers/[email protected]
            
            
            pragma solidity 0.8.17;
            
            /// @title A helper contract for managing nonce of tx sender
            contract NonceManager {
                error AdvanceNonceFailed();
                event NonceIncreased(address indexed maker, uint256 newNonce);
            
                mapping(address => uint256) public nonce;
            
                /// @notice Advances nonce by one
                function increaseNonce() external {
                    advanceNonce(1);
                }
            
                /// @notice Advances nonce by specified amount
                function advanceNonce(uint8 amount) public {
                    if (amount == 0) revert AdvanceNonceFailed();
                    uint256 newNonce = nonce[msg.sender] + amount;
                    nonce[msg.sender] = newNonce;
                    emit NonceIncreased(msg.sender, newNonce);
                }
            
                /// @notice Checks if `makerAddress` has specified `makerNonce`
                /// @return Result True if `makerAddress` has specified nonce. Otherwise, false
                function nonceEquals(address makerAddress, uint256 makerNonce) public view returns(bool) {
                    return nonce[makerAddress] == makerNonce;
                }
            }
            
            
            // File @1inch/limit-order-protocol/contracts/helpers/[email protected]
            
            
            pragma solidity 0.8.17;
            
            
            /// @title A helper contract for executing boolean functions on arbitrary target call results
            contract PredicateHelper is NonceManager {
                using ArgumentsDecoder for bytes;
            
                error ArbitraryStaticCallFailed();
            
                /// @notice Calls every target with corresponding data
                /// @return Result True if call to any target returned True. Otherwise, false
                function or(uint256 offsets, bytes calldata data) public view returns(bool) {
                    uint256 current;
                    uint256 previous;
                    for (uint256 i = 0; (current = uint32(offsets >> i)) != 0; i += 32) {
                        (bool success, uint256 res) = _selfStaticCall(data[previous:current]);
                        if (success && res == 1) {
                            return true;
                        }
                        previous = current;
                    }
                    return false;
                }
            
                /// @notice Calls every target with corresponding data
                /// @return Result True if calls to all targets returned True. Otherwise, false
                function and(uint256 offsets, bytes calldata data) public view returns(bool) {
                    uint256 current;
                    uint256 previous;
                    for (uint256 i = 0; (current = uint32(offsets >> i)) != 0; i += 32) {
                        (bool success, uint256 res) = _selfStaticCall(data[previous:current]);
                        if (!success || res != 1) {
                            return false;
                        }
                        previous = current;
                    }
                    return true;
                }
            
                /// @notice Calls target with specified data and tests if it's equal to the value
                /// @param value Value to test
                /// @return Result True if call to target returns the same value as `value`. Otherwise, false
                function eq(uint256 value, bytes calldata data) public view returns(bool) {
                    (bool success, uint256 res) = _selfStaticCall(data);
                    return success && res == value;
                }
            
                /// @notice Calls target with specified data and tests if it's lower than value
                /// @param value Value to test
                /// @return Result True if call to target returns value which is lower than `value`. Otherwise, false
                function lt(uint256 value, bytes calldata data) public view returns(bool) {
                    (bool success, uint256 res) = _selfStaticCall(data);
                    return success && res < value;
                }
            
                /// @notice Calls target with specified data and tests if it's bigger than value
                /// @param value Value to test
                /// @return Result True if call to target returns value which is bigger than `value`. Otherwise, false
                function gt(uint256 value, bytes calldata data) public view returns(bool) {
                    (bool success, uint256 res) = _selfStaticCall(data);
                    return success && res > value;
                }
            
                /// @notice Checks passed time against block timestamp
                /// @return Result True if current block timestamp is lower than `time`. Otherwise, false
                function timestampBelow(uint256 time) public view returns(bool) {
                    return block.timestamp < time;  // solhint-disable-line not-rely-on-time
                }
            
                /// @notice Performs an arbitrary call to target with data
                /// @return Result Bytes transmuted to uint256
                function arbitraryStaticCall(address target, bytes calldata data) public view returns(uint256) {
                    (bool success, uint256 res) = _staticcallForUint(target, data);
                    if (!success) revert ArbitraryStaticCallFailed();
                    return res;
                }
            
                function timestampBelowAndNonceEquals(uint256 timeNonceAccount) public view returns(bool) {
                    uint256 _time = uint48(timeNonceAccount >> 208);
                    uint256 _nonce = uint48(timeNonceAccount >> 160);
                    address _account = address(uint160(timeNonceAccount));
                    return timestampBelow(_time) && nonceEquals(_account, _nonce);
                }
            
                function _selfStaticCall(bytes calldata data) internal view returns(bool, uint256) {
                    uint256 selector = uint32(data.decodeSelector());
                    uint256 arg = data.decodeUint256(4);
            
                    // special case for the most often used predicate
                    if (selector == uint32(this.timestampBelowAndNonceEquals.selector)) {  // 0x2cc2878d
                        return (true, timestampBelowAndNonceEquals(arg) ? 1 : 0);
                    }
            
                    if (selector < uint32(this.arbitraryStaticCall.selector)) {  // 0xbf15fcd8
                        if (selector < uint32(this.eq.selector)) {  // 0x6fe7b0ba
                            if (selector == uint32(this.gt.selector)) {  // 0x4f38e2b8
                                return (true, gt(arg, data.decodeTailCalldata(100)) ? 1 : 0);
                            } else if (selector == uint32(this.timestampBelow.selector)) {  // 0x63592c2b
                                return (true, timestampBelow(arg) ? 1 : 0);
                            }
                        } else {
                            if (selector == uint32(this.eq.selector)) {  // 0x6fe7b0ba
                                return (true, eq(arg, data.decodeTailCalldata(100)) ? 1 : 0);
                            } else if (selector == uint32(this.or.selector)) {  // 0x74261145
                                return (true, or(arg, data.decodeTailCalldata(100)) ? 1 : 0);
                            }
                        }
                    } else {
                        if (selector < uint32(this.lt.selector)) {  // 0xca4ece22
                            if (selector == uint32(this.arbitraryStaticCall.selector)) {  // 0xbf15fcd8
                                return (true, arbitraryStaticCall(address(uint160(arg)), data.decodeTailCalldata(100)));
                            } else if (selector == uint32(this.and.selector)) {  // 0xbfa75143
                                return (true, and(arg, data.decodeTailCalldata(100)) ? 1 : 0);
                            }
                        } else {
                            if (selector == uint32(this.lt.selector)) {  // 0xca4ece22
                                return (true, lt(arg, data.decodeTailCalldata(100)) ? 1 : 0);
                            } else if (selector == uint32(this.nonceEquals.selector)) {  // 0xcf6fc6e3
                                return (true, nonceEquals(address(uint160(arg)), data.decodeUint256(0x24)) ? 1 : 0);
                            }
                        }
                    }
            
                    return _staticcallForUint(address(this), data);
                }
            
                function _staticcallForUint(address target, bytes calldata input) private view returns(bool success, uint256 res) {
                    /// @solidity memory-safe-assembly
                    assembly { // solhint-disable-line no-inline-assembly
                        let data := mload(0x40)
            
                        calldatacopy(data, input.offset, input.length)
                        success := staticcall(gas(), target, data, input.length, 0x0, 0x20)
                        success := and(success, eq(returndatasize(), 32))
                        if success {
                            res := mload(0)
                        }
                    }
                }
            }
            
            
            // File @1inch/limit-order-protocol/contracts/interfaces/[email protected]
            
            
            pragma solidity 0.8.17;
            
            interface IOrderMixin {
                /**
                 * @notice Returns unfilled amount for order. Throws if order does not exist
                 * @param orderHash Order's hash. Can be obtained by the `hashOrder` function
                 * @return amount Unfilled amount
                 */
                function remaining(bytes32 orderHash) external view returns(uint256 amount);
            
                /**
                 * @notice Returns unfilled amount for order
                 * @param orderHash Order's hash. Can be obtained by the `hashOrder` function
                 * @return rawAmount Unfilled amount of order plus one if order exists. Otherwise 0
                 */
                function remainingRaw(bytes32 orderHash) external view returns(uint256 rawAmount);
            
                /**
                 * @notice Same as `remainingRaw` but for multiple orders
                 * @param orderHashes Array of hashes
                 * @return rawAmounts Array of amounts for each order plus one if order exists or 0 otherwise
                 */
                function remainingsRaw(bytes32[] memory orderHashes) external view returns(uint256[] memory rawAmounts);
            
                /**
                 * @notice Checks order predicate
                 * @param order Order to check predicate for
                 * @return result Predicate evaluation result. True if predicate allows to fill the order, false otherwise
                 */
                function checkPredicate(OrderLib.Order calldata order) external view returns(bool result);
            
                /**
                 * @notice Returns order hash according to EIP712 standard
                 * @param order Order to get hash for
                 * @return orderHash Hash of the order
                 */
                function hashOrder(OrderLib.Order calldata order) external view returns(bytes32);
            
                /**
                 * @notice Delegates execution to custom implementation. Could be used to validate if `transferFrom` works properly
                 * @dev The function always reverts and returns the simulation results in revert data.
                 * @param target Addresses that will be delegated
                 * @param data Data that will be passed to delegatee
                 */
                function simulate(address target, bytes calldata data) external;
            
                /**
                 * @notice Cancels order.
                 * @dev Order is cancelled by setting remaining amount to _ORDER_FILLED value
                 * @param order Order quote to cancel
                 * @return orderRemaining Unfilled amount of order before cancellation
                 * @return orderHash Hash of the filled order
                 */
                function cancelOrder(OrderLib.Order calldata order) external returns(uint256 orderRemaining, bytes32 orderHash);
            
                /**
                 * @notice Fills an order. If one doesn't exist (first fill) it will be created using order.makerAssetData
                 * @param order Order quote to fill
                 * @param signature Signature to confirm quote ownership
                 * @param interaction A call data for InteractiveNotificationReceiver. Taker may execute interaction after getting maker assets and before sending taker assets.
                 * @param makingAmount Making amount
                 * @param takingAmount Taking amount
                 * @param skipPermitAndThresholdAmount Specifies maximum allowed takingAmount when takingAmount is zero, otherwise specifies minimum allowed makingAmount. Top-most bit specifies whether taker wants to skip maker's permit.
                 * @return actualMakingAmount Actual amount transferred from maker to taker
                 * @return actualTakingAmount Actual amount transferred from taker to maker
                 * @return orderHash Hash of the filled order
                 */
                function fillOrder(
                    OrderLib.Order calldata order,
                    bytes calldata signature,
                    bytes calldata interaction,
                    uint256 makingAmount,
                    uint256 takingAmount,
                    uint256 skipPermitAndThresholdAmount
                ) external payable returns(uint256 actualMakingAmount, uint256 actualTakingAmount, bytes32 orderHash);
            
                /**
                 * @notice Same as `fillOrderTo` but calls permit first,
                 * allowing to approve token spending and make a swap in one transaction.
                 * Also allows to specify funds destination instead of `msg.sender`
                 * @dev See tests for examples
                 * @param order Order quote to fill
                 * @param signature Signature to confirm quote ownership
                 * @param interaction A call data for InteractiveNotificationReceiver. Taker may execute interaction after getting maker assets and before sending taker assets.
                 * @param makingAmount Making amount
                 * @param takingAmount Taking amount
                 * @param skipPermitAndThresholdAmount Specifies maximum allowed takingAmount when takingAmount is zero, otherwise specifies minimum allowed makingAmount. Top-most bit specifies whether taker wants to skip maker's permit.
                 * @param target Address that will receive swap funds
                 * @param permit Should consist of abiencoded token address and encoded `IERC20Permit.permit` call.
                 * @return actualMakingAmount Actual amount transferred from maker to taker
                 * @return actualTakingAmount Actual amount transferred from taker to maker
                 * @return orderHash Hash of the filled order
                 */
                function fillOrderToWithPermit(
                    OrderLib.Order calldata order,
                    bytes calldata signature,
                    bytes calldata interaction,
                    uint256 makingAmount,
                    uint256 takingAmount,
                    uint256 skipPermitAndThresholdAmount,
                    address target,
                    bytes calldata permit
                ) external returns(uint256 actualMakingAmount, uint256 actualTakingAmount, bytes32 orderHash);
            
                /**
                 * @notice Same as `fillOrder` but allows to specify funds destination instead of `msg.sender`
                 * @param order_ Order quote to fill
                 * @param signature Signature to confirm quote ownership
                 * @param interaction A call data for InteractiveNotificationReceiver. Taker may execute interaction after getting maker assets and before sending taker assets.
                 * @param makingAmount Making amount
                 * @param takingAmount Taking amount
                 * @param skipPermitAndThresholdAmount Specifies maximum allowed takingAmount when takingAmount is zero, otherwise specifies minimum allowed makingAmount. Top-most bit specifies whether taker wants to skip maker's permit.
                 * @param target Address that will receive swap funds
                 * @return actualMakingAmount Actual amount transferred from maker to taker
                 * @return actualTakingAmount Actual amount transferred from taker to maker
                 * @return orderHash Hash of the filled order
                 */
                function fillOrderTo(
                    OrderLib.Order calldata order_,
                    bytes calldata signature,
                    bytes calldata interaction,
                    uint256 makingAmount,
                    uint256 takingAmount,
                    uint256 skipPermitAndThresholdAmount,
                    address target
                ) external payable returns(uint256 actualMakingAmount, uint256 actualTakingAmount, bytes32 orderHash);
            }
            
            
            // File @1inch/limit-order-protocol/contracts/interfaces/[email protected]
            
            
            pragma solidity 0.8.17;
            
            /// @title Interface for interactor which acts between `maker => taker` and `taker => maker` transfers.
            interface PreInteractionNotificationReceiver {
                function fillOrderPreInteraction(
                    bytes32 orderHash,
                    address maker,
                    address taker,
                    uint256 makingAmount,
                    uint256 takingAmount,
                    uint256 remainingAmount,
                    bytes memory interactiveData
                ) external;
            }
            
            interface PostInteractionNotificationReceiver {
                /// @notice Callback method that gets called after taker transferred funds to maker but before
                /// the opposite transfer happened
                function fillOrderPostInteraction(
                    bytes32 orderHash,
                    address maker,
                    address taker,
                    uint256 makingAmount,
                    uint256 takingAmount,
                    uint256 remainingAmount,
                    bytes memory interactiveData
                ) external;
            }
            
            interface InteractionNotificationReceiver {
                function fillOrderInteraction(
                    address taker,
                    uint256 makingAmount,
                    uint256 takingAmount,
                    bytes memory interactiveData
                ) external returns(uint256 offeredTakingAmount);
            }
            
            
            // File @1inch/limit-order-protocol/contracts/[email protected]
            
            
            pragma solidity 0.8.17;
            
            
            
            
            
            
            
            
            
            
            
            /// @title Regular Limit Order mixin
            abstract contract OrderMixin is IOrderMixin, EIP712, PredicateHelper {
                using SafeERC20 for IERC20;
                using ArgumentsDecoder for bytes;
                using OrderLib for OrderLib.Order;
            
                error UnknownOrder();
                error AccessDenied();
                error AlreadyFilled();
                error PermitLengthTooLow();
                error ZeroTargetIsForbidden();
                error RemainingAmountIsZero();
                error PrivateOrder();
                error BadSignature();
                error ReentrancyDetected();
                error PredicateIsNotTrue();
                error OnlyOneAmountShouldBeZero();
                error TakingAmountTooHigh();
                error MakingAmountTooLow();
                error SwapWithZeroAmount();
                error TransferFromMakerToTakerFailed();
                error TransferFromTakerToMakerFailed();
                error WrongAmount();
                error WrongGetter();
                error GetAmountCallFailed();
                error TakingAmountIncreased();
                error SimulationResults(bool success, bytes res);
            
                /// @notice Emitted every time order gets filled, including partial fills
                event OrderFilled(
                    address indexed maker,
                    bytes32 orderHash,
                    uint256 remaining
                );
            
                /// @notice Emitted when order gets cancelled
                event OrderCanceled(
                    address indexed maker,
                    bytes32 orderHash,
                    uint256 remainingRaw
                );
            
                uint256 constant private _ORDER_DOES_NOT_EXIST = 0;
                uint256 constant private _ORDER_FILLED = 1;
                uint256 constant private _SKIP_PERMIT_FLAG = 1 << 255;
                uint256 constant private _THRESHOLD_MASK = ~_SKIP_PERMIT_FLAG;
            
                IWETH private immutable _WETH;  // solhint-disable-line var-name-mixedcase
                /// @notice Stores unfilled amounts for each order plus one.
                /// Therefore 0 means order doesn't exist and 1 means order was filled
                mapping(bytes32 => uint256) private _remaining;
            
                constructor(IWETH weth) {
                    _WETH = weth;
                }
            
                /**
                 * @notice See {IOrderMixin-remaining}.
                 */
                function remaining(bytes32 orderHash) external view returns(uint256 /* amount */) {
                    uint256 amount = _remaining[orderHash];
                    if (amount == _ORDER_DOES_NOT_EXIST) revert UnknownOrder();
                    unchecked { return amount - 1; }
                }
            
                /**
                 * @notice See {IOrderMixin-remainingRaw}.
                 */
                function remainingRaw(bytes32 orderHash) external view returns(uint256 /* rawAmount */) {
                    return _remaining[orderHash];
                }
            
                /**
                 * @notice See {IOrderMixin-remainingsRaw}.
                 */
                function remainingsRaw(bytes32[] memory orderHashes) external view returns(uint256[] memory /* rawAmounts */) {
                    uint256[] memory results = new uint256[](orderHashes.length);
                    for (uint256 i = 0; i < orderHashes.length; i++) {
                        results[i] = _remaining[orderHashes[i]];
                    }
                    return results;
                }
            
                /**
                 * @notice See {IOrderMixin-simulate}.
                 */
                function simulate(address target, bytes calldata data) external {
                    // solhint-disable-next-line avoid-low-level-calls
                    (bool success, bytes memory result) = target.delegatecall(data);
                    revert SimulationResults(success, result);
                }
            
                /**
                 * @notice See {IOrderMixin-cancelOrder}.
                 */
                function cancelOrder(OrderLib.Order calldata order) external returns(uint256 orderRemaining, bytes32 orderHash) {
                    if (order.maker != msg.sender) revert AccessDenied();
            
                    orderHash = hashOrder(order);
                    orderRemaining = _remaining[orderHash];
                    if (orderRemaining == _ORDER_FILLED) revert AlreadyFilled();
                    emit OrderCanceled(msg.sender, orderHash, orderRemaining);
                    _remaining[orderHash] = _ORDER_FILLED;
                }
            
                /**
                 * @notice See {IOrderMixin-fillOrder}.
                 */
                function fillOrder(
                    OrderLib.Order calldata order,
                    bytes calldata signature,
                    bytes calldata interaction,
                    uint256 makingAmount,
                    uint256 takingAmount,
                    uint256 skipPermitAndThresholdAmount
                ) external payable returns(uint256 /* actualMakingAmount */, uint256 /* actualTakingAmount */, bytes32 /* orderHash */) {
                    return fillOrderTo(order, signature, interaction, makingAmount, takingAmount, skipPermitAndThresholdAmount, msg.sender);
                }
            
                /**
                 * @notice See {IOrderMixin-fillOrderToWithPermit}.
                 */
                function fillOrderToWithPermit(
                    OrderLib.Order calldata order,
                    bytes calldata signature,
                    bytes calldata interaction,
                    uint256 makingAmount,
                    uint256 takingAmount,
                    uint256 skipPermitAndThresholdAmount,
                    address target,
                    bytes calldata permit
                ) external returns(uint256 /* actualMakingAmount */, uint256 /* actualTakingAmount */, bytes32 /* orderHash */) {
                    if (permit.length < 20) revert PermitLengthTooLow();
                    {  // Stack too deep
                        (address token, bytes calldata permitData) = permit.decodeTargetAndCalldata();
                        IERC20(token).safePermit(permitData);
                    }
                    return fillOrderTo(order, signature, interaction, makingAmount, takingAmount, skipPermitAndThresholdAmount, target);
                }
            
                /**
                 * @notice See {IOrderMixin-fillOrderTo}.
                 */
                function fillOrderTo(
                    OrderLib.Order calldata order_,
                    bytes calldata signature,
                    bytes calldata interaction,
                    uint256 makingAmount,
                    uint256 takingAmount,
                    uint256 skipPermitAndThresholdAmount,
                    address target
                ) public payable returns(uint256 actualMakingAmount, uint256 actualTakingAmount, bytes32 orderHash) {
                    if (target == address(0)) revert ZeroTargetIsForbidden();
                    orderHash = hashOrder(order_);
            
                    OrderLib.Order calldata order = order_; // Helps with "Stack too deep"
                    actualMakingAmount = makingAmount;
                    actualTakingAmount = takingAmount;
            
                    uint256 remainingMakingAmount = _remaining[orderHash];
                    if (remainingMakingAmount == _ORDER_FILLED) revert RemainingAmountIsZero();
                    if (order.allowedSender != address(0) && order.allowedSender != msg.sender) revert PrivateOrder();
                    if (remainingMakingAmount == _ORDER_DOES_NOT_EXIST) {
                        // First fill: validate order and permit maker asset
                        if (!ECDSA.recoverOrIsValidSignature(order.maker, orderHash, signature)) revert BadSignature();
                        remainingMakingAmount = order.makingAmount;
            
                        bytes calldata permit = order.permit();
                        if (skipPermitAndThresholdAmount & _SKIP_PERMIT_FLAG == 0 && permit.length >= 20) {
                            // proceed only if taker is willing to execute permit and its length is enough to store address
                            (address token, bytes calldata permitCalldata) = permit.decodeTargetAndCalldata();
                            IERC20(token).safePermit(permitCalldata);
                            if (_remaining[orderHash] != _ORDER_DOES_NOT_EXIST) revert ReentrancyDetected();
                        }
                    } else {
                        unchecked { remainingMakingAmount -= 1; }
                    }
            
                    // Check if order is valid
                    if (order.predicate().length > 0) {
                        if (!checkPredicate(order)) revert PredicateIsNotTrue();
                    }
            
                    // Compute maker and taker assets amount
                    if ((actualTakingAmount == 0) == (actualMakingAmount == 0)) {
                        revert OnlyOneAmountShouldBeZero();
                    } else if (actualTakingAmount == 0) {
                        if (actualMakingAmount > remainingMakingAmount) {
                            actualMakingAmount = remainingMakingAmount;
                        }
                        actualTakingAmount = _getTakingAmount(order.getTakingAmount(), order.makingAmount, actualMakingAmount, order.takingAmount, remainingMakingAmount, orderHash);
                        uint256 thresholdAmount = skipPermitAndThresholdAmount & _THRESHOLD_MASK;
                        // check that actual rate is not worse than what was expected
                        // actualTakingAmount / actualMakingAmount <= thresholdAmount / makingAmount
                        if (actualTakingAmount * makingAmount > thresholdAmount * actualMakingAmount) revert TakingAmountTooHigh();
                    } else {
                        actualMakingAmount = _getMakingAmount(order.getMakingAmount(), order.takingAmount, actualTakingAmount, order.makingAmount, remainingMakingAmount, orderHash);
                        if (actualMakingAmount > remainingMakingAmount) {
                            actualMakingAmount = remainingMakingAmount;
                            actualTakingAmount = _getTakingAmount(order.getTakingAmount(), order.makingAmount, actualMakingAmount, order.takingAmount, remainingMakingAmount, orderHash);
                            if (actualTakingAmount > takingAmount) revert TakingAmountIncreased();
                        }
                        uint256 thresholdAmount = skipPermitAndThresholdAmount & _THRESHOLD_MASK;
                        // check that actual rate is not worse than what was expected
                        // actualMakingAmount / actualTakingAmount >= thresholdAmount / takingAmount
                        if (actualMakingAmount * takingAmount < thresholdAmount * actualTakingAmount) revert MakingAmountTooLow();
                    }
            
                    if (actualMakingAmount == 0 || actualTakingAmount == 0) revert SwapWithZeroAmount();
            
                    // Update remaining amount in storage
                    unchecked {
                        remainingMakingAmount = remainingMakingAmount - actualMakingAmount;
                        _remaining[orderHash] = remainingMakingAmount + 1;
                    }
                    emit OrderFilled(order_.maker, orderHash, remainingMakingAmount);
            
                    // Maker can handle funds interactively
                    if (order.preInteraction().length >= 20) {
                        // proceed only if interaction length is enough to store address
                        (address interactionTarget, bytes calldata interactionData) = order.preInteraction().decodeTargetAndCalldata();
                        PreInteractionNotificationReceiver(interactionTarget).fillOrderPreInteraction(
                            orderHash, order.maker, msg.sender, actualMakingAmount, actualTakingAmount, remainingMakingAmount, interactionData
                        );
                    }
            
                    // Maker => Taker
                    if (!_callTransferFrom(
                        order.makerAsset,
                        order.maker,
                        target,
                        actualMakingAmount,
                        order.makerAssetData()
                    )) revert TransferFromMakerToTakerFailed();
            
                    if (interaction.length >= 20) {
                        // proceed only if interaction length is enough to store address
                        (address interactionTarget, bytes calldata interactionData) = interaction.decodeTargetAndCalldata();
                        uint256 offeredTakingAmount = InteractionNotificationReceiver(interactionTarget).fillOrderInteraction(
                            msg.sender, actualMakingAmount, actualTakingAmount, interactionData
                        );
            
                        if (offeredTakingAmount > actualTakingAmount &&
                            !OrderLib.getterIsFrozen(order.getMakingAmount()) &&
                            !OrderLib.getterIsFrozen(order.getTakingAmount()))
                        {
                            actualTakingAmount = offeredTakingAmount;
                        }
                    }
            
                    // Taker => Maker
                    if (order.takerAsset == address(_WETH) && msg.value > 0) {
                        if (msg.value < actualTakingAmount) revert Errors.InvalidMsgValue();
                        if (msg.value > actualTakingAmount) {
                            unchecked {
                                (bool success, ) = msg.sender.call{value: msg.value - actualTakingAmount}("");  // solhint-disable-line avoid-low-level-calls
                                if (!success) revert Errors.ETHTransferFailed();
                            }
                        }
                        _WETH.deposit{ value: actualTakingAmount }();
                        _WETH.transfer(order.receiver == address(0) ? order.maker : order.receiver, actualTakingAmount);
                    } else {
                        if (msg.value != 0) revert Errors.InvalidMsgValue();
                        if (!_callTransferFrom(
                            order.takerAsset,
                            msg.sender,
                            order.receiver == address(0) ? order.maker : order.receiver,
                            actualTakingAmount,
                            order.takerAssetData()
                        )) revert TransferFromTakerToMakerFailed();
                    }
            
                    // Maker can handle funds interactively
                    if (order.postInteraction().length >= 20) {
                        // proceed only if interaction length is enough to store address
                        (address interactionTarget, bytes calldata interactionData) = order.postInteraction().decodeTargetAndCalldata();
                        PostInteractionNotificationReceiver(interactionTarget).fillOrderPostInteraction(
                             orderHash, order.maker, msg.sender, actualMakingAmount, actualTakingAmount, remainingMakingAmount, interactionData
                        );
                    }
                }
            
                /**
                 * @notice See {IOrderMixin-checkPredicate}.
                 */
                function checkPredicate(OrderLib.Order calldata order) public view returns(bool) {
                    (bool success, uint256 res) = _selfStaticCall(order.predicate());
                    return success && res == 1;
                }
            
                /**
                 * @notice See {IOrderMixin-hashOrder}.
                 */
                function hashOrder(OrderLib.Order calldata order) public view returns(bytes32) {
                    return order.hash(_domainSeparatorV4());
                }
            
                function _callTransferFrom(address asset, address from, address to, uint256 amount, bytes calldata input) private returns(bool success) {
                    bytes4 selector = IERC20.transferFrom.selector;
                    /// @solidity memory-safe-assembly
                    assembly { // solhint-disable-line no-inline-assembly
                        let data := mload(0x40)
            
                        mstore(data, selector)
                        mstore(add(data, 0x04), from)
                        mstore(add(data, 0x24), to)
                        mstore(add(data, 0x44), amount)
                        calldatacopy(add(data, 0x64), input.offset, input.length)
                        let status := call(gas(), asset, 0, data, add(0x64, input.length), 0x0, 0x20)
                        success := and(status, or(iszero(returndatasize()), and(gt(returndatasize(), 31), eq(mload(0), 1))))
                    }
                }
            
                function _getMakingAmount(
                    bytes calldata getter,
                    uint256 orderTakingAmount,
                    uint256 requestedTakingAmount,
                    uint256 orderMakingAmount,
                    uint256 remainingMakingAmount,
                    bytes32 orderHash
                ) private view returns(uint256) {
                    if (getter.length == 0) {
                        // Linear proportion
                        return AmountCalculator.getMakingAmount(orderMakingAmount, orderTakingAmount, requestedTakingAmount);
                    }
                    return _callGetter(getter, orderTakingAmount, requestedTakingAmount, orderMakingAmount, remainingMakingAmount, orderHash);
                }
            
                function _getTakingAmount(
                    bytes calldata getter,
                    uint256 orderMakingAmount,
                    uint256 requestedMakingAmount,
                    uint256 orderTakingAmount,
                    uint256 remainingMakingAmount,
                    bytes32 orderHash
                ) private view returns(uint256) {
                    if (getter.length == 0) {
                        // Linear proportion
                        return AmountCalculator.getTakingAmount(orderMakingAmount, orderTakingAmount, requestedMakingAmount);
                    }
                    return _callGetter(getter, orderMakingAmount, requestedMakingAmount, orderTakingAmount, remainingMakingAmount, orderHash);
                }
            
                function _callGetter(
                    bytes calldata getter,
                    uint256 orderExpectedAmount,
                    uint256 requestedAmount,
                    uint256 orderResultAmount,
                    uint256 remainingMakingAmount,
                    bytes32 orderHash
                ) private view returns(uint256) {
                    if (getter.length == 1) {
                        if (OrderLib.getterIsFrozen(getter)) {
                            // On "x" getter calldata only exact amount is allowed
                            if (requestedAmount != orderExpectedAmount) revert WrongAmount();
                            return orderResultAmount;
                        } else {
                            revert WrongGetter();
                        }
                    } else {
                        (address target, bytes calldata data) = getter.decodeTargetAndCalldata();
                        (bool success, bytes memory result) = target.staticcall(abi.encodePacked(data, requestedAmount, remainingMakingAmount, orderHash));
                        if (!success || result.length != 32) revert GetAmountCallFailed();
                        return abi.decode(result, (uint256));
                    }
                }
            }
            
            
            // File @openzeppelin/contracts/utils/[email protected]
            
            // OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
            
            pragma solidity ^0.8.0;
            
            /**
             * @dev Provides information about the current execution context, including the
             * sender of the transaction and its data. While these are generally available
             * via msg.sender and msg.data, they should not be accessed in such a direct
             * manner, since when dealing with meta-transactions the account sending and
             * paying for execution may not be the actual sender (as far as an application
             * is concerned).
             *
             * This contract is only required for intermediate, library-like contracts.
             */
            abstract contract Context {
                function _msgSender() internal view virtual returns (address) {
                    return msg.sender;
                }
            
                function _msgData() internal view virtual returns (bytes calldata) {
                    return msg.data;
                }
            }
            
            
            // File @openzeppelin/contracts/access/[email protected]
            
            // OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)
            
            pragma solidity ^0.8.0;
            
            /**
             * @dev Contract module which provides a basic access control mechanism, where
             * there is an account (an owner) that can be granted exclusive access to
             * specific functions.
             *
             * By default, the owner account will be the one that deploys the contract. This
             * can later be changed with {transferOwnership}.
             *
             * This module is used through inheritance. It will make available the modifier
             * `onlyOwner`, which can be applied to your functions to restrict their use to
             * the owner.
             */
            abstract contract Ownable is Context {
                address private _owner;
            
                event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
            
                /**
                 * @dev Initializes the contract setting the deployer as the initial owner.
                 */
                constructor() {
                    _transferOwnership(_msgSender());
                }
            
                /**
                 * @dev Throws if called by any account other than the owner.
                 */
                modifier onlyOwner() {
                    _checkOwner();
                    _;
                }
            
                /**
                 * @dev Returns the address of the current owner.
                 */
                function owner() public view virtual returns (address) {
                    return _owner;
                }
            
                /**
                 * @dev Throws if the sender is not the owner.
                 */
                function _checkOwner() internal view virtual {
                    require(owner() == _msgSender(), "Ownable: caller is not the owner");
                }
            
                /**
                 * @dev Leaves the contract without owner. It will not be possible to call
                 * `onlyOwner` functions anymore. Can only be called by the current owner.
                 *
                 * NOTE: Renouncing ownership will leave the contract without an owner,
                 * thereby removing any functionality that is only available to the owner.
                 */
                function renounceOwnership() public virtual onlyOwner {
                    _transferOwnership(address(0));
                }
            
                /**
                 * @dev Transfers ownership of the contract to a new account (`newOwner`).
                 * Can only be called by the current owner.
                 */
                function transferOwnership(address newOwner) public virtual onlyOwner {
                    require(newOwner != address(0), "Ownable: new owner is the zero address");
                    _transferOwnership(newOwner);
                }
            
                /**
                 * @dev Transfers ownership of the contract to a new account (`newOwner`).
                 * Internal function without access restriction.
                 */
                function _transferOwnership(address newOwner) internal virtual {
                    address oldOwner = _owner;
                    _owner = newOwner;
                    emit OwnershipTransferred(oldOwner, newOwner);
                }
            }
            
            
            // File contracts/AggregationRouterV5.sol
            
            
            pragma solidity 0.8.17;
            
            
            
            
            
            
            
            
            
            /// @notice Main contract incorporates a number of routers to perform swaps and limit orders protocol to fill limit orders
            contract AggregationRouterV5 is EIP712("1inch Aggregation Router", "5"), Ownable,
                ClipperRouter, GenericRouter, UnoswapRouter, UnoswapV3Router, OrderMixin, OrderRFQMixin
            {
                using UniERC20 for IERC20;
            
                error ZeroAddress();
            
                /**
                 * @dev Sets the wrapped eth token and clipper exhange interface
                 * Both values are immutable: they can only be set once during
                 * construction.
                 */
                constructor(IWETH weth)
                    UnoswapV3Router(weth)
                    ClipperRouter(weth)
                    OrderMixin(weth)
                    OrderRFQMixin(weth)
                {
                    if (address(weth) == address(0)) revert ZeroAddress();
                }
            
                /**
                 * @notice Retrieves funds accidently sent directly to the contract address
                 * @param token ERC20 token to retrieve
                 * @param amount amount to retrieve
                 */
                function rescueFunds(IERC20 token, uint256 amount) external onlyOwner {
                    token.uniTransfer(payable(msg.sender), amount);
                }
            
                /**
                 * @notice Destroys the contract and sends eth to sender. Use with caution.
                 * The only case when the use of the method is justified is if there is an exploit found.
                 * And the damage from the exploit is greater than from just an urgent contract change.
                 */
                function destroy() external onlyOwner {
                    selfdestruct(payable(msg.sender));
                }
            
                function _receive() internal override(EthReceiver, OnlyWethReceiver) {
                    EthReceiver._receive();
                }
            }

            File 2 of 5: Elevate
            /**
             *Submitted for verification at Etherscan.io on 2023-03-31
            */
            
            // SPDX-License-Identifier: MIT                                                                               
                                                                
            pragma solidity 0.8.17;
            
            abstract contract Context {
                function _msgSender() internal view virtual returns (address) {
                    return msg.sender;
                }
            
                function _msgData() internal view virtual returns (bytes calldata) {
                    this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
                    return msg.data;
                }
            }
            
            interface IERC20 {
                function totalSupply() external view returns (uint256);
                function balanceOf(address account) external view returns (uint256);
                function transfer(address recipient, uint256 amount) external returns (bool);
                function allowance(address owner, address spender) external view returns (uint256);
                function approve(address spender, uint256 amount) external returns (bool);
                function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
                function name() external view returns (string memory);
                function symbol() external view returns (string memory);
                function decimals() external view returns (uint8);
            
                event Transfer(address indexed from, address indexed to, uint256 value);
                event Approval(address indexed owner, address indexed spender, uint256 value);
            }
            
            contract ERC20 is Context, IERC20 {
                mapping(address => uint256) private _balances;
                mapping(address => mapping(address => uint256)) private _allowances;
                uint256 private _totalSupply;
                string private _name;
                string private _symbol;
            
                constructor(string memory name_, string memory symbol_) {
                    _name = name_;
                    _symbol = symbol_;
                }
            
                function name() public view virtual override returns (string memory) {
                    return _name;
                }
            
                function symbol() public view virtual override returns (string memory) {
                    return _symbol;
                }
            
                function decimals() public view virtual override returns (uint8) {
                    return 18;
                }
            
                function totalSupply() public view virtual override returns (uint256) {
                    return _totalSupply;
                }
            
                function balanceOf(address account) public view virtual override returns (uint256) {
                    return _balances[account];
                }
            
                function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
                    _transfer(_msgSender(), recipient, amount);
                    return true;
                }
            
                function allowance(address owner, address spender) public view virtual override returns (uint256) {
                    return _allowances[owner][spender];
                }
            
                function approve(address spender, uint256 amount) public virtual override returns (bool) {
                    _approve(_msgSender(), spender, amount);
                    return true;
                }
            
                function transferFrom(address sender, address recipient, uint256 amount) public virtual override returns (bool) {
                    _transfer(sender, recipient, amount);
            
                    uint256 currentAllowance = _allowances[sender][_msgSender()];
                    if(currentAllowance != type(uint256).max){
                        require(currentAllowance >= amount, "ERC20: transfer amount exceeds allowance");
                        unchecked {
                            _approve(sender, _msgSender(), currentAllowance - amount);
                        }
                    }
            
                    return true;
                }
            
                function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
                    _approve(_msgSender(), spender, _allowances[_msgSender()][spender] + addedValue);
                    return true;
                }
            
                function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
                    uint256 currentAllowance = _allowances[_msgSender()][spender];
                    require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
                    unchecked {
                        _approve(_msgSender(), spender, currentAllowance - subtractedValue);
                    }
            
                    return true;
                }
            
                function _transfer(address sender, address recipient, uint256 amount) internal virtual {
                    require(sender != address(0), "ERC20: transfer from the zero address");
                    require(recipient != address(0), "ERC20: transfer to the zero address");
            
                    uint256 senderBalance = _balances[sender];
                    require(senderBalance >= amount, "ERC20: transfer amount exceeds balance");
                    unchecked {
                        _balances[sender] = senderBalance - amount;
                    }
                    _balances[recipient] += amount;
            
                    emit Transfer(sender, recipient, amount);
                }
            
                function _createInitialSupply(address account, uint256 amount) internal virtual {
                    require(account != address(0), "ERC20: mint to the zero address");
            
                    _totalSupply += amount;
                    _balances[account] += amount;
                    emit Transfer(address(0), account, amount);
                }
            
                function _approve(address owner, address spender, uint256 amount) internal virtual {
                    require(owner != address(0), "ERC20: approve from the zero address");
                    require(spender != address(0), "ERC20: approve to the zero address");
            
                    _allowances[owner][spender] = amount;
                    emit Approval(owner, spender, amount);
                }
            }
            
            contract Ownable is Context {
                address private _owner;
            
                event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
                
                constructor () {
                    address msgSender = _msgSender();
                    _owner = msgSender;
                    emit OwnershipTransferred(address(0), msgSender);
                }
            
                function owner() public view returns (address) {
                    return _owner;
                }
            
                modifier onlyOwner() {
                    require(_owner == _msgSender(), "Ownable: caller is not the owner");
                    _;
                }
            
                function renounceOwnership() external virtual onlyOwner {
                    emit OwnershipTransferred(_owner, address(0));
                    _owner = address(0);
                }
            
                function transferOwnership(address newOwner) public virtual onlyOwner {
                    require(newOwner != address(0), "Ownable: new owner is the zero address");
                    emit OwnershipTransferred(_owner, newOwner);
                    _owner = newOwner;
                }
            }
            
            interface IDexRouter {
                function factory() external pure returns (address);
                function WETH() external pure returns (address);
                function swapExactTokensForETHSupportingFeeOnTransferTokens(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline) external;
                function swapExactETHForTokensSupportingFeeOnTransferTokens(uint amountOutMin, address[] calldata path, address to, uint deadline) external payable;
                function swapExactTokensForTokensSupportingFeeOnTransferTokens(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline) external;
                function addLiquidityETH(address token, uint256 amountTokenDesired, uint256 amountTokenMin, uint256 amountETHMin, address to, uint256 deadline) external payable returns (uint256 amountToken, uint256 amountETH, uint256 liquidity);
                function addLiquidity(address tokenA, address tokenB, uint amountADesired, uint amountBDesired, uint amountAMin, uint amountBMin, address to, uint deadline) external returns (uint amountA, uint amountB, uint liquidity);
                function getAmountsOut(uint amountIn, address[] calldata path) external view returns (uint[] memory amounts);
            }
            
            interface IDexFactory {
                function createPair(address tokenA, address tokenB) external returns (address pair);
            }
            
            contract Elevate is ERC20, Ownable {
            
                uint256 public maxTxnAmount;
            
                IDexRouter public immutable dexRouter;
                address public immutable lpPairEth;
            
                bool private swapping;
                uint256 public swapTokensAtAmount;
            
                address public impactAddress;
                address public crfAddress;
                address public operationsAddress;
                address public liquidityAddress;
                address public treasuryAddress;
            
                uint256 public tradingActiveBlock = 0; // 0 means trading is not active
                mapping (address => bool) public restrictedWallets;
            
                bool public limitsInEffect = true;
                bool public tradingActive = false;
                bool public swapEnabled = false;
                
                uint256 public buyTotalFees;
                uint256 public buyLiquidityFee;
                uint256 public buyImpactFee;
                uint256 public buyCRFFee;
                uint256 public buyOperationsFee;
                uint256 public buyTreasuryFee;
            
                uint256 public sellTotalFees;
                uint256 public sellImpactFee;
                uint256 public sellLiquidityFee;
                uint256 public sellCRFFee;
                uint256 public sellOperationsFee;
                uint256 public sellTreasuryFee;
            
                uint256 constant FEE_DIVISOR = 10000;
            
                uint256 public tokensForImpact;
                uint256 public tokensForLiquidity;
                uint256 public tokensForCRF;
                uint256 public tokensForOperations;
                uint256 public tokensForTreasury;
                
                mapping (address => bool) private _isExcludedFromFees;
                mapping (address => bool) public _isExcludedMaxTransactionAmount;
            
                mapping (address => bool) public automatedMarketMakerPairs;
            
                // Events
            
                event SetAutomatedMarketMakerPair(address indexed pair, bool indexed value);
                event EnabledTrading();
                event RemovedLimits();
                event ExcludeFromFees(address indexed account, bool isExcluded);
                event UpdatedMaxTxnAmount(uint256 newAmount);
                event UpdatedBuyFee(uint256 newAmount);
                event UpdatedSellFee(uint256 newAmount);
                event UpdatedImpactAddress(address indexed newWallet);
                event UpdatedLiquidityAddress(address indexed newWallet);
                event UpdatedCRFAddress(address indexed newWallet);
                event UpdatedOperationsAddress(address indexed newWallet);
                event UpdatedTreasuryAddress(address indexed newWallet);
                event MaxTransactionExclusion(address _address, bool excluded);
                event OwnerForcedSwapBack(uint256 timestamp);
                event TransferForeignToken(address token, uint256 amount);
            
                constructor() ERC20("Elevate", "ELEV") {
            
                    address _dexRouter;
            
                    // automatically detect router/desired stablecoin
                    if(block.chainid == 1){
                        _dexRouter = 0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D; // ETH: Uniswap V2
                    } else if(block.chainid == 5){
                        _dexRouter = 0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D; // Goerli ETH: Uniswap V2
                    } else if(block.chainid == 97){
                        _dexRouter = 0xD99D1c33F9fC3444f8101754aBC46c52416550D1; // BNB Chain: PCS V2
                    } else {
                        revert("Chain not configured");
                    }
            
                    address newOwner = msg.sender; // can leave alone if owner is deployer.
            
                    dexRouter = IDexRouter(_dexRouter);
            
                    // create pair
            
                    lpPairEth = IDexFactory(dexRouter.factory()).createPair(address(this), dexRouter.WETH());
                    setAutomatedMarketMakerPair(address(lpPairEth), true);
            
                    uint256 totalSupply = 5 * 1e9 * 1e18;
                    
                    maxTxnAmount = totalSupply * 25 / 10000;
                    swapTokensAtAmount = totalSupply * 25 / 100000;
            
                    buyImpactFee = 0;
                    buyLiquidityFee = 100;
                    buyCRFFee = 100;
                    buyOperationsFee = 100;
                    buyTreasuryFee = 100;
                    buyTotalFees = buyImpactFee + buyLiquidityFee + buyCRFFee + buyOperationsFee + buyTreasuryFee;
            
            
                    sellImpactFee = 0;
                    sellLiquidityFee = 100;
                    sellCRFFee = 100;
                    sellOperationsFee = 100;
                    sellTreasuryFee = 100;
                    sellTotalFees = sellImpactFee + sellLiquidityFee + sellCRFFee + sellOperationsFee + sellTreasuryFee;
            
                    // update these!
                    impactAddress = address(newOwner);
                    liquidityAddress = address(newOwner);
                    operationsAddress = address(newOwner);
                    crfAddress = address(newOwner);
                    treasuryAddress = address(newOwner);
            
                    _excludeFromMaxTransaction(newOwner, true);
                    _excludeFromMaxTransaction(address(this), true);
                    _excludeFromMaxTransaction(address(0xdead), true);
                    _excludeFromMaxTransaction(address(impactAddress), true);
                    _excludeFromMaxTransaction(address(liquidityAddress), true);
                    _excludeFromMaxTransaction(address(operationsAddress), true);
                    _excludeFromMaxTransaction(address(crfAddress), true);
                    _excludeFromMaxTransaction(address(dexRouter), true);
            
                    excludeFromFees(newOwner, true);
                    excludeFromFees(address(this), true);
                    excludeFromFees(address(0xdead), true);
                    excludeFromFees(address(impactAddress), true);
                    excludeFromFees(address(liquidityAddress), true);
                    excludeFromFees(address(operationsAddress), true);
                    excludeFromFees(address(crfAddress), true);
                    excludeFromFees(address(dexRouter), true);
            
                    _createInitialSupply(address(newOwner), totalSupply);
                    transferOwnership(newOwner);
            
                    _approve(address(this), address(dexRouter), type(uint256).max);
                    _approve(address(newOwner), address(dexRouter), totalSupply);
                }
            
                receive() external payable {}
            
                // Owner Functions
            
                function enableTrading() external onlyOwner {
                    require(tradingActiveBlock == 0, "enableTrading already called");
                    tradingActive = true;
                    swapEnabled = true;
                    tradingActiveBlock = block.number;
                    emit EnabledTrading();
                }
            
                function pauseTrading() external onlyOwner {
                    require(tradingActiveBlock > 0, "enableTrading first");
                    require(tradingActive, "Trading paused");
                    tradingActive = false;
                }
            
                function unpauseTrading() external onlyOwner {
                    require(tradingActiveBlock > 0, "enableTrading first");
                    require(!tradingActive, "Trading unpaused");
                    tradingActive = true;
                }
            
                function manageRestrictedWallets(address[] calldata wallets,  bool restricted) external onlyOwner {
                    for(uint256 i = 0; i < wallets.length; i++){
                        restrictedWallets[wallets[i]] = restricted;
                    }
                }
                
                function removeLimits() external onlyOwner {
                    limitsInEffect = false;
                    maxTxnAmount = totalSupply();
                    emit RemovedLimits();
                }
            
                function updateMaxTxnAmount(uint256 newNum) external onlyOwner {
                    require(newNum >= (totalSupply() * 1 / 1000)/1e18, "too low");
                    maxTxnAmount = newNum * (10**18);
                    emit UpdatedMaxTxnAmount(maxTxnAmount);
                }
            
                // change the minimum amount of tokens to sell from fees
                function updateSwapTokensAtAmount(uint256 newAmount) external onlyOwner {
              	    require(newAmount >= totalSupply() * 1 / 1000000, "too low");
              	    require(newAmount <= totalSupply() * 1 / 1000, "too high");
              	    swapTokensAtAmount = newAmount;
              	}
                
                function transferForeignToken(address _token, address _to) external onlyOwner returns (bool _sent) {
                    require(_token != address(0), "zero address");
                    require(_token != address(this), "Can't withdraw native tokens");
                    uint256 _contractBalance = IERC20(_token).balanceOf(address(this));
                    _sent = IERC20(_token).transfer(_to, _contractBalance);
                    emit TransferForeignToken(_token, _contractBalance);
                }
            
                // withdraw ETH if stuck or someone sends to the address
                function withdrawStuckETH() external onlyOwner {
                    bool success;
                    (success,) = address(msg.sender).call{value: address(this).balance}("");
                }
            
                function setImpactAddress(address _impactAddress) external onlyOwner {
                    require(_impactAddress != address(0), "zero address");
                    impactAddress = payable(_impactAddress);
                    emit UpdatedImpactAddress(_impactAddress);
                }
            
                function setCRFAddress(address _crfAddress) external onlyOwner {
                    require(_crfAddress != address(0), "zero address");
                    crfAddress = payable(_crfAddress);
                    emit UpdatedCRFAddress(_crfAddress);
                }
                
                function setLiquidityAddress(address _liquidityAddress) external onlyOwner {
                    require(_liquidityAddress != address(0), "zero address");
                    liquidityAddress = payable(_liquidityAddress);
                    emit UpdatedLiquidityAddress(_liquidityAddress);
                }
            
                function setOperationsAddress(address _operationsAddress) external onlyOwner {
                    require(_operationsAddress != address(0), "zero address");
                    operationsAddress = payable(_operationsAddress);
                    emit UpdatedOperationsAddress(_operationsAddress);
                }
            
                function setTreasuryAddress(address _treasuryAddress) external onlyOwner {
                    require(_treasuryAddress != address(0), "zero address");
                    treasuryAddress = payable(_treasuryAddress);
                    emit UpdatedTreasuryAddress(_treasuryAddress);
                }
            
                function forceSwapBack() external onlyOwner {
                    require(balanceOf(address(this)) >= swapTokensAtAmount, "Amount not high enough");
                    swapping = true;
                    swapBackEth();
                    swapping = false;
                    emit OwnerForcedSwapBack(block.timestamp);
                }
                
                function airdropToWallets(address[] memory wallets, uint256[] memory amountsInTokens) external onlyOwner {
                    require(wallets.length == amountsInTokens.length, "length mismatch");
                    require(wallets.length < 600, "600 max");
                    for(uint256 i = 0; i < wallets.length; i++){
                        address wallet = wallets[i];
                        uint256 amount = amountsInTokens[i];
                        super._transfer(msg.sender, wallet, amount);
                    }
                }
                
                function excludeFromMaxTransaction(address updAds, bool isEx) external onlyOwner {
                    if(!isEx){
                        require(updAds != lpPairEth, "pair cannot be removed");
                    }
                    _isExcludedMaxTransactionAmount[updAds] = isEx;
                }
            
                function setAutomatedMarketMakerPair(address pair, bool value) public onlyOwner {
                    require(pair != lpPairEth || value, "pair cannot be removed");
                    automatedMarketMakerPairs[pair] = value;
                    _excludeFromMaxTransaction(pair, value);
                    emit SetAutomatedMarketMakerPair(pair, value);
                }
            
                function updateBuyFees(uint256 _impactFee, uint256 _liquidityFee, uint256 _crfFee, uint256 _operationsFee, uint256 _treasuryFee) external onlyOwner {
                    buyImpactFee = _impactFee;
                    buyLiquidityFee = _liquidityFee;
                    buyCRFFee = _crfFee;
                    buyOperationsFee = _operationsFee;
                    buyTreasuryFee = _treasuryFee;
                    buyTotalFees = buyImpactFee + buyLiquidityFee + buyCRFFee + buyOperationsFee + buyTreasuryFee;
                    require(buyTotalFees <= 1000, "Fees too high");
                    emit UpdatedBuyFee(buyTotalFees);
                }
            
                function updateSellFees(uint256 _impactFee, uint256 _liquidityFee, uint256 _crfFee, uint256 _operationsFee, uint256 _treasuryFee) external onlyOwner {
                    sellImpactFee = _impactFee;
                    sellLiquidityFee = _liquidityFee;
                    sellCRFFee = _crfFee;
                    sellOperationsFee = _operationsFee;
                    sellTreasuryFee = _treasuryFee;
                    sellTotalFees = sellImpactFee + sellLiquidityFee + sellCRFFee + sellOperationsFee + sellTreasuryFee;
                    require(sellTotalFees <= 1000, "Fees too high");
                    emit UpdatedSellFee(sellTotalFees);
                }
            
                function excludeFromFees(address account, bool excluded) public onlyOwner {
                    _isExcludedFromFees[account] = excluded;
                    emit ExcludeFromFees(account, excluded);
                }
            
                // private / internal functions
            
                function _transfer(address from, address to, uint256 amount) internal override {
            
                    require(from != address(0), "ERC20: transfer from the zero address");
                    require(to != address(0), "ERC20: transfer to the zero address");
                    // transfer of 0 is allowed, but triggers no logic.  In case of staking where a staking pool is paying out 0 rewards.
                    if(amount == 0){
                        super._transfer(from, to, 0);
                        return;
                    }
            
                    require(!restrictedWallets[from] && !restrictedWallets[to], "blocked address");
                    
                    if(_isExcludedFromFees[from] || _isExcludedFromFees[to]){
                        super._transfer(from, to, amount);
                        return;
                    }
                    
                    require(tradingActive, "Trading is not active.");
            
                    
            
                    if(limitsInEffect){
                        //on buy or sell
                        if ((automatedMarketMakerPairs[from] && !_isExcludedMaxTransactionAmount[to]) || (automatedMarketMakerPairs[to] && !_isExcludedMaxTransactionAmount[from])) {
                            require(amount <= maxTxnAmount, "max tx exceeded");
                        }
                    }
            
                    if(balanceOf(address(this)) >= swapTokensAtAmount && swapEnabled && !swapping && automatedMarketMakerPairs[to]) {
                        swapping = true;
                        swapBackEth();
                        swapping = false;
                    }
            
                    uint256 fees = 0;
            
                    // only take fees on buys/sells, do not take on wallet transfers
                    // on sell
                    if (automatedMarketMakerPairs[to] && sellTotalFees > 0){
                        fees = amount * sellTotalFees / FEE_DIVISOR;
                        tokensForLiquidity += fees * sellLiquidityFee / sellTotalFees;
                        tokensForImpact += fees * sellImpactFee / sellTotalFees;
                        tokensForCRF += fees * sellCRFFee / sellTotalFees;
                        tokensForOperations += fees * sellOperationsFee / sellTotalFees;
                        tokensForTreasury += fees * sellTreasuryFee / sellTotalFees;
                    }
            
                    // on buy
                    else if(automatedMarketMakerPairs[from] && buyTotalFees > 0) {
                        fees = amount * buyTotalFees / FEE_DIVISOR;
                        tokensForImpact += fees * buyImpactFee / buyTotalFees;
                        tokensForLiquidity += fees * buyLiquidityFee / buyTotalFees;
                        tokensForCRF += fees * buyCRFFee / buyTotalFees;
                        tokensForOperations += fees * buyOperationsFee / buyTotalFees;
                        tokensForTreasury += fees * buyTreasuryFee / buyTotalFees;
                    }
                    
                    if(fees > 0){    
                        super._transfer(from, address(this), fees);
                    }
                    
                    amount -= fees;
            
                    super._transfer(from, to, amount);
                }
            
                function swapBackEth() private {
                    bool success;
            
                    uint256 contractBalance = balanceOf(address(this));
                    uint256 totalTokensToSwap = tokensForLiquidity + tokensForImpact + tokensForCRF + tokensForOperations + tokensForTreasury;
                    
                    if(contractBalance == 0 || totalTokensToSwap == 0) {return;}
            
                    if(contractBalance > swapTokensAtAmount * 10){
                        contractBalance = swapTokensAtAmount * 10;
                    }
                    
                    // Halve the amount of liquidity tokens
                    uint256 liquidityTokens = contractBalance * tokensForLiquidity / totalTokensToSwap / 2;
                    
                    swapTokensForEth(contractBalance - liquidityTokens);
                    
                    uint256 ethBalance = address(this).balance;
                    uint256 ethForLiquidity = ethBalance;
            
                    uint256 ethForImpact = ethBalance * tokensForImpact / (totalTokensToSwap - (tokensForLiquidity/2));
                    uint256 ethForCRF = ethBalance * tokensForCRF / (totalTokensToSwap - (tokensForLiquidity/2));
                    uint256 ethForOperations = ethBalance * tokensForOperations / (totalTokensToSwap - (tokensForLiquidity/2));
                    uint256 ethForTreasury = ethBalance * tokensForTreasury / (totalTokensToSwap - (tokensForLiquidity/2));
            
                    ethForLiquidity -= ethForImpact + ethForCRF + ethForOperations + ethForTreasury;
                        
                    tokensForLiquidity = 0;
                    tokensForImpact = 0;
                    tokensForCRF = 0;
                    tokensForOperations = 0;
                    tokensForTreasury = 0;
                    
                    if(liquidityTokens > 0 && ethForLiquidity > 0){
                        addLiquidityEth(liquidityTokens, ethForLiquidity);
                    }
            
                    if(ethForCRF > 0){
                        (success, ) = crfAddress.call{value: ethForCRF}("");
                    }
            
                    if(ethForOperations > 0){
                        (success, ) = operationsAddress.call{value: ethForOperations}("");
                    }
            
                     if(ethForTreasury > 0){
                        (success, ) = treasuryAddress.call{value: ethForTreasury}("");
                    }
            
                    if(address(this).balance > 0){
                        (success, ) = impactAddress.call{value: address(this).balance}("");
                    }
                }
            
                function addLiquidityEth(uint256 tokenAmount, uint256 ethAmount) private {
                    // add the liquidity
                    dexRouter.addLiquidityETH{value: ethAmount}(address(this), tokenAmount, 0, 0, address(liquidityAddress), block.timestamp);
                }
            
                function swapTokensForEth(uint256 tokenAmount) private {
            
                    // generate the uniswap pair path of token -> weth
                    address[] memory path = new address[](2);
                    path[0] = address(this);
                    path[1] = dexRouter.WETH();
            
                    // make the swap
                    dexRouter.swapExactTokensForETHSupportingFeeOnTransferTokens(tokenAmount, 0, path, address(this), block.timestamp);
                }
            
                function _excludeFromMaxTransaction(address updAds, bool isExcluded) private {
                    _isExcludedMaxTransactionAmount[updAds] = isExcluded;
                    emit MaxTransactionExclusion(updAds, isExcluded);
                }
            
                //views
            
                function getTier(address account) external view returns (uint256){
                    uint256 accountBalance = balanceOf(account);
                    uint256 supply = totalSupply();
                    if(accountBalance * 1e18 / supply >= 0.00075 ether){
                        return 5;
                    }
                    if(accountBalance * 1e18 / supply >= 0.00060 ether){
                        return 4;
                    }
                    if(accountBalance * 1e18 / supply >= 0.00045 ether){
                        return 3;
                    }
                    if(accountBalance * 1e18 / supply >= 0.00030 ether){
                        return 2;
                    }
                    if(accountBalance * 1e18 / supply >= 0.00015 ether){
                        return 1;
                    }
                    return 0;
                }
            }

            File 3 of 5: Vault
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            pragma experimental ABIEncoderV2;
            import "./interfaces/IAuthorizer.sol";
            import "./interfaces/IWETH.sol";
            import "./VaultAuthorization.sol";
            import "./FlashLoans.sol";
            import "./Swaps.sol";
            /**
             * @dev The `Vault` is Balancer V2's core contract. A single instance of it exists for the entire network, and it is the
             * entity used to interact with Pools by Liquidity Providers who join and exit them, Traders who swap, and Asset
             * Managers who withdraw and deposit tokens.
             *
             * The `Vault`'s source code is split among a number of sub-contracts, with the goal of improving readability and making
             * understanding the system easier. Most sub-contracts have been marked as `abstract` to explicitly indicate that only
             * the full `Vault` is meant to be deployed.
             *
             * Roughly speaking, these are the contents of each sub-contract:
             *
             *  - `AssetManagers`: Pool token Asset Manager registry, and Asset Manager interactions.
             *  - `Fees`: set and compute protocol fees.
             *  - `FlashLoans`: flash loan transfers and fees.
             *  - `PoolBalances`: Pool joins and exits.
             *  - `PoolRegistry`: Pool registration, ID management, and basic queries.
             *  - `PoolTokens`: Pool token registration and registration, and balance queries.
             *  - `Swaps`: Pool swaps.
             *  - `UserBalance`: manage user balances (Internal Balance operations and external balance transfers)
             *  - `VaultAuthorization`: access control, relayers and signature validation.
             *
             * Additionally, the different Pool specializations are handled by the `GeneralPoolsBalance`,
             * `MinimalSwapInfoPoolsBalance` and `TwoTokenPoolsBalance` sub-contracts, which in turn make use of the
             * `BalanceAllocation` library.
             *
             * The most important goal of the `Vault` is to make token swaps use as little gas as possible. This is reflected in a
             * multitude of design decisions, from minor things like the format used to store Pool IDs, to major features such as
             * the different Pool specialization settings.
             *
             * Finally, the large number of tasks carried out by the Vault means its bytecode is very large, close to exceeding
             * the contract size limit imposed by EIP 170 (https://eips.ethereum.org/EIPS/eip-170). Manual tuning of the source code
             * was required to improve code generation and bring the bytecode size below this limit. This includes extensive
             * utilization of `internal` functions (particularly inside modifiers), usage of named return arguments, dedicated
             * storage access methods, dynamic revert reason generation, and usage of inline assembly, to name a few.
             */
            contract Vault is VaultAuthorization, FlashLoans, Swaps {
                constructor(
                    IAuthorizer authorizer,
                    IWETH weth,
                    uint256 pauseWindowDuration,
                    uint256 bufferPeriodDuration
                ) VaultAuthorization(authorizer) AssetHelpers(weth) TemporarilyPausable(pauseWindowDuration, bufferPeriodDuration) {
                    // solhint-disable-previous-line no-empty-blocks
                }
                function setPaused(bool paused) external override nonReentrant authenticate {
                    _setPaused(paused);
                }
                // solhint-disable-next-line func-name-mixedcase
                function WETH() external view override returns (IWETH) {
                    return _WETH();
                }
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            interface IAuthorizer {
                /**
                 * @dev Returns true if `account` can perform the action described by `actionId` in the contract `where`.
                 */
                function canPerform(
                    bytes32 actionId,
                    address account,
                    address where
                ) external view returns (bool);
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            import "../../lib/openzeppelin/IERC20.sol";
            /**
             * @dev Interface for the WETH token contract used internally for wrapping and unwrapping, to support
             * sending and receiving ETH in joins, swaps, and internal balance deposits and withdrawals.
             */
            interface IWETH is IERC20 {
                function deposit() external payable;
                function withdraw(uint256 amount) external;
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            pragma experimental ABIEncoderV2;
            import "../lib/helpers/BalancerErrors.sol";
            import "../lib/helpers/Authentication.sol";
            import "../lib/helpers/TemporarilyPausable.sol";
            import "../lib/helpers/BalancerErrors.sol";
            import "../lib/helpers/SignaturesValidator.sol";
            import "../lib/openzeppelin/ReentrancyGuard.sol";
            import "./interfaces/IVault.sol";
            import "./interfaces/IAuthorizer.sol";
            /**
             * @dev Manages access control of Vault permissioned functions by relying on the Authorizer and signature validation.
             *
             * Additionally handles relayer access and approval.
             */
            abstract contract VaultAuthorization is
                IVault,
                ReentrancyGuard,
                Authentication,
                SignaturesValidator,
                TemporarilyPausable
            {
                // Ideally, we'd store the type hashes as immutable state variables to avoid computing the hash at runtime, but
                // unfortunately immutable variables cannot be used in assembly, so we just keep the precomputed hashes instead.
                // _JOIN_TYPE_HASH = keccak256("JoinPool(bytes calldata,address sender,uint256 nonce,uint256 deadline)");
                bytes32 private constant _JOIN_TYPE_HASH = 0x3f7b71252bd19113ff48c19c6e004a9bcfcca320a0d74d58e85877cbd7dcae58;
                // _EXIT_TYPE_HASH = keccak256("ExitPool(bytes calldata,address sender,uint256 nonce,uint256 deadline)");
                bytes32 private constant _EXIT_TYPE_HASH = 0x8bbc57f66ea936902f50a71ce12b92c43f3c5340bb40c27c4e90ab84eeae3353;
                // _SWAP_TYPE_HASH = keccak256("Swap(bytes calldata,address sender,uint256 nonce,uint256 deadline)");
                bytes32 private constant _SWAP_TYPE_HASH = 0xe192dcbc143b1e244ad73b813fd3c097b832ad260a157340b4e5e5beda067abe;
                // _BATCH_SWAP_TYPE_HASH = keccak256("BatchSwap(bytes calldata,address sender,uint256 nonce,uint256 deadline)");
                bytes32 private constant _BATCH_SWAP_TYPE_HASH = 0x9bfc43a4d98313c6766986ffd7c916c7481566d9f224c6819af0a53388aced3a;
                // _SET_RELAYER_TYPE_HASH =
                //     keccak256("SetRelayerApproval(bytes calldata,address sender,uint256 nonce,uint256 deadline)");
                bytes32
                    private constant _SET_RELAYER_TYPE_HASH = 0xa3f865aa351e51cfeb40f5178d1564bb629fe9030b83caf6361d1baaf5b90b5a;
                IAuthorizer private _authorizer;
                mapping(address => mapping(address => bool)) private _approvedRelayers;
                /**
                 * @dev Reverts unless `user` is the caller, or the caller is approved by the Authorizer to call this function (that
                 * is, it is a relayer for that function), and either:
                 *  a) `user` approved the caller as a relayer (via `setRelayerApproval`), or
                 *  b) a valid signature from them was appended to the calldata.
                 *
                 * Should only be applied to external functions.
                 */
                modifier authenticateFor(address user) {
                    _authenticateFor(user);
                    _;
                }
                constructor(IAuthorizer authorizer)
                    // The Vault is a singleton, so it simply uses its own address to disambiguate action identifiers.
                    Authentication(bytes32(uint256(address(this))))
                    SignaturesValidator("Balancer V2 Vault")
                {
                    _setAuthorizer(authorizer);
                }
                function setAuthorizer(IAuthorizer newAuthorizer) external override nonReentrant authenticate {
                    _setAuthorizer(newAuthorizer);
                }
                function _setAuthorizer(IAuthorizer newAuthorizer) private {
                    emit AuthorizerChanged(newAuthorizer);
                    _authorizer = newAuthorizer;
                }
                function getAuthorizer() external view override returns (IAuthorizer) {
                    return _authorizer;
                }
                function setRelayerApproval(
                    address sender,
                    address relayer,
                    bool approved
                ) external override nonReentrant whenNotPaused authenticateFor(sender) {
                    _approvedRelayers[sender][relayer] = approved;
                    emit RelayerApprovalChanged(relayer, sender, approved);
                }
                function hasApprovedRelayer(address user, address relayer) external view override returns (bool) {
                    return _hasApprovedRelayer(user, relayer);
                }
                /**
                 * @dev Reverts unless `user` is the caller, or the caller is approved by the Authorizer to call the entry point
                 * function (that is, it is a relayer for that function) and either:
                 *  a) `user` approved the caller as a relayer (via `setRelayerApproval`), or
                 *  b) a valid signature from them was appended to the calldata.
                 */
                function _authenticateFor(address user) internal {
                    if (msg.sender != user) {
                        // In this context, 'permission to call a function' means 'being a relayer for a function'.
                        _authenticateCaller();
                        // Being a relayer is not sufficient: `user` must have also approved the caller either via
                        // `setRelayerApproval`, or by providing a signature appended to the calldata.
                        if (!_hasApprovedRelayer(user, msg.sender)) {
                            _validateSignature(user, Errors.USER_DOESNT_ALLOW_RELAYER);
                        }
                    }
                }
                /**
                 * @dev Returns true if `user` approved `relayer` to act as a relayer for them.
                 */
                function _hasApprovedRelayer(address user, address relayer) internal view returns (bool) {
                    return _approvedRelayers[user][relayer];
                }
                function _canPerform(bytes32 actionId, address user) internal view override returns (bool) {
                    // Access control is delegated to the Authorizer.
                    return _authorizer.canPerform(actionId, user, address(this));
                }
                function _typeHash() internal pure override returns (bytes32 hash) {
                    // This is a simple switch-case statement, trivially written in Solidity by chaining else-if statements, but the
                    // assembly implementation results in much denser bytecode.
                    // solhint-disable-next-line no-inline-assembly
                    assembly {
                        // The function selector is located at the first 4 bytes of calldata. We copy the first full calldata
                        // 256 word, and then perform a logical shift to the right, moving the selector to the least significant
                        // 4 bytes.
                        let selector := shr(224, calldataload(0))
                        // With the selector in the least significant 4 bytes, we can use 4 byte literals with leading zeros,
                        // resulting in dense bytecode (PUSH4 opcodes).
                        switch selector
                            case 0xb95cac28 {
                                hash := _JOIN_TYPE_HASH
                            }
                            case 0x8bdb3913 {
                                hash := _EXIT_TYPE_HASH
                            }
                            case 0x52bbbe29 {
                                hash := _SWAP_TYPE_HASH
                            }
                            case 0x945bcec9 {
                                hash := _BATCH_SWAP_TYPE_HASH
                            }
                            case 0xfa6e671d {
                                hash := _SET_RELAYER_TYPE_HASH
                            }
                            default {
                                hash := 0x0000000000000000000000000000000000000000000000000000000000000000
                            }
                    }
                }
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            // This flash loan provider was based on the Aave protocol's open source
            // implementation and terminology and interfaces are intentionally kept
            // similar
            pragma solidity ^0.7.0;
            pragma experimental ABIEncoderV2;
            import "../lib/helpers/BalancerErrors.sol";
            import "../lib/openzeppelin/IERC20.sol";
            import "../lib/openzeppelin/ReentrancyGuard.sol";
            import "../lib/openzeppelin/SafeERC20.sol";
            import "./Fees.sol";
            import "./interfaces/IFlashLoanRecipient.sol";
            /**
             * @dev Handles Flash Loans through the Vault. Calls the `receiveFlashLoan` hook on the flash loan recipient
             * contract, which implements the `IFlashLoanRecipient` interface.
             */
            abstract contract FlashLoans is Fees, ReentrancyGuard, TemporarilyPausable {
                using SafeERC20 for IERC20;
                function flashLoan(
                    IFlashLoanRecipient recipient,
                    IERC20[] memory tokens,
                    uint256[] memory amounts,
                    bytes memory userData
                ) external override nonReentrant whenNotPaused {
                    InputHelpers.ensureInputLengthMatch(tokens.length, amounts.length);
                    uint256[] memory feeAmounts = new uint256[](tokens.length);
                    uint256[] memory preLoanBalances = new uint256[](tokens.length);
                    // Used to ensure `tokens` is sorted in ascending order, which ensures token uniqueness.
                    IERC20 previousToken = IERC20(0);
                    for (uint256 i = 0; i < tokens.length; ++i) {
                        IERC20 token = tokens[i];
                        uint256 amount = amounts[i];
                        _require(token > previousToken, token == IERC20(0) ? Errors.ZERO_TOKEN : Errors.UNSORTED_TOKENS);
                        previousToken = token;
                        preLoanBalances[i] = token.balanceOf(address(this));
                        feeAmounts[i] = _calculateFlashLoanFeeAmount(amount);
                        _require(preLoanBalances[i] >= amount, Errors.INSUFFICIENT_FLASH_LOAN_BALANCE);
                        token.safeTransfer(address(recipient), amount);
                    }
                    recipient.receiveFlashLoan(tokens, amounts, feeAmounts, userData);
                    for (uint256 i = 0; i < tokens.length; ++i) {
                        IERC20 token = tokens[i];
                        uint256 preLoanBalance = preLoanBalances[i];
                        // Checking for loan repayment first (without accounting for fees) makes for simpler debugging, and results
                        // in more accurate revert reasons if the flash loan protocol fee percentage is zero.
                        uint256 postLoanBalance = token.balanceOf(address(this));
                        _require(postLoanBalance >= preLoanBalance, Errors.INVALID_POST_LOAN_BALANCE);
                        // No need for checked arithmetic since we know the loan was fully repaid.
                        uint256 receivedFeeAmount = postLoanBalance - preLoanBalance;
                        _require(receivedFeeAmount >= feeAmounts[i], Errors.INSUFFICIENT_FLASH_LOAN_FEE_AMOUNT);
                        _payFeeAmount(token, receivedFeeAmount);
                        emit FlashLoan(recipient, token, amounts[i], receivedFeeAmount);
                    }
                }
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            pragma experimental ABIEncoderV2;
            import "../lib/math/Math.sol";
            import "../lib/helpers/BalancerErrors.sol";
            import "../lib/helpers/InputHelpers.sol";
            import "../lib/openzeppelin/EnumerableMap.sol";
            import "../lib/openzeppelin/EnumerableSet.sol";
            import "../lib/openzeppelin/IERC20.sol";
            import "../lib/openzeppelin/ReentrancyGuard.sol";
            import "../lib/openzeppelin/SafeCast.sol";
            import "../lib/openzeppelin/SafeERC20.sol";
            import "./PoolBalances.sol";
            import "./interfaces/IPoolSwapStructs.sol";
            import "./interfaces/IGeneralPool.sol";
            import "./interfaces/IMinimalSwapInfoPool.sol";
            import "./balances/BalanceAllocation.sol";
            /**
             * Implements the Vault's high-level swap functionality.
             *
             * Users can swap tokens with Pools by calling the `swap` and `batchSwap` functions. They need not trust the Pool
             * contracts to do this: all security checks are made by the Vault.
             *
             * The `swap` function executes a single swap, while `batchSwap` can perform multiple swaps in sequence.
             * In each individual swap, tokens of one kind are sent from the sender to the Pool (this is the 'token in'),
             * and tokens of another kind are sent from the Pool to the recipient in exchange (this is the 'token out').
             * More complex swaps, such as one 'token in' to multiple tokens out can be achieved by batching together
             * individual swaps.
             */
            abstract contract Swaps is ReentrancyGuard, PoolBalances {
                using SafeERC20 for IERC20;
                using EnumerableSet for EnumerableSet.AddressSet;
                using EnumerableMap for EnumerableMap.IERC20ToBytes32Map;
                using Math for int256;
                using Math for uint256;
                using SafeCast for uint256;
                using BalanceAllocation for bytes32;
                function swap(
                    SingleSwap memory singleSwap,
                    FundManagement memory funds,
                    uint256 limit,
                    uint256 deadline
                )
                    external
                    payable
                    override
                    nonReentrant
                    whenNotPaused
                    authenticateFor(funds.sender)
                    returns (uint256 amountCalculated)
                {
                    // The deadline is timestamp-based: it should not be relied upon for sub-minute accuracy.
                    // solhint-disable-next-line not-rely-on-time
                    _require(block.timestamp <= deadline, Errors.SWAP_DEADLINE);
                    // This revert reason is for consistency with `batchSwap`: an equivalent `swap` performed using that function
                    // would result in this error.
                    _require(singleSwap.amount > 0, Errors.UNKNOWN_AMOUNT_IN_FIRST_SWAP);
                    IERC20 tokenIn = _translateToIERC20(singleSwap.assetIn);
                    IERC20 tokenOut = _translateToIERC20(singleSwap.assetOut);
                    _require(tokenIn != tokenOut, Errors.CANNOT_SWAP_SAME_TOKEN);
                    // Initializing each struct field one-by-one uses less gas than setting all at once.
                    IPoolSwapStructs.SwapRequest memory poolRequest;
                    poolRequest.poolId = singleSwap.poolId;
                    poolRequest.kind = singleSwap.kind;
                    poolRequest.tokenIn = tokenIn;
                    poolRequest.tokenOut = tokenOut;
                    poolRequest.amount = singleSwap.amount;
                    poolRequest.userData = singleSwap.userData;
                    poolRequest.from = funds.sender;
                    poolRequest.to = funds.recipient;
                    // The lastChangeBlock field is left uninitialized.
                    uint256 amountIn;
                    uint256 amountOut;
                    (amountCalculated, amountIn, amountOut) = _swapWithPool(poolRequest);
                    _require(singleSwap.kind == SwapKind.GIVEN_IN ? amountOut >= limit : amountIn <= limit, Errors.SWAP_LIMIT);
                    _receiveAsset(singleSwap.assetIn, amountIn, funds.sender, funds.fromInternalBalance);
                    _sendAsset(singleSwap.assetOut, amountOut, funds.recipient, funds.toInternalBalance);
                    // If the asset in is ETH, then `amountIn` ETH was wrapped into WETH.
                    _handleRemainingEth(_isETH(singleSwap.assetIn) ? amountIn : 0);
                }
                function batchSwap(
                    SwapKind kind,
                    BatchSwapStep[] memory swaps,
                    IAsset[] memory assets,
                    FundManagement memory funds,
                    int256[] memory limits,
                    uint256 deadline
                )
                    external
                    payable
                    override
                    nonReentrant
                    whenNotPaused
                    authenticateFor(funds.sender)
                    returns (int256[] memory assetDeltas)
                {
                    // The deadline is timestamp-based: it should not be relied upon for sub-minute accuracy.
                    // solhint-disable-next-line not-rely-on-time
                    _require(block.timestamp <= deadline, Errors.SWAP_DEADLINE);
                    InputHelpers.ensureInputLengthMatch(assets.length, limits.length);
                    // Perform the swaps, updating the Pool token balances and computing the net Vault asset deltas.
                    assetDeltas = _swapWithPools(swaps, assets, funds, kind);
                    // Process asset deltas, by either transferring assets from the sender (for positive deltas) or to the recipient
                    // (for negative deltas).
                    uint256 wrappedEth = 0;
                    for (uint256 i = 0; i < assets.length; ++i) {
                        IAsset asset = assets[i];
                        int256 delta = assetDeltas[i];
                        _require(delta <= limits[i], Errors.SWAP_LIMIT);
                        if (delta > 0) {
                            uint256 toReceive = uint256(delta);
                            _receiveAsset(asset, toReceive, funds.sender, funds.fromInternalBalance);
                            if (_isETH(asset)) {
                                wrappedEth = wrappedEth.add(toReceive);
                            }
                        } else if (delta < 0) {
                            uint256 toSend = uint256(-delta);
                            _sendAsset(asset, toSend, funds.recipient, funds.toInternalBalance);
                        }
                    }
                    // Handle any used and remaining ETH.
                    _handleRemainingEth(wrappedEth);
                }
                // For `_swapWithPools` to handle both 'given in' and 'given out' swaps, it internally tracks the 'given' amount
                // (supplied by the caller), and the 'calculated' amount (returned by the Pool in response to the swap request).
                /**
                 * @dev Given the two swap tokens and the swap kind, returns which one is the 'given' token (the token whose
                 * amount is supplied by the caller).
                 */
                function _tokenGiven(
                    SwapKind kind,
                    IERC20 tokenIn,
                    IERC20 tokenOut
                ) private pure returns (IERC20) {
                    return kind == SwapKind.GIVEN_IN ? tokenIn : tokenOut;
                }
                /**
                 * @dev Given the two swap tokens and the swap kind, returns which one is the 'calculated' token (the token whose
                 * amount is calculated by the Pool).
                 */
                function _tokenCalculated(
                    SwapKind kind,
                    IERC20 tokenIn,
                    IERC20 tokenOut
                ) private pure returns (IERC20) {
                    return kind == SwapKind.GIVEN_IN ? tokenOut : tokenIn;
                }
                /**
                 * @dev Returns an ordered pair (amountIn, amountOut) given the 'given' and 'calculated' amounts, and the swap kind.
                 */
                function _getAmounts(
                    SwapKind kind,
                    uint256 amountGiven,
                    uint256 amountCalculated
                ) private pure returns (uint256 amountIn, uint256 amountOut) {
                    if (kind == SwapKind.GIVEN_IN) {
                        (amountIn, amountOut) = (amountGiven, amountCalculated);
                    } else {
                        // SwapKind.GIVEN_OUT
                        (amountIn, amountOut) = (amountCalculated, amountGiven);
                    }
                }
                /**
                 * @dev Performs all `swaps`, calling swap hooks on the Pool contracts and updating their balances. Does not cause
                 * any transfer of tokens - instead it returns the net Vault token deltas: positive if the Vault should receive
                 * tokens, and negative if it should send them.
                 */
                function _swapWithPools(
                    BatchSwapStep[] memory swaps,
                    IAsset[] memory assets,
                    FundManagement memory funds,
                    SwapKind kind
                ) private returns (int256[] memory assetDeltas) {
                    assetDeltas = new int256[](assets.length);
                    // These variables could be declared inside the loop, but that causes the compiler to allocate memory on each
                    // loop iteration, increasing gas costs.
                    BatchSwapStep memory batchSwapStep;
                    IPoolSwapStructs.SwapRequest memory poolRequest;
                    // These store data about the previous swap here to implement multihop logic across swaps.
                    IERC20 previousTokenCalculated;
                    uint256 previousAmountCalculated;
                    for (uint256 i = 0; i < swaps.length; ++i) {
                        batchSwapStep = swaps[i];
                        bool withinBounds = batchSwapStep.assetInIndex < assets.length &&
                            batchSwapStep.assetOutIndex < assets.length;
                        _require(withinBounds, Errors.OUT_OF_BOUNDS);
                        IERC20 tokenIn = _translateToIERC20(assets[batchSwapStep.assetInIndex]);
                        IERC20 tokenOut = _translateToIERC20(assets[batchSwapStep.assetOutIndex]);
                        _require(tokenIn != tokenOut, Errors.CANNOT_SWAP_SAME_TOKEN);
                        // Sentinel value for multihop logic
                        if (batchSwapStep.amount == 0) {
                            // When the amount given is zero, we use the calculated amount for the previous swap, as long as the
                            // current swap's given token is the previous calculated token. This makes it possible to swap a
                            // given amount of token A for token B, and then use the resulting token B amount to swap for token C.
                            _require(i > 0, Errors.UNKNOWN_AMOUNT_IN_FIRST_SWAP);
                            bool usingPreviousToken = previousTokenCalculated == _tokenGiven(kind, tokenIn, tokenOut);
                            _require(usingPreviousToken, Errors.MALCONSTRUCTED_MULTIHOP_SWAP);
                            batchSwapStep.amount = previousAmountCalculated;
                        }
                        // Initializing each struct field one-by-one uses less gas than setting all at once
                        poolRequest.poolId = batchSwapStep.poolId;
                        poolRequest.kind = kind;
                        poolRequest.tokenIn = tokenIn;
                        poolRequest.tokenOut = tokenOut;
                        poolRequest.amount = batchSwapStep.amount;
                        poolRequest.userData = batchSwapStep.userData;
                        poolRequest.from = funds.sender;
                        poolRequest.to = funds.recipient;
                        // The lastChangeBlock field is left uninitialized
                        uint256 amountIn;
                        uint256 amountOut;
                        (previousAmountCalculated, amountIn, amountOut) = _swapWithPool(poolRequest);
                        previousTokenCalculated = _tokenCalculated(kind, tokenIn, tokenOut);
                        // Accumulate Vault deltas across swaps
                        assetDeltas[batchSwapStep.assetInIndex] = assetDeltas[batchSwapStep.assetInIndex].add(amountIn.toInt256());
                        assetDeltas[batchSwapStep.assetOutIndex] = assetDeltas[batchSwapStep.assetOutIndex].sub(
                            amountOut.toInt256()
                        );
                    }
                }
                /**
                 * @dev Performs a swap according to the parameters specified in `request`, calling the Pool's contract hook and
                 * updating the Pool's balance.
                 *
                 * Returns the amount of tokens going into or out of the Vault as a result of this swap, depending on the swap kind.
                 */
                function _swapWithPool(IPoolSwapStructs.SwapRequest memory request)
                    private
                    returns (
                        uint256 amountCalculated,
                        uint256 amountIn,
                        uint256 amountOut
                    )
                {
                    // Get the calculated amount from the Pool and update its balances
                    address pool = _getPoolAddress(request.poolId);
                    PoolSpecialization specialization = _getPoolSpecialization(request.poolId);
                    if (specialization == PoolSpecialization.TWO_TOKEN) {
                        amountCalculated = _processTwoTokenPoolSwapRequest(request, IMinimalSwapInfoPool(pool));
                    } else if (specialization == PoolSpecialization.MINIMAL_SWAP_INFO) {
                        amountCalculated = _processMinimalSwapInfoPoolSwapRequest(request, IMinimalSwapInfoPool(pool));
                    } else {
                        // PoolSpecialization.GENERAL
                        amountCalculated = _processGeneralPoolSwapRequest(request, IGeneralPool(pool));
                    }
                    (amountIn, amountOut) = _getAmounts(request.kind, request.amount, amountCalculated);
                    emit Swap(request.poolId, request.tokenIn, request.tokenOut, amountIn, amountOut);
                }
                function _processTwoTokenPoolSwapRequest(IPoolSwapStructs.SwapRequest memory request, IMinimalSwapInfoPool pool)
                    private
                    returns (uint256 amountCalculated)
                {
                    // For gas efficiency reasons, this function uses low-level knowledge of how Two Token Pool balances are
                    // stored internally, instead of using getters and setters for all operations.
                    (
                        bytes32 tokenABalance,
                        bytes32 tokenBBalance,
                        TwoTokenPoolBalances storage poolBalances
                    ) = _getTwoTokenPoolSharedBalances(request.poolId, request.tokenIn, request.tokenOut);
                    // We have the two Pool balances, but we don't know which one is 'token in' or 'token out'.
                    bytes32 tokenInBalance;
                    bytes32 tokenOutBalance;
                    // In Two Token Pools, token A has a smaller address than token B
                    if (request.tokenIn < request.tokenOut) {
                        // in is A, out is B
                        tokenInBalance = tokenABalance;
                        tokenOutBalance = tokenBBalance;
                    } else {
                        // in is B, out is A
                        tokenOutBalance = tokenABalance;
                        tokenInBalance = tokenBBalance;
                    }
                    // Perform the swap request and compute the new balances for 'token in' and 'token out' after the swap
                    (tokenInBalance, tokenOutBalance, amountCalculated) = _callMinimalSwapInfoPoolOnSwapHook(
                        request,
                        pool,
                        tokenInBalance,
                        tokenOutBalance
                    );
                    // We check the token ordering again to create the new shared cash packed struct
                    poolBalances.sharedCash = request.tokenIn < request.tokenOut
                        ? BalanceAllocation.toSharedCash(tokenInBalance, tokenOutBalance) // in is A, out is B
                        : BalanceAllocation.toSharedCash(tokenOutBalance, tokenInBalance); // in is B, out is A
                }
                function _processMinimalSwapInfoPoolSwapRequest(
                    IPoolSwapStructs.SwapRequest memory request,
                    IMinimalSwapInfoPool pool
                ) private returns (uint256 amountCalculated) {
                    bytes32 tokenInBalance = _getMinimalSwapInfoPoolBalance(request.poolId, request.tokenIn);
                    bytes32 tokenOutBalance = _getMinimalSwapInfoPoolBalance(request.poolId, request.tokenOut);
                    // Perform the swap request and compute the new balances for 'token in' and 'token out' after the swap
                    (tokenInBalance, tokenOutBalance, amountCalculated) = _callMinimalSwapInfoPoolOnSwapHook(
                        request,
                        pool,
                        tokenInBalance,
                        tokenOutBalance
                    );
                    _minimalSwapInfoPoolsBalances[request.poolId][request.tokenIn] = tokenInBalance;
                    _minimalSwapInfoPoolsBalances[request.poolId][request.tokenOut] = tokenOutBalance;
                }
                /**
                 * @dev Calls the onSwap hook for a Pool that implements IMinimalSwapInfoPool: both Minimal Swap Info and Two Token
                 * Pools do this.
                 */
                function _callMinimalSwapInfoPoolOnSwapHook(
                    IPoolSwapStructs.SwapRequest memory request,
                    IMinimalSwapInfoPool pool,
                    bytes32 tokenInBalance,
                    bytes32 tokenOutBalance
                )
                    internal
                    returns (
                        bytes32 newTokenInBalance,
                        bytes32 newTokenOutBalance,
                        uint256 amountCalculated
                    )
                {
                    uint256 tokenInTotal = tokenInBalance.total();
                    uint256 tokenOutTotal = tokenOutBalance.total();
                    request.lastChangeBlock = Math.max(tokenInBalance.lastChangeBlock(), tokenOutBalance.lastChangeBlock());
                    // Perform the swap request callback, and compute the new balances for 'token in' and 'token out' after the swap
                    amountCalculated = pool.onSwap(request, tokenInTotal, tokenOutTotal);
                    (uint256 amountIn, uint256 amountOut) = _getAmounts(request.kind, request.amount, amountCalculated);
                    newTokenInBalance = tokenInBalance.increaseCash(amountIn);
                    newTokenOutBalance = tokenOutBalance.decreaseCash(amountOut);
                }
                function _processGeneralPoolSwapRequest(IPoolSwapStructs.SwapRequest memory request, IGeneralPool pool)
                    private
                    returns (uint256 amountCalculated)
                {
                    bytes32 tokenInBalance;
                    bytes32 tokenOutBalance;
                    // We access both token indexes without checking existence, because we will do it manually immediately after.
                    EnumerableMap.IERC20ToBytes32Map storage poolBalances = _generalPoolsBalances[request.poolId];
                    uint256 indexIn = poolBalances.unchecked_indexOf(request.tokenIn);
                    uint256 indexOut = poolBalances.unchecked_indexOf(request.tokenOut);
                    if (indexIn == 0 || indexOut == 0) {
                        // The tokens might not be registered because the Pool itself is not registered. We check this to provide a
                        // more accurate revert reason.
                        _ensureRegisteredPool(request.poolId);
                        _revert(Errors.TOKEN_NOT_REGISTERED);
                    }
                    // EnumerableMap stores indices *plus one* to use the zero index as a sentinel value - because these are valid,
                    // we can undo this.
                    indexIn -= 1;
                    indexOut -= 1;
                    uint256 tokenAmount = poolBalances.length();
                    uint256[] memory currentBalances = new uint256[](tokenAmount);
                    request.lastChangeBlock = 0;
                    for (uint256 i = 0; i < tokenAmount; i++) {
                        // Because the iteration is bounded by `tokenAmount`, and no tokens are registered or deregistered here, we
                        // know `i` is a valid token index and can use `unchecked_valueAt` to save storage reads.
                        bytes32 balance = poolBalances.unchecked_valueAt(i);
                        currentBalances[i] = balance.total();
                        request.lastChangeBlock = Math.max(request.lastChangeBlock, balance.lastChangeBlock());
                        if (i == indexIn) {
                            tokenInBalance = balance;
                        } else if (i == indexOut) {
                            tokenOutBalance = balance;
                        }
                    }
                    // Perform the swap request callback and compute the new balances for 'token in' and 'token out' after the swap
                    amountCalculated = pool.onSwap(request, currentBalances, indexIn, indexOut);
                    (uint256 amountIn, uint256 amountOut) = _getAmounts(request.kind, request.amount, amountCalculated);
                    tokenInBalance = tokenInBalance.increaseCash(amountIn);
                    tokenOutBalance = tokenOutBalance.decreaseCash(amountOut);
                    // Because no tokens were registered or deregistered between now or when we retrieved the indexes for
                    // 'token in' and 'token out', we can use `unchecked_setAt` to save storage reads.
                    poolBalances.unchecked_setAt(indexIn, tokenInBalance);
                    poolBalances.unchecked_setAt(indexOut, tokenOutBalance);
                }
                // This function is not marked as `nonReentrant` because the underlying mechanism relies on reentrancy
                function queryBatchSwap(
                    SwapKind kind,
                    BatchSwapStep[] memory swaps,
                    IAsset[] memory assets,
                    FundManagement memory funds
                ) external override returns (int256[] memory) {
                    // In order to accurately 'simulate' swaps, this function actually does perform the swaps, including calling the
                    // Pool hooks and updating balances in storage. However, once it computes the final Vault Deltas, it
                    // reverts unconditionally, returning this array as the revert data.
                    //
                    // By wrapping this reverting call, we can decode the deltas 'returned' and return them as a normal Solidity
                    // function would. The only caveat is the function becomes non-view, but off-chain clients can still call it
                    // via eth_call to get the expected result.
                    //
                    // This technique was inspired by the work from the Gnosis team in the Gnosis Safe contract:
                    // https://github.com/gnosis/safe-contracts/blob/v1.2.0/contracts/GnosisSafe.sol#L265
                    //
                    // Most of this function is implemented using inline assembly, as the actual work it needs to do is not
                    // significant, and Solidity is not particularly well-suited to generate this behavior, resulting in a large
                    // amount of generated bytecode.
                    if (msg.sender != address(this)) {
                        // We perform an external call to ourselves, forwarding the same calldata. In this call, the else clause of
                        // the preceding if statement will be executed instead.
                        // solhint-disable-next-line avoid-low-level-calls
                        (bool success, ) = address(this).call(msg.data);
                        // solhint-disable-next-line no-inline-assembly
                        assembly {
                            // This call should always revert to decode the actual asset deltas from the revert reason
                            switch success
                                case 0 {
                                    // Note we are manually writing the memory slot 0. We can safely overwrite whatever is
                                    // stored there as we take full control of the execution and then immediately return.
                                    // We copy the first 4 bytes to check if it matches with the expected signature, otherwise
                                    // there was another revert reason and we should forward it.
                                    returndatacopy(0, 0, 0x04)
                                    let error := and(mload(0), 0xffffffff00000000000000000000000000000000000000000000000000000000)
                                    // If the first 4 bytes don't match with the expected signature, we forward the revert reason.
                                    if eq(eq(error, 0xfa61cc1200000000000000000000000000000000000000000000000000000000), 0) {
                                        returndatacopy(0, 0, returndatasize())
                                        revert(0, returndatasize())
                                    }
                                    // The returndata contains the signature, followed by the raw memory representation of an array:
                                    // length + data. We need to return an ABI-encoded representation of this array.
                                    // An ABI-encoded array contains an additional field when compared to its raw memory
                                    // representation: an offset to the location of the length. The offset itself is 32 bytes long,
                                    // so the smallest value we  can use is 32 for the data to be located immediately after it.
                                    mstore(0, 32)
                                    // We now copy the raw memory array from returndata into memory. Since the offset takes up 32
                                    // bytes, we start copying at address 0x20. We also get rid of the error signature, which takes
                                    // the first four bytes of returndata.
                                    let size := sub(returndatasize(), 0x04)
                                    returndatacopy(0x20, 0x04, size)
                                    // We finally return the ABI-encoded array, which has a total length equal to that of the array
                                    // (returndata), plus the 32 bytes for the offset.
                                    return(0, add(size, 32))
                                }
                                default {
                                    // This call should always revert, but we fail nonetheless if that didn't happen
                                    invalid()
                                }
                        }
                    } else {
                        int256[] memory deltas = _swapWithPools(swaps, assets, funds, kind);
                        // solhint-disable-next-line no-inline-assembly
                        assembly {
                            // We will return a raw representation of the array in memory, which is composed of a 32 byte length,
                            // followed by the 32 byte int256 values. Because revert expects a size in bytes, we multiply the array
                            // length (stored at `deltas`) by 32.
                            let size := mul(mload(deltas), 32)
                            // We send one extra value for the error signature "QueryError(int256[])" which is 0xfa61cc12.
                            // We store it in the previous slot to the `deltas` array. We know there will be at least one available
                            // slot due to how the memory scratch space works.
                            // We can safely overwrite whatever is stored in this slot as we will revert immediately after that.
                            mstore(sub(deltas, 0x20), 0x00000000000000000000000000000000000000000000000000000000fa61cc12)
                            let start := sub(deltas, 0x04)
                            // When copying from `deltas` into returndata, we copy an additional 36 bytes to also return the array's
                            // length and the error signature.
                            revert(start, add(size, 36))
                        }
                    }
                }
            }
            // SPDX-License-Identifier: MIT
            pragma solidity ^0.7.0;
            /**
             * @dev Interface of the ERC20 standard as defined in the EIP.
             */
            interface IERC20 {
                /**
                 * @dev Returns the amount of tokens in existence.
                 */
                function totalSupply() external view returns (uint256);
                /**
                 * @dev Returns the amount of tokens owned by `account`.
                 */
                function balanceOf(address account) external view returns (uint256);
                /**
                 * @dev Moves `amount` tokens from the caller's account to `recipient`.
                 *
                 * Returns a boolean value indicating whether the operation succeeded.
                 *
                 * Emits a {Transfer} event.
                 */
                function transfer(address recipient, uint256 amount) external returns (bool);
                /**
                 * @dev Returns the remaining number of tokens that `spender` will be
                 * allowed to spend on behalf of `owner` through {transferFrom}. This is
                 * zero by default.
                 *
                 * This value changes when {approve} or {transferFrom} are called.
                 */
                function allowance(address owner, address spender) external view returns (uint256);
                /**
                 * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
                 *
                 * Returns a boolean value indicating whether the operation succeeded.
                 *
                 * IMPORTANT: Beware that changing an allowance with this method brings the risk
                 * that someone may use both the old and the new allowance by unfortunate
                 * transaction ordering. One possible solution to mitigate this race
                 * condition is to first reduce the spender's allowance to 0 and set the
                 * desired value afterwards:
                 * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
                 *
                 * Emits an {Approval} event.
                 */
                function approve(address spender, uint256 amount) external returns (bool);
                /**
                 * @dev Moves `amount` tokens from `sender` to `recipient` using the
                 * allowance mechanism. `amount` is then deducted from the caller's
                 * allowance.
                 *
                 * Returns a boolean value indicating whether the operation succeeded.
                 *
                 * Emits a {Transfer} event.
                 */
                function transferFrom(
                    address sender,
                    address recipient,
                    uint256 amount
                ) external returns (bool);
                /**
                 * @dev Emitted when `value` tokens are moved from one account (`from`) to
                 * another (`to`).
                 *
                 * Note that `value` may be zero.
                 */
                event Transfer(address indexed from, address indexed to, uint256 value);
                /**
                 * @dev Emitted when the allowance of a `spender` for an `owner` is set by
                 * a call to {approve}. `value` is the new allowance.
                 */
                event Approval(address indexed owner, address indexed spender, uint256 value);
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            // solhint-disable
            /**
             * @dev Reverts if `condition` is false, with a revert reason containing `errorCode`. Only codes up to 999 are
             * supported.
             */
            function _require(bool condition, uint256 errorCode) pure {
                if (!condition) _revert(errorCode);
            }
            /**
             * @dev Reverts with a revert reason containing `errorCode`. Only codes up to 999 are supported.
             */
            function _revert(uint256 errorCode) pure {
                // We're going to dynamically create a revert string based on the error code, with the following format:
                // 'BAL#{errorCode}'
                // where the code is left-padded with zeroes to three digits (so they range from 000 to 999).
                //
                // We don't have revert strings embedded in the contract to save bytecode size: it takes much less space to store a
                // number (8 to 16 bits) than the individual string characters.
                //
                // The dynamic string creation algorithm that follows could be implemented in Solidity, but assembly allows for a
                // much denser implementation, again saving bytecode size. Given this function unconditionally reverts, this is a
                // safe place to rely on it without worrying about how its usage might affect e.g. memory contents.
                assembly {
                    // First, we need to compute the ASCII representation of the error code. We assume that it is in the 0-999
                    // range, so we only need to convert three digits. To convert the digits to ASCII, we add 0x30, the value for
                    // the '0' character.
                    let units := add(mod(errorCode, 10), 0x30)
                    errorCode := div(errorCode, 10)
                    let tenths := add(mod(errorCode, 10), 0x30)
                    errorCode := div(errorCode, 10)
                    let hundreds := add(mod(errorCode, 10), 0x30)
                    // With the individual characters, we can now construct the full string. The "BAL#" part is a known constant
                    // (0x42414c23): we simply shift this by 24 (to provide space for the 3 bytes of the error code), and add the
                    // characters to it, each shifted by a multiple of 8.
                    // The revert reason is then shifted left by 200 bits (256 minus the length of the string, 7 characters * 8 bits
                    // per character = 56) to locate it in the most significant part of the 256 slot (the beginning of a byte
                    // array).
                    let revertReason := shl(200, add(0x42414c23000000, add(add(units, shl(8, tenths)), shl(16, hundreds))))
                    // We can now encode the reason in memory, which can be safely overwritten as we're about to revert. The encoded
                    // message will have the following layout:
                    // [ revert reason identifier ] [ string location offset ] [ string length ] [ string contents ]
                    // The Solidity revert reason identifier is 0x08c739a0, the function selector of the Error(string) function. We
                    // also write zeroes to the next 28 bytes of memory, but those are about to be overwritten.
                    mstore(0x0, 0x08c379a000000000000000000000000000000000000000000000000000000000)
                    // Next is the offset to the location of the string, which will be placed immediately after (20 bytes away).
                    mstore(0x04, 0x0000000000000000000000000000000000000000000000000000000000000020)
                    // The string length is fixed: 7 characters.
                    mstore(0x24, 7)
                    // Finally, the string itself is stored.
                    mstore(0x44, revertReason)
                    // Even if the string is only 7 bytes long, we need to return a full 32 byte slot containing it. The length of
                    // the encoded message is therefore 4 + 32 + 32 + 32 = 100.
                    revert(0, 100)
                }
            }
            library Errors {
                // Math
                uint256 internal constant ADD_OVERFLOW = 0;
                uint256 internal constant SUB_OVERFLOW = 1;
                uint256 internal constant SUB_UNDERFLOW = 2;
                uint256 internal constant MUL_OVERFLOW = 3;
                uint256 internal constant ZERO_DIVISION = 4;
                uint256 internal constant DIV_INTERNAL = 5;
                uint256 internal constant X_OUT_OF_BOUNDS = 6;
                uint256 internal constant Y_OUT_OF_BOUNDS = 7;
                uint256 internal constant PRODUCT_OUT_OF_BOUNDS = 8;
                uint256 internal constant INVALID_EXPONENT = 9;
                // Input
                uint256 internal constant OUT_OF_BOUNDS = 100;
                uint256 internal constant UNSORTED_ARRAY = 101;
                uint256 internal constant UNSORTED_TOKENS = 102;
                uint256 internal constant INPUT_LENGTH_MISMATCH = 103;
                uint256 internal constant ZERO_TOKEN = 104;
                // Shared pools
                uint256 internal constant MIN_TOKENS = 200;
                uint256 internal constant MAX_TOKENS = 201;
                uint256 internal constant MAX_SWAP_FEE_PERCENTAGE = 202;
                uint256 internal constant MIN_SWAP_FEE_PERCENTAGE = 203;
                uint256 internal constant MINIMUM_BPT = 204;
                uint256 internal constant CALLER_NOT_VAULT = 205;
                uint256 internal constant UNINITIALIZED = 206;
                uint256 internal constant BPT_IN_MAX_AMOUNT = 207;
                uint256 internal constant BPT_OUT_MIN_AMOUNT = 208;
                uint256 internal constant EXPIRED_PERMIT = 209;
                // Pools
                uint256 internal constant MIN_AMP = 300;
                uint256 internal constant MAX_AMP = 301;
                uint256 internal constant MIN_WEIGHT = 302;
                uint256 internal constant MAX_STABLE_TOKENS = 303;
                uint256 internal constant MAX_IN_RATIO = 304;
                uint256 internal constant MAX_OUT_RATIO = 305;
                uint256 internal constant MIN_BPT_IN_FOR_TOKEN_OUT = 306;
                uint256 internal constant MAX_OUT_BPT_FOR_TOKEN_IN = 307;
                uint256 internal constant NORMALIZED_WEIGHT_INVARIANT = 308;
                uint256 internal constant INVALID_TOKEN = 309;
                uint256 internal constant UNHANDLED_JOIN_KIND = 310;
                uint256 internal constant ZERO_INVARIANT = 311;
                // Lib
                uint256 internal constant REENTRANCY = 400;
                uint256 internal constant SENDER_NOT_ALLOWED = 401;
                uint256 internal constant PAUSED = 402;
                uint256 internal constant PAUSE_WINDOW_EXPIRED = 403;
                uint256 internal constant MAX_PAUSE_WINDOW_DURATION = 404;
                uint256 internal constant MAX_BUFFER_PERIOD_DURATION = 405;
                uint256 internal constant INSUFFICIENT_BALANCE = 406;
                uint256 internal constant INSUFFICIENT_ALLOWANCE = 407;
                uint256 internal constant ERC20_TRANSFER_FROM_ZERO_ADDRESS = 408;
                uint256 internal constant ERC20_TRANSFER_TO_ZERO_ADDRESS = 409;
                uint256 internal constant ERC20_MINT_TO_ZERO_ADDRESS = 410;
                uint256 internal constant ERC20_BURN_FROM_ZERO_ADDRESS = 411;
                uint256 internal constant ERC20_APPROVE_FROM_ZERO_ADDRESS = 412;
                uint256 internal constant ERC20_APPROVE_TO_ZERO_ADDRESS = 413;
                uint256 internal constant ERC20_TRANSFER_EXCEEDS_ALLOWANCE = 414;
                uint256 internal constant ERC20_DECREASED_ALLOWANCE_BELOW_ZERO = 415;
                uint256 internal constant ERC20_TRANSFER_EXCEEDS_BALANCE = 416;
                uint256 internal constant ERC20_BURN_EXCEEDS_ALLOWANCE = 417;
                uint256 internal constant SAFE_ERC20_CALL_FAILED = 418;
                uint256 internal constant ADDRESS_INSUFFICIENT_BALANCE = 419;
                uint256 internal constant ADDRESS_CANNOT_SEND_VALUE = 420;
                uint256 internal constant SAFE_CAST_VALUE_CANT_FIT_INT256 = 421;
                uint256 internal constant GRANT_SENDER_NOT_ADMIN = 422;
                uint256 internal constant REVOKE_SENDER_NOT_ADMIN = 423;
                uint256 internal constant RENOUNCE_SENDER_NOT_ALLOWED = 424;
                uint256 internal constant BUFFER_PERIOD_EXPIRED = 425;
                // Vault
                uint256 internal constant INVALID_POOL_ID = 500;
                uint256 internal constant CALLER_NOT_POOL = 501;
                uint256 internal constant SENDER_NOT_ASSET_MANAGER = 502;
                uint256 internal constant USER_DOESNT_ALLOW_RELAYER = 503;
                uint256 internal constant INVALID_SIGNATURE = 504;
                uint256 internal constant EXIT_BELOW_MIN = 505;
                uint256 internal constant JOIN_ABOVE_MAX = 506;
                uint256 internal constant SWAP_LIMIT = 507;
                uint256 internal constant SWAP_DEADLINE = 508;
                uint256 internal constant CANNOT_SWAP_SAME_TOKEN = 509;
                uint256 internal constant UNKNOWN_AMOUNT_IN_FIRST_SWAP = 510;
                uint256 internal constant MALCONSTRUCTED_MULTIHOP_SWAP = 511;
                uint256 internal constant INTERNAL_BALANCE_OVERFLOW = 512;
                uint256 internal constant INSUFFICIENT_INTERNAL_BALANCE = 513;
                uint256 internal constant INVALID_ETH_INTERNAL_BALANCE = 514;
                uint256 internal constant INVALID_POST_LOAN_BALANCE = 515;
                uint256 internal constant INSUFFICIENT_ETH = 516;
                uint256 internal constant UNALLOCATED_ETH = 517;
                uint256 internal constant ETH_TRANSFER = 518;
                uint256 internal constant CANNOT_USE_ETH_SENTINEL = 519;
                uint256 internal constant TOKENS_MISMATCH = 520;
                uint256 internal constant TOKEN_NOT_REGISTERED = 521;
                uint256 internal constant TOKEN_ALREADY_REGISTERED = 522;
                uint256 internal constant TOKENS_ALREADY_SET = 523;
                uint256 internal constant TOKENS_LENGTH_MUST_BE_2 = 524;
                uint256 internal constant NONZERO_TOKEN_BALANCE = 525;
                uint256 internal constant BALANCE_TOTAL_OVERFLOW = 526;
                uint256 internal constant POOL_NO_TOKENS = 527;
                uint256 internal constant INSUFFICIENT_FLASH_LOAN_BALANCE = 528;
                // Fees
                uint256 internal constant SWAP_FEE_PERCENTAGE_TOO_HIGH = 600;
                uint256 internal constant FLASH_LOAN_FEE_PERCENTAGE_TOO_HIGH = 601;
                uint256 internal constant INSUFFICIENT_FLASH_LOAN_FEE_AMOUNT = 602;
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            import "./BalancerErrors.sol";
            import "./IAuthentication.sol";
            /**
             * @dev Building block for performing access control on external functions.
             *
             * This contract is used via the `authenticate` modifier (or the `_authenticateCaller` function), which can be applied
             * to external functions to only make them callable by authorized accounts.
             *
             * Derived contracts must implement the `_canPerform` function, which holds the actual access control logic.
             */
            abstract contract Authentication is IAuthentication {
                bytes32 private immutable _actionIdDisambiguator;
                /**
                 * @dev The main purpose of the `actionIdDisambiguator` is to prevent accidental function selector collisions in
                 * multi contract systems.
                 *
                 * There are two main uses for it:
                 *  - if the contract is a singleton, any unique identifier can be used to make the associated action identifiers
                 *    unique. The contract's own address is a good option.
                 *  - if the contract belongs to a family that shares action identifiers for the same functions, an identifier
                 *    shared by the entire family (and no other contract) should be used instead.
                 */
                constructor(bytes32 actionIdDisambiguator) {
                    _actionIdDisambiguator = actionIdDisambiguator;
                }
                /**
                 * @dev Reverts unless the caller is allowed to call this function. Should only be applied to external functions.
                 */
                modifier authenticate() {
                    _authenticateCaller();
                    _;
                }
                /**
                 * @dev Reverts unless the caller is allowed to call the entry point function.
                 */
                function _authenticateCaller() internal view {
                    bytes32 actionId = getActionId(msg.sig);
                    _require(_canPerform(actionId, msg.sender), Errors.SENDER_NOT_ALLOWED);
                }
                function getActionId(bytes4 selector) public view override returns (bytes32) {
                    // Each external function is dynamically assigned an action identifier as the hash of the disambiguator and the
                    // function selector. Disambiguation is necessary to avoid potential collisions in the function selectors of
                    // multiple contracts.
                    return keccak256(abi.encodePacked(_actionIdDisambiguator, selector));
                }
                function _canPerform(bytes32 actionId, address user) internal view virtual returns (bool);
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            import "./BalancerErrors.sol";
            import "./ITemporarilyPausable.sol";
            /**
             * @dev Allows for a contract to be paused during an initial period after deployment, disabling functionality. Can be
             * used as an emergency switch in case a security vulnerability or threat is identified.
             *
             * The contract can only be paused during the Pause Window, a period that starts at deployment. It can also be
             * unpaused and repaused any number of times during this period. This is intended to serve as a safety measure: it lets
             * system managers react quickly to potentially dangerous situations, knowing that this action is reversible if careful
             * analysis later determines there was a false alarm.
             *
             * If the contract is paused when the Pause Window finishes, it will remain in the paused state through an additional
             * Buffer Period, after which it will be automatically unpaused forever. This is to ensure there is always enough time
             * to react to an emergency, even if the threat is discovered shortly before the Pause Window expires.
             *
             * Note that since the contract can only be paused within the Pause Window, unpausing during the Buffer Period is
             * irreversible.
             */
            abstract contract TemporarilyPausable is ITemporarilyPausable {
                // The Pause Window and Buffer Period are timestamp-based: they should not be relied upon for sub-minute accuracy.
                // solhint-disable not-rely-on-time
                uint256 private constant _MAX_PAUSE_WINDOW_DURATION = 90 days;
                uint256 private constant _MAX_BUFFER_PERIOD_DURATION = 30 days;
                uint256 private immutable _pauseWindowEndTime;
                uint256 private immutable _bufferPeriodEndTime;
                bool private _paused;
                constructor(uint256 pauseWindowDuration, uint256 bufferPeriodDuration) {
                    _require(pauseWindowDuration <= _MAX_PAUSE_WINDOW_DURATION, Errors.MAX_PAUSE_WINDOW_DURATION);
                    _require(bufferPeriodDuration <= _MAX_BUFFER_PERIOD_DURATION, Errors.MAX_BUFFER_PERIOD_DURATION);
                    uint256 pauseWindowEndTime = block.timestamp + pauseWindowDuration;
                    _pauseWindowEndTime = pauseWindowEndTime;
                    _bufferPeriodEndTime = pauseWindowEndTime + bufferPeriodDuration;
                }
                /**
                 * @dev Reverts if the contract is paused.
                 */
                modifier whenNotPaused() {
                    _ensureNotPaused();
                    _;
                }
                /**
                 * @dev Returns the current contract pause status, as well as the end times of the Pause Window and Buffer
                 * Period.
                 */
                function getPausedState()
                    external
                    view
                    override
                    returns (
                        bool paused,
                        uint256 pauseWindowEndTime,
                        uint256 bufferPeriodEndTime
                    )
                {
                    paused = !_isNotPaused();
                    pauseWindowEndTime = _getPauseWindowEndTime();
                    bufferPeriodEndTime = _getBufferPeriodEndTime();
                }
                /**
                 * @dev Sets the pause state to `paused`. The contract can only be paused until the end of the Pause Window, and
                 * unpaused until the end of the Buffer Period.
                 *
                 * Once the Buffer Period expires, this function reverts unconditionally.
                 */
                function _setPaused(bool paused) internal {
                    if (paused) {
                        _require(block.timestamp < _getPauseWindowEndTime(), Errors.PAUSE_WINDOW_EXPIRED);
                    } else {
                        _require(block.timestamp < _getBufferPeriodEndTime(), Errors.BUFFER_PERIOD_EXPIRED);
                    }
                    _paused = paused;
                    emit PausedStateChanged(paused);
                }
                /**
                 * @dev Reverts if the contract is paused.
                 */
                function _ensureNotPaused() internal view {
                    _require(_isNotPaused(), Errors.PAUSED);
                }
                /**
                 * @dev Returns true if the contract is unpaused.
                 *
                 * Once the Buffer Period expires, the gas cost of calling this function is reduced dramatically, as storage is no
                 * longer accessed.
                 */
                function _isNotPaused() internal view returns (bool) {
                    // After the Buffer Period, the (inexpensive) timestamp check short-circuits the storage access.
                    return block.timestamp > _getBufferPeriodEndTime() || !_paused;
                }
                // These getters lead to reduced bytecode size by inlining the immutable variables in a single place.
                function _getPauseWindowEndTime() private view returns (uint256) {
                    return _pauseWindowEndTime;
                }
                function _getBufferPeriodEndTime() private view returns (uint256) {
                    return _bufferPeriodEndTime;
                }
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            import "./BalancerErrors.sol";
            import "./ISignaturesValidator.sol";
            import "../openzeppelin/EIP712.sol";
            /**
             * @dev Utility for signing Solidity function calls.
             *
             * This contract relies on the fact that Solidity contracts can be called with extra calldata, and enables
             * meta-transaction schemes by appending an EIP712 signature of the original calldata at the end.
             *
             * Derived contracts must implement the `_typeHash` function to map function selectors to EIP712 structs.
             */
            abstract contract SignaturesValidator is ISignaturesValidator, EIP712 {
                // The appended data consists of a deadline, plus the [v,r,s] signature. For simplicity, we use a full 256 bit slot
                // for each of these values, even if 'v' is typically an 8 bit value.
                uint256 internal constant _EXTRA_CALLDATA_LENGTH = 4 * 32;
                // Replay attack prevention for each user.
                mapping(address => uint256) internal _nextNonce;
                constructor(string memory name) EIP712(name, "1") {
                    // solhint-disable-previous-line no-empty-blocks
                }
                function getDomainSeparator() external view override returns (bytes32) {
                    return _domainSeparatorV4();
                }
                function getNextNonce(address user) external view override returns (uint256) {
                    return _nextNonce[user];
                }
                /**
                 * @dev Reverts with `errorCode` unless a valid signature for `user` was appended to the calldata.
                 */
                function _validateSignature(address user, uint256 errorCode) internal {
                    uint256 nextNonce = _nextNonce[user]++;
                    _require(_isSignatureValid(user, nextNonce), errorCode);
                }
                function _isSignatureValid(address user, uint256 nonce) private view returns (bool) {
                    uint256 deadline = _deadline();
                    // The deadline is timestamp-based: it should not be relied upon for sub-minute accuracy.
                    // solhint-disable-next-line not-rely-on-time
                    if (deadline < block.timestamp) {
                        return false;
                    }
                    bytes32 typeHash = _typeHash();
                    if (typeHash == bytes32(0)) {
                        // Prevent accidental signature validation for functions that don't have an associated type hash.
                        return false;
                    }
                    // All type hashes have this format: (bytes calldata, address sender, uint256 nonce, uint256 deadline).
                    bytes32 structHash = keccak256(abi.encode(typeHash, keccak256(_calldata()), msg.sender, nonce, deadline));
                    bytes32 digest = _hashTypedDataV4(structHash);
                    (uint8 v, bytes32 r, bytes32 s) = _signature();
                    address recoveredAddress = ecrecover(digest, v, r, s);
                    // ecrecover returns the zero address on recover failure, so we need to handle that explicitly.
                    return recoveredAddress != address(0) && recoveredAddress == user;
                }
                /**
                 * @dev Returns the EIP712 type hash for the current entry point function, which can be identified by its function
                 * selector (available as `msg.sig`).
                 *
                 * The type hash must conform to the following format:
                 *  <name>(bytes calldata, address sender, uint256 nonce, uint256 deadline)
                 *
                 * If 0x00, all signatures will be considered invalid.
                 */
                function _typeHash() internal view virtual returns (bytes32);
                /**
                 * @dev Extracts the signature deadline from extra calldata.
                 *
                 * This function returns bogus data if no signature is included.
                 */
                function _deadline() internal pure returns (uint256) {
                    // The deadline is the first extra argument at the end of the original calldata.
                    return uint256(_decodeExtraCalldataWord(0));
                }
                /**
                 * @dev Extracts the signature parameters from extra calldata.
                 *
                 * This function returns bogus data if no signature is included. This is not a security risk, as that data would not
                 * be considered a valid signature in the first place.
                 */
                function _signature()
                    internal
                    pure
                    returns (
                        uint8 v,
                        bytes32 r,
                        bytes32 s
                    )
                {
                    // v, r and s are appended after the signature deadline, in that order.
                    v = uint8(uint256(_decodeExtraCalldataWord(0x20)));
                    r = _decodeExtraCalldataWord(0x40);
                    s = _decodeExtraCalldataWord(0x60);
                }
                /**
                 * @dev Returns the original calldata, without the extra bytes containing the signature.
                 *
                 * This function returns bogus data if no signature is included.
                 */
                function _calldata() internal pure returns (bytes memory result) {
                    result = msg.data; // A calldata to memory assignment results in memory allocation and copy of contents.
                    if (result.length > _EXTRA_CALLDATA_LENGTH) {
                        // solhint-disable-next-line no-inline-assembly
                        assembly {
                            // We simply overwrite the array length with the reduced one.
                            mstore(result, sub(calldatasize(), _EXTRA_CALLDATA_LENGTH))
                        }
                    }
                }
                /**
                 * @dev Returns a 256 bit word from 'extra' calldata, at some offset from the expected end of the original calldata.
                 *
                 * This function returns bogus data if no signature is included.
                 */
                function _decodeExtraCalldataWord(uint256 offset) private pure returns (bytes32 result) {
                    // solhint-disable-next-line no-inline-assembly
                    assembly {
                        result := calldataload(add(sub(calldatasize(), _EXTRA_CALLDATA_LENGTH), offset))
                    }
                }
            }
            // SPDX-License-Identifier: MIT
            pragma solidity ^0.7.0;
            import "../helpers/BalancerErrors.sol";
            // Based on the ReentrancyGuard library from OpenZeppelin contracts, altered to reduce bytecode size.
            // Modifier code is inlined by the compiler, which causes its code to appear multiple times in the codebase. By using
            // private functions, we achieve the same end result with slightly higher runtime gas costs but reduced bytecode size.
            /**
             * @dev Contract module that helps prevent reentrant calls to a function.
             *
             * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
             * available, which can be applied to functions to make sure there are no nested
             * (reentrant) calls to them.
             *
             * Note that because there is a single `nonReentrant` guard, functions marked as
             * `nonReentrant` may not call one another. This can be worked around by making
             * those functions `private`, and then adding `external` `nonReentrant` entry
             * points to them.
             *
             * TIP: If you would like to learn more about reentrancy and alternative ways
             * to protect against it, check out our blog post
             * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
             */
            abstract contract ReentrancyGuard {
                // Booleans are more expensive than uint256 or any type that takes up a full
                // word because each write operation emits an extra SLOAD to first read the
                // slot's contents, replace the bits taken up by the boolean, and then write
                // back. This is the compiler's defense against contract upgrades and
                // pointer aliasing, and it cannot be disabled.
                // The values being non-zero value makes deployment a bit more expensive,
                // but in exchange the refund on every call to nonReentrant will be lower in
                // amount. Since refunds are capped to a percentage of the total
                // transaction's gas, it is best to keep them low in cases like this one, to
                // increase the likelihood of the full refund coming into effect.
                uint256 private constant _NOT_ENTERED = 1;
                uint256 private constant _ENTERED = 2;
                uint256 private _status;
                constructor() {
                    _status = _NOT_ENTERED;
                }
                /**
                 * @dev Prevents a contract from calling itself, directly or indirectly.
                 * Calling a `nonReentrant` function from another `nonReentrant`
                 * function is not supported. It is possible to prevent this from happening
                 * by making the `nonReentrant` function external, and make it call a
                 * `private` function that does the actual work.
                 */
                modifier nonReentrant() {
                    _enterNonReentrant();
                    _;
                    _exitNonReentrant();
                }
                function _enterNonReentrant() private {
                    // On the first call to nonReentrant, _status will be _NOT_ENTERED
                    _require(_status != _ENTERED, Errors.REENTRANCY);
                    // Any calls to nonReentrant after this point will fail
                    _status = _ENTERED;
                }
                function _exitNonReentrant() private {
                    // By storing the original value once again, a refund is triggered (see
                    // https://eips.ethereum.org/EIPS/eip-2200)
                    _status = _NOT_ENTERED;
                }
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma experimental ABIEncoderV2;
            import "../../lib/openzeppelin/IERC20.sol";
            import "./IWETH.sol";
            import "./IAsset.sol";
            import "./IAuthorizer.sol";
            import "./IFlashLoanRecipient.sol";
            import "../ProtocolFeesCollector.sol";
            import "../../lib/helpers/ISignaturesValidator.sol";
            import "../../lib/helpers/ITemporarilyPausable.sol";
            pragma solidity ^0.7.0;
            /**
             * @dev Full external interface for the Vault core contract - no external or public methods exist in the contract that
             * don't override one of these declarations.
             */
            interface IVault is ISignaturesValidator, ITemporarilyPausable {
                // Generalities about the Vault:
                //
                // - Whenever documentation refers to 'tokens', it strictly refers to ERC20-compliant token contracts. Tokens are
                // transferred out of the Vault by calling the `IERC20.transfer` function, and transferred in by calling
                // `IERC20.transferFrom`. In these cases, the sender must have previously allowed the Vault to use their tokens by
                // calling `IERC20.approve`. The only deviation from the ERC20 standard that is supported is functions not returning
                // a boolean value: in these scenarios, a non-reverting call is assumed to be successful.
                //
                // - All non-view functions in the Vault are non-reentrant: calling them while another one is mid-execution (e.g.
                // while execution control is transferred to a token contract during a swap) will result in a revert. View
                // functions can be called in a re-reentrant way, but doing so might cause them to return inconsistent results.
                // Contracts calling view functions in the Vault must make sure the Vault has not already been entered.
                //
                // - View functions revert if referring to either unregistered Pools, or unregistered tokens for registered Pools.
                // Authorizer
                //
                // Some system actions are permissioned, like setting and collecting protocol fees. This permissioning system exists
                // outside of the Vault in the Authorizer contract: the Vault simply calls the Authorizer to check if the caller
                // can perform a given action.
                /**
                 * @dev Returns the Vault's Authorizer.
                 */
                function getAuthorizer() external view returns (IAuthorizer);
                /**
                 * @dev Sets a new Authorizer for the Vault. The caller must be allowed by the current Authorizer to do this.
                 *
                 * Emits an `AuthorizerChanged` event.
                 */
                function setAuthorizer(IAuthorizer newAuthorizer) external;
                /**
                 * @dev Emitted when a new authorizer is set by `setAuthorizer`.
                 */
                event AuthorizerChanged(IAuthorizer indexed newAuthorizer);
                // Relayers
                //
                // Additionally, it is possible for an account to perform certain actions on behalf of another one, using their
                // Vault ERC20 allowance and Internal Balance. These accounts are said to be 'relayers' for these Vault functions,
                // and are expected to be smart contracts with sound authentication mechanisms. For an account to be able to wield
                // this power, two things must occur:
                //  - The Authorizer must grant the account the permission to be a relayer for the relevant Vault function. This
                //    means that Balancer governance must approve each individual contract to act as a relayer for the intended
                //    functions.
                //  - Each user must approve the relayer to act on their behalf.
                // This double protection means users cannot be tricked into approving malicious relayers (because they will not
                // have been allowed by the Authorizer via governance), nor can malicious relayers approved by a compromised
                // Authorizer or governance drain user funds, since they would also need to be approved by each individual user.
                /**
                 * @dev Returns true if `user` has approved `relayer` to act as a relayer for them.
                 */
                function hasApprovedRelayer(address user, address relayer) external view returns (bool);
                /**
                 * @dev Allows `relayer` to act as a relayer for `sender` if `approved` is true, and disallows it otherwise.
                 *
                 * Emits a `RelayerApprovalChanged` event.
                 */
                function setRelayerApproval(
                    address sender,
                    address relayer,
                    bool approved
                ) external;
                /**
                 * @dev Emitted every time a relayer is approved or disapproved by `setRelayerApproval`.
                 */
                event RelayerApprovalChanged(address indexed relayer, address indexed sender, bool approved);
                // Internal Balance
                //
                // Users can deposit tokens into the Vault, where they are allocated to their Internal Balance, and later
                // transferred or withdrawn. It can also be used as a source of tokens when joining Pools, as a destination
                // when exiting them, and as either when performing swaps. This usage of Internal Balance results in greatly reduced
                // gas costs when compared to relying on plain ERC20 transfers, leading to large savings for frequent users.
                //
                // Internal Balance management features batching, which means a single contract call can be used to perform multiple
                // operations of different kinds, with different senders and recipients, at once.
                /**
                 * @dev Returns `user`'s Internal Balance for a set of tokens.
                 */
                function getInternalBalance(address user, IERC20[] memory tokens) external view returns (uint256[] memory);
                /**
                 * @dev Performs a set of user balance operations, which involve Internal Balance (deposit, withdraw or transfer)
                 * and plain ERC20 transfers using the Vault's allowance. This last feature is particularly useful for relayers, as
                 * it lets integrators reuse a user's Vault allowance.
                 *
                 * For each operation, if the caller is not `sender`, it must be an authorized relayer for them.
                 */
                function manageUserBalance(UserBalanceOp[] memory ops) external payable;
                /**
                 * @dev Data for `manageUserBalance` operations, which include the possibility for ETH to be sent and received
                 without manual WETH wrapping or unwrapping.
                 */
                struct UserBalanceOp {
                    UserBalanceOpKind kind;
                    IAsset asset;
                    uint256 amount;
                    address sender;
                    address payable recipient;
                }
                // There are four possible operations in `manageUserBalance`:
                //
                // - DEPOSIT_INTERNAL
                // Increases the Internal Balance of the `recipient` account by transferring tokens from the corresponding
                // `sender`. The sender must have allowed the Vault to use their tokens via `IERC20.approve()`.
                //
                // ETH can be used by passing the ETH sentinel value as the asset and forwarding ETH in the call: it will be wrapped
                // and deposited as WETH. Any ETH amount remaining will be sent back to the caller (not the sender, which is
                // relevant for relayers).
                //
                // Emits an `InternalBalanceChanged` event.
                //
                //
                // - WITHDRAW_INTERNAL
                // Decreases the Internal Balance of the `sender` account by transferring tokens to the `recipient`.
                //
                // ETH can be used by passing the ETH sentinel value as the asset. This will deduct WETH instead, unwrap it and send
                // it to the recipient as ETH.
                //
                // Emits an `InternalBalanceChanged` event.
                //
                //
                // - TRANSFER_INTERNAL
                // Transfers tokens from the Internal Balance of the `sender` account to the Internal Balance of `recipient`.
                //
                // Reverts if the ETH sentinel value is passed.
                //
                // Emits an `InternalBalanceChanged` event.
                //
                //
                // - TRANSFER_EXTERNAL
                // Transfers tokens from `sender` to `recipient`, using the Vault's ERC20 allowance. This is typically used by
                // relayers, as it lets them reuse a user's Vault allowance.
                //
                // Reverts if the ETH sentinel value is passed.
                //
                // Emits an `ExternalBalanceTransfer` event.
                enum UserBalanceOpKind { DEPOSIT_INTERNAL, WITHDRAW_INTERNAL, TRANSFER_INTERNAL, TRANSFER_EXTERNAL }
                /**
                 * @dev Emitted when a user's Internal Balance changes, either from calls to `manageUserBalance`, or through
                 * interacting with Pools using Internal Balance.
                 *
                 * Because Internal Balance works exclusively with ERC20 tokens, ETH deposits and withdrawals will use the WETH
                 * address.
                 */
                event InternalBalanceChanged(address indexed user, IERC20 indexed token, int256 delta);
                /**
                 * @dev Emitted when a user's Vault ERC20 allowance is used by the Vault to transfer tokens to an external account.
                 */
                event ExternalBalanceTransfer(IERC20 indexed token, address indexed sender, address recipient, uint256 amount);
                // Pools
                //
                // There are three specialization settings for Pools, which allow for cheaper swaps at the cost of reduced
                // functionality:
                //
                //  - General: no specialization, suited for all Pools. IGeneralPool is used for swap request callbacks, passing the
                // balance of all tokens in the Pool. These Pools have the largest swap costs (because of the extra storage reads),
                // which increase with the number of registered tokens.
                //
                //  - Minimal Swap Info: IMinimalSwapInfoPool is used instead of IGeneralPool, which saves gas by only passing the
                // balance of the two tokens involved in the swap. This is suitable for some pricing algorithms, like the weighted
                // constant product one popularized by Balancer V1. Swap costs are smaller compared to general Pools, and are
                // independent of the number of registered tokens.
                //
                //  - Two Token: only allows two tokens to be registered. This achieves the lowest possible swap gas cost. Like
                // minimal swap info Pools, these are called via IMinimalSwapInfoPool.
                enum PoolSpecialization { GENERAL, MINIMAL_SWAP_INFO, TWO_TOKEN }
                /**
                 * @dev Registers the caller account as a Pool with a given specialization setting. Returns the Pool's ID, which
                 * is used in all Pool-related functions. Pools cannot be deregistered, nor can the Pool's specialization be
                 * changed.
                 *
                 * The caller is expected to be a smart contract that implements either `IGeneralPool` or `IMinimalSwapInfoPool`,
                 * depending on the chosen specialization setting. This contract is known as the Pool's contract.
                 *
                 * Note that the same contract may register itself as multiple Pools with unique Pool IDs, or in other words,
                 * multiple Pools may share the same contract.
                 *
                 * Emits a `PoolRegistered` event.
                 */
                function registerPool(PoolSpecialization specialization) external returns (bytes32);
                /**
                 * @dev Emitted when a Pool is registered by calling `registerPool`.
                 */
                event PoolRegistered(bytes32 indexed poolId, address indexed poolAddress, PoolSpecialization specialization);
                /**
                 * @dev Returns a Pool's contract address and specialization setting.
                 */
                function getPool(bytes32 poolId) external view returns (address, PoolSpecialization);
                /**
                 * @dev Registers `tokens` for the `poolId` Pool. Must be called by the Pool's contract.
                 *
                 * Pools can only interact with tokens they have registered. Users join a Pool by transferring registered tokens,
                 * exit by receiving registered tokens, and can only swap registered tokens.
                 *
                 * Each token can only be registered once. For Pools with the Two Token specialization, `tokens` must have a length
                 * of two, that is, both tokens must be registered in the same `registerTokens` call, and they must be sorted in
                 * ascending order.
                 *
                 * The `tokens` and `assetManagers` arrays must have the same length, and each entry in these indicates the Asset
                 * Manager for the corresponding token. Asset Managers can manage a Pool's tokens via `managePoolBalance`,
                 * depositing and withdrawing them directly, and can even set their balance to arbitrary amounts. They are therefore
                 * expected to be highly secured smart contracts with sound design principles, and the decision to register an
                 * Asset Manager should not be made lightly.
                 *
                 * Pools can choose not to assign an Asset Manager to a given token by passing in the zero address. Once an Asset
                 * Manager is set, it cannot be changed except by deregistering the associated token and registering again with a
                 * different Asset Manager.
                 *
                 * Emits a `TokensRegistered` event.
                 */
                function registerTokens(
                    bytes32 poolId,
                    IERC20[] memory tokens,
                    address[] memory assetManagers
                ) external;
                /**
                 * @dev Emitted when a Pool registers tokens by calling `registerTokens`.
                 */
                event TokensRegistered(bytes32 indexed poolId, IERC20[] tokens, address[] assetManagers);
                /**
                 * @dev Deregisters `tokens` for the `poolId` Pool. Must be called by the Pool's contract.
                 *
                 * Only registered tokens (via `registerTokens`) can be deregistered. Additionally, they must have zero total
                 * balance. For Pools with the Two Token specialization, `tokens` must have a length of two, that is, both tokens
                 * must be deregistered in the same `deregisterTokens` call.
                 *
                 * A deregistered token can be re-registered later on, possibly with a different Asset Manager.
                 *
                 * Emits a `TokensDeregistered` event.
                 */
                function deregisterTokens(bytes32 poolId, IERC20[] memory tokens) external;
                /**
                 * @dev Emitted when a Pool deregisters tokens by calling `deregisterTokens`.
                 */
                event TokensDeregistered(bytes32 indexed poolId, IERC20[] tokens);
                /**
                 * @dev Returns detailed information for a Pool's registered token.
                 *
                 * `cash` is the number of tokens the Vault currently holds for the Pool. `managed` is the number of tokens
                 * withdrawn and held outside the Vault by the Pool's token Asset Manager. The Pool's total balance for `token`
                 * equals the sum of `cash` and `managed`.
                 *
                 * Internally, `cash` and `managed` are stored using 112 bits. No action can ever cause a Pool's token `cash`,
                 * `managed` or `total` balance to be greater than 2^112 - 1.
                 *
                 * `lastChangeBlock` is the number of the block in which `token`'s total balance was last modified (via either a
                 * join, exit, swap, or Asset Manager update). This value is useful to avoid so-called 'sandwich attacks', for
                 * example when developing price oracles. A change of zero (e.g. caused by a swap with amount zero) is considered a
                 * change for this purpose, and will update `lastChangeBlock`.
                 *
                 * `assetManager` is the Pool's token Asset Manager.
                 */
                function getPoolTokenInfo(bytes32 poolId, IERC20 token)
                    external
                    view
                    returns (
                        uint256 cash,
                        uint256 managed,
                        uint256 lastChangeBlock,
                        address assetManager
                    );
                /**
                 * @dev Returns a Pool's registered tokens, the total balance for each, and the latest block when *any* of
                 * the tokens' `balances` changed.
                 *
                 * The order of the `tokens` array is the same order that will be used in `joinPool`, `exitPool`, as well as in all
                 * Pool hooks (where applicable). Calls to `registerTokens` and `deregisterTokens` may change this order.
                 *
                 * If a Pool only registers tokens once, and these are sorted in ascending order, they will be stored in the same
                 * order as passed to `registerTokens`.
                 *
                 * Total balances include both tokens held by the Vault and those withdrawn by the Pool's Asset Managers. These are
                 * the amounts used by joins, exits and swaps. For a detailed breakdown of token balances, use `getPoolTokenInfo`
                 * instead.
                 */
                function getPoolTokens(bytes32 poolId)
                    external
                    view
                    returns (
                        IERC20[] memory tokens,
                        uint256[] memory balances,
                        uint256 lastChangeBlock
                    );
                /**
                 * @dev Called by users to join a Pool, which transfers tokens from `sender` into the Pool's balance. This will
                 * trigger custom Pool behavior, which will typically grant something in return to `recipient` - often tokenized
                 * Pool shares.
                 *
                 * If the caller is not `sender`, it must be an authorized relayer for them.
                 *
                 * The `assets` and `maxAmountsIn` arrays must have the same length, and each entry indicates the maximum amount
                 * to send for each asset. The amounts to send are decided by the Pool and not the Vault: it just enforces
                 * these maximums.
                 *
                 * If joining a Pool that holds WETH, it is possible to send ETH directly: the Vault will do the wrapping. To enable
                 * this mechanism, the IAsset sentinel value (the zero address) must be passed in the `assets` array instead of the
                 * WETH address. Note that it is not possible to combine ETH and WETH in the same join. Any excess ETH will be sent
                 * back to the caller (not the sender, which is important for relayers).
                 *
                 * `assets` must have the same length and order as the array returned by `getPoolTokens`. This prevents issues when
                 * interacting with Pools that register and deregister tokens frequently. If sending ETH however, the array must be
                 * sorted *before* replacing the WETH address with the ETH sentinel value (the zero address), which means the final
                 * `assets` array might not be sorted. Pools with no registered tokens cannot be joined.
                 *
                 * If `fromInternalBalance` is true, the caller's Internal Balance will be preferred: ERC20 transfers will only
                 * be made for the difference between the requested amount and Internal Balance (if any). Note that ETH cannot be
                 * withdrawn from Internal Balance: attempting to do so will trigger a revert.
                 *
                 * This causes the Vault to call the `IBasePool.onJoinPool` hook on the Pool's contract, where Pools implement
                 * their own custom logic. This typically requires additional information from the user (such as the expected number
                 * of Pool shares). This can be encoded in the `userData` argument, which is ignored by the Vault and passed
                 * directly to the Pool's contract, as is `recipient`.
                 *
                 * Emits a `PoolBalanceChanged` event.
                 */
                function joinPool(
                    bytes32 poolId,
                    address sender,
                    address recipient,
                    JoinPoolRequest memory request
                ) external payable;
                struct JoinPoolRequest {
                    IAsset[] assets;
                    uint256[] maxAmountsIn;
                    bytes userData;
                    bool fromInternalBalance;
                }
                /**
                 * @dev Called by users to exit a Pool, which transfers tokens from the Pool's balance to `recipient`. This will
                 * trigger custom Pool behavior, which will typically ask for something in return from `sender` - often tokenized
                 * Pool shares. The amount of tokens that can be withdrawn is limited by the Pool's `cash` balance (see
                 * `getPoolTokenInfo`).
                 *
                 * If the caller is not `sender`, it must be an authorized relayer for them.
                 *
                 * The `tokens` and `minAmountsOut` arrays must have the same length, and each entry in these indicates the minimum
                 * token amount to receive for each token contract. The amounts to send are decided by the Pool and not the Vault:
                 * it just enforces these minimums.
                 *
                 * If exiting a Pool that holds WETH, it is possible to receive ETH directly: the Vault will do the unwrapping. To
                 * enable this mechanism, the IAsset sentinel value (the zero address) must be passed in the `assets` array instead
                 * of the WETH address. Note that it is not possible to combine ETH and WETH in the same exit.
                 *
                 * `assets` must have the same length and order as the array returned by `getPoolTokens`. This prevents issues when
                 * interacting with Pools that register and deregister tokens frequently. If receiving ETH however, the array must
                 * be sorted *before* replacing the WETH address with the ETH sentinel value (the zero address), which means the
                 * final `assets` array might not be sorted. Pools with no registered tokens cannot be exited.
                 *
                 * If `toInternalBalance` is true, the tokens will be deposited to `recipient`'s Internal Balance. Otherwise,
                 * an ERC20 transfer will be performed. Note that ETH cannot be deposited to Internal Balance: attempting to
                 * do so will trigger a revert.
                 *
                 * `minAmountsOut` is the minimum amount of tokens the user expects to get out of the Pool, for each token in the
                 * `tokens` array. This array must match the Pool's registered tokens.
                 *
                 * This causes the Vault to call the `IBasePool.onExitPool` hook on the Pool's contract, where Pools implement
                 * their own custom logic. This typically requires additional information from the user (such as the expected number
                 * of Pool shares to return). This can be encoded in the `userData` argument, which is ignored by the Vault and
                 * passed directly to the Pool's contract.
                 *
                 * Emits a `PoolBalanceChanged` event.
                 */
                function exitPool(
                    bytes32 poolId,
                    address sender,
                    address payable recipient,
                    ExitPoolRequest memory request
                ) external;
                struct ExitPoolRequest {
                    IAsset[] assets;
                    uint256[] minAmountsOut;
                    bytes userData;
                    bool toInternalBalance;
                }
                /**
                 * @dev Emitted when a user joins or exits a Pool by calling `joinPool` or `exitPool`, respectively.
                 */
                event PoolBalanceChanged(
                    bytes32 indexed poolId,
                    address indexed liquidityProvider,
                    IERC20[] tokens,
                    int256[] deltas,
                    uint256[] protocolFeeAmounts
                );
                enum PoolBalanceChangeKind { JOIN, EXIT }
                // Swaps
                //
                // Users can swap tokens with Pools by calling the `swap` and `batchSwap` functions. To do this,
                // they need not trust Pool contracts in any way: all security checks are made by the Vault. They must however be
                // aware of the Pools' pricing algorithms in order to estimate the prices Pools will quote.
                //
                // The `swap` function executes a single swap, while `batchSwap` can perform multiple swaps in sequence.
                // In each individual swap, tokens of one kind are sent from the sender to the Pool (this is the 'token in'),
                // and tokens of another kind are sent from the Pool to the recipient in exchange (this is the 'token out').
                // More complex swaps, such as one token in to multiple tokens out can be achieved by batching together
                // individual swaps.
                //
                // There are two swap kinds:
                //  - 'given in' swaps, where the amount of tokens in (sent to the Pool) is known, and the Pool determines (via the
                // `onSwap` hook) the amount of tokens out (to send to the recipient).
                //  - 'given out' swaps, where the amount of tokens out (received from the Pool) is known, and the Pool determines
                // (via the `onSwap` hook) the amount of tokens in (to receive from the sender).
                //
                // Additionally, it is possible to chain swaps using a placeholder input amount, which the Vault replaces with
                // the calculated output of the previous swap. If the previous swap was 'given in', this will be the calculated
                // tokenOut amount. If the previous swap was 'given out', it will use the calculated tokenIn amount. These extended
                // swaps are known as 'multihop' swaps, since they 'hop' through a number of intermediate tokens before arriving at
                // the final intended token.
                //
                // In all cases, tokens are only transferred in and out of the Vault (or withdrawn from and deposited into Internal
                // Balance) after all individual swaps have been completed, and the net token balance change computed. This makes
                // certain swap patterns, such as multihops, or swaps that interact with the same token pair in multiple Pools, cost
                // much less gas than they would otherwise.
                //
                // It also means that under certain conditions it is possible to perform arbitrage by swapping with multiple
                // Pools in a way that results in net token movement out of the Vault (profit), with no tokens being sent in (only
                // updating the Pool's internal accounting).
                //
                // To protect users from front-running or the market changing rapidly, they supply a list of 'limits' for each token
                // involved in the swap, where either the maximum number of tokens to send (by passing a positive value) or the
                // minimum amount of tokens to receive (by passing a negative value) is specified.
                //
                // Additionally, a 'deadline' timestamp can also be provided, forcing the swap to fail if it occurs after
                // this point in time (e.g. if the transaction failed to be included in a block promptly).
                //
                // If interacting with Pools that hold WETH, it is possible to both send and receive ETH directly: the Vault will do
                // the wrapping and unwrapping. To enable this mechanism, the IAsset sentinel value (the zero address) must be
                // passed in the `assets` array instead of the WETH address. Note that it is possible to combine ETH and WETH in the
                // same swap. Any excess ETH will be sent back to the caller (not the sender, which is relevant for relayers).
                //
                // Finally, Internal Balance can be used when either sending or receiving tokens.
                enum SwapKind { GIVEN_IN, GIVEN_OUT }
                /**
                 * @dev Performs a swap with a single Pool.
                 *
                 * If the swap is 'given in' (the number of tokens to send to the Pool is known), it returns the amount of tokens
                 * taken from the Pool, which must be greater than or equal to `limit`.
                 *
                 * If the swap is 'given out' (the number of tokens to take from the Pool is known), it returns the amount of tokens
                 * sent to the Pool, which must be less than or equal to `limit`.
                 *
                 * Internal Balance usage and the recipient are determined by the `funds` struct.
                 *
                 * Emits a `Swap` event.
                 */
                function swap(
                    SingleSwap memory singleSwap,
                    FundManagement memory funds,
                    uint256 limit,
                    uint256 deadline
                ) external payable returns (uint256);
                /**
                 * @dev Data for a single swap executed by `swap`. `amount` is either `amountIn` or `amountOut` depending on
                 * the `kind` value.
                 *
                 * `assetIn` and `assetOut` are either token addresses, or the IAsset sentinel value for ETH (the zero address).
                 * Note that Pools never interact with ETH directly: it will be wrapped to or unwrapped from WETH by the Vault.
                 *
                 * The `userData` field is ignored by the Vault, but forwarded to the Pool in the `onSwap` hook, and may be
                 * used to extend swap behavior.
                 */
                struct SingleSwap {
                    bytes32 poolId;
                    SwapKind kind;
                    IAsset assetIn;
                    IAsset assetOut;
                    uint256 amount;
                    bytes userData;
                }
                /**
                 * @dev Performs a series of swaps with one or multiple Pools. In each individual swap, the caller determines either
                 * the amount of tokens sent to or received from the Pool, depending on the `kind` value.
                 *
                 * Returns an array with the net Vault asset balance deltas. Positive amounts represent tokens (or ETH) sent to the
                 * Vault, and negative amounts represent tokens (or ETH) sent by the Vault. Each delta corresponds to the asset at
                 * the same index in the `assets` array.
                 *
                 * Swaps are executed sequentially, in the order specified by the `swaps` array. Each array element describes a
                 * Pool, the token to be sent to this Pool, the token to receive from it, and an amount that is either `amountIn` or
                 * `amountOut` depending on the swap kind.
                 *
                 * Multihop swaps can be executed by passing an `amount` value of zero for a swap. This will cause the amount in/out
                 * of the previous swap to be used as the amount in for the current one. In a 'given in' swap, 'tokenIn' must equal
                 * the previous swap's `tokenOut`. For a 'given out' swap, `tokenOut` must equal the previous swap's `tokenIn`.
                 *
                 * The `assets` array contains the addresses of all assets involved in the swaps. These are either token addresses,
                 * or the IAsset sentinel value for ETH (the zero address). Each entry in the `swaps` array specifies tokens in and
                 * out by referencing an index in `assets`. Note that Pools never interact with ETH directly: it will be wrapped to
                 * or unwrapped from WETH by the Vault.
                 *
                 * Internal Balance usage, sender, and recipient are determined by the `funds` struct. The `limits` array specifies
                 * the minimum or maximum amount of each token the vault is allowed to transfer.
                 *
                 * `batchSwap` can be used to make a single swap, like `swap` does, but doing so requires more gas than the
                 * equivalent `swap` call.
                 *
                 * Emits `Swap` events.
                 */
                function batchSwap(
                    SwapKind kind,
                    BatchSwapStep[] memory swaps,
                    IAsset[] memory assets,
                    FundManagement memory funds,
                    int256[] memory limits,
                    uint256 deadline
                ) external payable returns (int256[] memory);
                /**
                 * @dev Data for each individual swap executed by `batchSwap`. The asset in and out fields are indexes into the
                 * `assets` array passed to that function, and ETH assets are converted to WETH.
                 *
                 * If `amount` is zero, the multihop mechanism is used to determine the actual amount based on the amount in/out
                 * from the previous swap, depending on the swap kind.
                 *
                 * The `userData` field is ignored by the Vault, but forwarded to the Pool in the `onSwap` hook, and may be
                 * used to extend swap behavior.
                 */
                struct BatchSwapStep {
                    bytes32 poolId;
                    uint256 assetInIndex;
                    uint256 assetOutIndex;
                    uint256 amount;
                    bytes userData;
                }
                /**
                 * @dev Emitted for each individual swap performed by `swap` or `batchSwap`.
                 */
                event Swap(
                    bytes32 indexed poolId,
                    IERC20 indexed tokenIn,
                    IERC20 indexed tokenOut,
                    uint256 amountIn,
                    uint256 amountOut
                );
                /**
                 * @dev All tokens in a swap are either sent from the `sender` account to the Vault, or from the Vault to the
                 * `recipient` account.
                 *
                 * If the caller is not `sender`, it must be an authorized relayer for them.
                 *
                 * If `fromInternalBalance` is true, the `sender`'s Internal Balance will be preferred, performing an ERC20
                 * transfer for the difference between the requested amount and the User's Internal Balance (if any). The `sender`
                 * must have allowed the Vault to use their tokens via `IERC20.approve()`. This matches the behavior of
                 * `joinPool`.
                 *
                 * If `toInternalBalance` is true, tokens will be deposited to `recipient`'s internal balance instead of
                 * transferred. This matches the behavior of `exitPool`.
                 *
                 * Note that ETH cannot be deposited to or withdrawn from Internal Balance: attempting to do so will trigger a
                 * revert.
                 */
                struct FundManagement {
                    address sender;
                    bool fromInternalBalance;
                    address payable recipient;
                    bool toInternalBalance;
                }
                /**
                 * @dev Simulates a call to `batchSwap`, returning an array of Vault asset deltas. Calls to `swap` cannot be
                 * simulated directly, but an equivalent `batchSwap` call can and will yield the exact same result.
                 *
                 * Each element in the array corresponds to the asset at the same index, and indicates the number of tokens (or ETH)
                 * the Vault would take from the sender (if positive) or send to the recipient (if negative). The arguments it
                 * receives are the same that an equivalent `batchSwap` call would receive.
                 *
                 * Unlike `batchSwap`, this function performs no checks on the sender or recipient field in the `funds` struct.
                 * This makes it suitable to be called by off-chain applications via eth_call without needing to hold tokens,
                 * approve them for the Vault, or even know a user's address.
                 *
                 * Note that this function is not 'view' (due to implementation details): the client code must explicitly execute
                 * eth_call instead of eth_sendTransaction.
                 */
                function queryBatchSwap(
                    SwapKind kind,
                    BatchSwapStep[] memory swaps,
                    IAsset[] memory assets,
                    FundManagement memory funds
                ) external returns (int256[] memory assetDeltas);
                // Flash Loans
                /**
                 * @dev Performs a 'flash loan', sending tokens to `recipient`, executing the `receiveFlashLoan` hook on it,
                 * and then reverting unless the tokens plus a proportional protocol fee have been returned.
                 *
                 * The `tokens` and `amounts` arrays must have the same length, and each entry in these indicates the loan amount
                 * for each token contract. `tokens` must be sorted in ascending order.
                 *
                 * The 'userData' field is ignored by the Vault, and forwarded as-is to `recipient` as part of the
                 * `receiveFlashLoan` call.
                 *
                 * Emits `FlashLoan` events.
                 */
                function flashLoan(
                    IFlashLoanRecipient recipient,
                    IERC20[] memory tokens,
                    uint256[] memory amounts,
                    bytes memory userData
                ) external;
                /**
                 * @dev Emitted for each individual flash loan performed by `flashLoan`.
                 */
                event FlashLoan(IFlashLoanRecipient indexed recipient, IERC20 indexed token, uint256 amount, uint256 feeAmount);
                // Asset Management
                //
                // Each token registered for a Pool can be assigned an Asset Manager, which is able to freely withdraw the Pool's
                // tokens from the Vault, deposit them, or assign arbitrary values to its `managed` balance (see
                // `getPoolTokenInfo`). This makes them extremely powerful and dangerous. Even if an Asset Manager only directly
                // controls one of the tokens in a Pool, a malicious manager could set that token's balance to manipulate the
                // prices of the other tokens, and then drain the Pool with swaps. The risk of using Asset Managers is therefore
                // not constrained to the tokens they are managing, but extends to the entire Pool's holdings.
                //
                // However, a properly designed Asset Manager smart contract can be safely used for the Pool's benefit,
                // for example by lending unused tokens out for interest, or using them to participate in voting protocols.
                //
                // This concept is unrelated to the IAsset interface.
                /**
                 * @dev Performs a set of Pool balance operations, which may be either withdrawals, deposits or updates.
                 *
                 * Pool Balance management features batching, which means a single contract call can be used to perform multiple
                 * operations of different kinds, with different Pools and tokens, at once.
                 *
                 * For each operation, the caller must be registered as the Asset Manager for `token` in `poolId`.
                 */
                function managePoolBalance(PoolBalanceOp[] memory ops) external;
                struct PoolBalanceOp {
                    PoolBalanceOpKind kind;
                    bytes32 poolId;
                    IERC20 token;
                    uint256 amount;
                }
                /**
                 * Withdrawals decrease the Pool's cash, but increase its managed balance, leaving the total balance unchanged.
                 *
                 * Deposits increase the Pool's cash, but decrease its managed balance, leaving the total balance unchanged.
                 *
                 * Updates don't affect the Pool's cash balance, but because the managed balance changes, it does alter the total.
                 * The external amount can be either increased or decreased by this call (i.e., reporting a gain or a loss).
                 */
                enum PoolBalanceOpKind { WITHDRAW, DEPOSIT, UPDATE }
                /**
                 * @dev Emitted when a Pool's token Asset Manager alters its balance via `managePoolBalance`.
                 */
                event PoolBalanceManaged(
                    bytes32 indexed poolId,
                    address indexed assetManager,
                    IERC20 indexed token,
                    int256 cashDelta,
                    int256 managedDelta
                );
                // Protocol Fees
                //
                // Some operations cause the Vault to collect tokens in the form of protocol fees, which can then be withdrawn by
                // permissioned accounts.
                //
                // There are two kinds of protocol fees:
                //
                //  - flash loan fees: charged on all flash loans, as a percentage of the amounts lent.
                //
                //  - swap fees: a percentage of the fees charged by Pools when performing swaps. For a number of reasons, including
                // swap gas costs and interface simplicity, protocol swap fees are not charged on each individual swap. Rather,
                // Pools are expected to keep track of how much they have charged in swap fees, and pay any outstanding debts to the
                // Vault when they are joined or exited. This prevents users from joining a Pool with unpaid debt, as well as
                // exiting a Pool in debt without first paying their share.
                /**
                 * @dev Returns the current protocol fee module.
                 */
                function getProtocolFeesCollector() external view returns (ProtocolFeesCollector);
                /**
                 * @dev Safety mechanism to pause most Vault operations in the event of an emergency - typically detection of an
                 * error in some part of the system.
                 *
                 * The Vault can only be paused during an initial time period, after which pausing is forever disabled.
                 *
                 * While the contract is paused, the following features are disabled:
                 * - depositing and transferring internal balance
                 * - transferring external balance (using the Vault's allowance)
                 * - swaps
                 * - joining Pools
                 * - Asset Manager interactions
                 *
                 * Internal Balance can still be withdrawn, and Pools exited.
                 */
                function setPaused(bool paused) external;
                /**
                 * @dev Returns the Vault's WETH instance.
                 */
                function WETH() external view returns (IWETH);
                // solhint-disable-previous-line func-name-mixedcase
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            interface IAuthentication {
                /**
                 * @dev Returns the action identifier associated with the external function described by `selector`.
                 */
                function getActionId(bytes4 selector) external view returns (bytes32);
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            /**
             * @dev Interface for the TemporarilyPausable helper.
             */
            interface ITemporarilyPausable {
                /**
                 * @dev Emitted every time the pause state changes by `_setPaused`.
                 */
                event PausedStateChanged(bool paused);
                /**
                 * @dev Returns the current paused state.
                 */
                function getPausedState()
                    external
                    view
                    returns (
                        bool paused,
                        uint256 pauseWindowEndTime,
                        uint256 bufferPeriodEndTime
                    );
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            /**
             * @dev Interface for the SignatureValidator helper, used to support meta-transactions.
             */
            interface ISignaturesValidator {
                /**
                 * @dev Returns the EIP712 domain separator.
                 */
                function getDomainSeparator() external view returns (bytes32);
                /**
                 * @dev Returns the next nonce used by an address to sign messages.
                 */
                function getNextNonce(address user) external view returns (uint256);
            }
            // SPDX-License-Identifier: MIT
            pragma solidity ^0.7.0;
            /**
             * @dev https://eips.ethereum.org/EIPS/eip-712[EIP 712] is a standard for hashing and signing of typed structured data.
             *
             * The encoding specified in the EIP is very generic, and such a generic implementation in Solidity is not feasible,
             * thus this contract does not implement the encoding itself. Protocols need to implement the type-specific encoding
             * they need in their contracts using a combination of `abi.encode` and `keccak256`.
             *
             * This contract implements the EIP 712 domain separator ({_domainSeparatorV4}) that is used as part of the encoding
             * scheme, and the final step of the encoding to obtain the message digest that is then signed via ECDSA
             * ({_hashTypedDataV4}).
             *
             * The implementation of the domain separator was designed to be as efficient as possible while still properly updating
             * the chain id to protect against replay attacks on an eventual fork of the chain.
             *
             * NOTE: This contract implements the version of the encoding known as "v4", as implemented by the JSON RPC method
             * https://docs.metamask.io/guide/signing-data.html[`eth_signTypedDataV4` in MetaMask].
             *
             * _Available since v3.4._
             */
            abstract contract EIP712 {
                /* solhint-disable var-name-mixedcase */
                bytes32 private immutable _HASHED_NAME;
                bytes32 private immutable _HASHED_VERSION;
                bytes32 private immutable _TYPE_HASH;
                /* solhint-enable var-name-mixedcase */
                /**
                 * @dev Initializes the domain separator and parameter caches.
                 *
                 * The meaning of `name` and `version` is specified in
                 * https://eips.ethereum.org/EIPS/eip-712#definition-of-domainseparator[EIP 712]:
                 *
                 * - `name`: the user readable name of the signing domain, i.e. the name of the DApp or the protocol.
                 * - `version`: the current major version of the signing domain.
                 *
                 * NOTE: These parameters cannot be changed except through a xref:learn::upgrading-smart-contracts.adoc[smart
                 * contract upgrade].
                 */
                constructor(string memory name, string memory version) {
                    _HASHED_NAME = keccak256(bytes(name));
                    _HASHED_VERSION = keccak256(bytes(version));
                    _TYPE_HASH = keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)");
                }
                /**
                 * @dev Returns the domain separator for the current chain.
                 */
                function _domainSeparatorV4() internal view virtual returns (bytes32) {
                    return keccak256(abi.encode(_TYPE_HASH, _HASHED_NAME, _HASHED_VERSION, _getChainId(), address(this)));
                }
                /**
                 * @dev Given an already https://eips.ethereum.org/EIPS/eip-712#definition-of-hashstruct[hashed struct], this
                 * function returns the hash of the fully encoded EIP712 message for this domain.
                 *
                 * This hash can be used together with {ECDSA-recover} to obtain the signer of a message. For example:
                 *
                 * ```solidity
                 * bytes32 digest = _hashTypedDataV4(keccak256(abi.encode(
                 *     keccak256("Mail(address to,string contents)"),
                 *     mailTo,
                 *     keccak256(bytes(mailContents))
                 * )));
                 * address signer = ECDSA.recover(digest, signature);
                 * ```
                 */
                function _hashTypedDataV4(bytes32 structHash) internal view virtual returns (bytes32) {
                    return keccak256(abi.encodePacked("\\x19\\x01", _domainSeparatorV4(), structHash));
                }
                function _getChainId() private view returns (uint256 chainId) {
                    // Silence state mutability warning without generating bytecode.
                    // See https://github.com/ethereum/solidity/issues/10090#issuecomment-741789128 and
                    // https://github.com/ethereum/solidity/issues/2691
                    this;
                    // solhint-disable-next-line no-inline-assembly
                    assembly {
                        chainId := chainid()
                    }
                }
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            /**
             * @dev This is an empty interface used to represent either ERC20-conforming token contracts or ETH (using the zero
             * address sentinel value). We're just relying on the fact that `interface` can be used to declare new address-like
             * types.
             *
             * This concept is unrelated to a Pool's Asset Managers.
             */
            interface IAsset {
                // solhint-disable-previous-line no-empty-blocks
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            // Inspired by Aave Protocol's IFlashLoanReceiver.
            import "../../lib/openzeppelin/IERC20.sol";
            interface IFlashLoanRecipient {
                /**
                 * @dev When `flashLoan` is called on the Vault, it invokes the `receiveFlashLoan` hook on the recipient.
                 *
                 * At the time of the call, the Vault will have transferred `amounts` for `tokens` to the recipient. Before this
                 * call returns, the recipient must have transferred `amounts` plus `feeAmounts` for each token back to the
                 * Vault, or else the entire flash loan will revert.
                 *
                 * `userData` is the same value passed in the `IVault.flashLoan` call.
                 */
                function receiveFlashLoan(
                    IERC20[] memory tokens,
                    uint256[] memory amounts,
                    uint256[] memory feeAmounts,
                    bytes memory userData
                ) external;
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            pragma experimental ABIEncoderV2;
            import "../lib/openzeppelin/IERC20.sol";
            import "../lib/helpers/InputHelpers.sol";
            import "../lib/helpers/Authentication.sol";
            import "../lib/openzeppelin/ReentrancyGuard.sol";
            import "../lib/openzeppelin/SafeERC20.sol";
            import "./interfaces/IVault.sol";
            import "./interfaces/IAuthorizer.sol";
            /**
             * @dev This an auxiliary contract to the Vault, deployed by it during construction. It offloads some of the tasks the
             * Vault performs to reduce its overall bytecode size.
             *
             * The current values for all protocol fee percentages are stored here, and any tokens charged as protocol fees are
             * sent to this contract, where they may be withdrawn by authorized entities. All authorization tasks are delegated
             * to the Vault's own authorizer.
             */
            contract ProtocolFeesCollector is Authentication, ReentrancyGuard {
                using SafeERC20 for IERC20;
                // Absolute maximum fee percentages (1e18 = 100%, 1e16 = 1%).
                uint256 private constant _MAX_PROTOCOL_SWAP_FEE_PERCENTAGE = 50e16; // 50%
                uint256 private constant _MAX_PROTOCOL_FLASH_LOAN_FEE_PERCENTAGE = 1e16; // 1%
                IVault public immutable vault;
                // All fee percentages are 18-decimal fixed point numbers.
                // The swap fee is charged whenever a swap occurs, as a percentage of the fee charged by the Pool. These are not
                // actually charged on each individual swap: the `Vault` relies on the Pools being honest and reporting fees due
                // when users join and exit them.
                uint256 private _swapFeePercentage;
                // The flash loan fee is charged whenever a flash loan occurs, as a percentage of the tokens lent.
                uint256 private _flashLoanFeePercentage;
                event SwapFeePercentageChanged(uint256 newSwapFeePercentage);
                event FlashLoanFeePercentageChanged(uint256 newFlashLoanFeePercentage);
                constructor(IVault _vault)
                    // The ProtocolFeesCollector is a singleton, so it simply uses its own address to disambiguate action
                    // identifiers.
                    Authentication(bytes32(uint256(address(this))))
                {
                    vault = _vault;
                }
                function withdrawCollectedFees(
                    IERC20[] calldata tokens,
                    uint256[] calldata amounts,
                    address recipient
                ) external nonReentrant authenticate {
                    InputHelpers.ensureInputLengthMatch(tokens.length, amounts.length);
                    for (uint256 i = 0; i < tokens.length; ++i) {
                        IERC20 token = tokens[i];
                        uint256 amount = amounts[i];
                        token.safeTransfer(recipient, amount);
                    }
                }
                function setSwapFeePercentage(uint256 newSwapFeePercentage) external authenticate {
                    _require(newSwapFeePercentage <= _MAX_PROTOCOL_SWAP_FEE_PERCENTAGE, Errors.SWAP_FEE_PERCENTAGE_TOO_HIGH);
                    _swapFeePercentage = newSwapFeePercentage;
                    emit SwapFeePercentageChanged(newSwapFeePercentage);
                }
                function setFlashLoanFeePercentage(uint256 newFlashLoanFeePercentage) external authenticate {
                    _require(
                        newFlashLoanFeePercentage <= _MAX_PROTOCOL_FLASH_LOAN_FEE_PERCENTAGE,
                        Errors.FLASH_LOAN_FEE_PERCENTAGE_TOO_HIGH
                    );
                    _flashLoanFeePercentage = newFlashLoanFeePercentage;
                    emit FlashLoanFeePercentageChanged(newFlashLoanFeePercentage);
                }
                function getSwapFeePercentage() external view returns (uint256) {
                    return _swapFeePercentage;
                }
                function getFlashLoanFeePercentage() external view returns (uint256) {
                    return _flashLoanFeePercentage;
                }
                function getCollectedFeeAmounts(IERC20[] memory tokens) external view returns (uint256[] memory feeAmounts) {
                    feeAmounts = new uint256[](tokens.length);
                    for (uint256 i = 0; i < tokens.length; ++i) {
                        feeAmounts[i] = tokens[i].balanceOf(address(this));
                    }
                }
                function getAuthorizer() external view returns (IAuthorizer) {
                    return _getAuthorizer();
                }
                function _canPerform(bytes32 actionId, address account) internal view override returns (bool) {
                    return _getAuthorizer().canPerform(actionId, account, address(this));
                }
                function _getAuthorizer() internal view returns (IAuthorizer) {
                    return vault.getAuthorizer();
                }
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            import "../openzeppelin/IERC20.sol";
            import "./BalancerErrors.sol";
            import "../../vault/interfaces/IAsset.sol";
            library InputHelpers {
                function ensureInputLengthMatch(uint256 a, uint256 b) internal pure {
                    _require(a == b, Errors.INPUT_LENGTH_MISMATCH);
                }
                function ensureInputLengthMatch(
                    uint256 a,
                    uint256 b,
                    uint256 c
                ) internal pure {
                    _require(a == b && b == c, Errors.INPUT_LENGTH_MISMATCH);
                }
                function ensureArrayIsSorted(IAsset[] memory array) internal pure {
                    address[] memory addressArray;
                    // solhint-disable-next-line no-inline-assembly
                    assembly {
                        addressArray := array
                    }
                    ensureArrayIsSorted(addressArray);
                }
                function ensureArrayIsSorted(IERC20[] memory array) internal pure {
                    address[] memory addressArray;
                    // solhint-disable-next-line no-inline-assembly
                    assembly {
                        addressArray := array
                    }
                    ensureArrayIsSorted(addressArray);
                }
                function ensureArrayIsSorted(address[] memory array) internal pure {
                    if (array.length < 2) {
                        return;
                    }
                    address previous = array[0];
                    for (uint256 i = 1; i < array.length; ++i) {
                        address current = array[i];
                        _require(previous < current, Errors.UNSORTED_ARRAY);
                        previous = current;
                    }
                }
            }
            // SPDX-License-Identifier: MIT
            pragma solidity ^0.7.0;
            import "../helpers/BalancerErrors.sol";
            import "./IERC20.sol";
            /**
             * @title SafeERC20
             * @dev Wrappers around ERC20 operations that throw on failure (when the token
             * contract returns false). Tokens that return no value (and instead revert or
             * throw on failure) are also supported, non-reverting calls are assumed to be
             * successful.
             * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
             * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
             */
            library SafeERC20 {
                function safeTransfer(
                    IERC20 token,
                    address to,
                    uint256 value
                ) internal {
                    _callOptionalReturn(address(token), abi.encodeWithSelector(token.transfer.selector, to, value));
                }
                function safeTransferFrom(
                    IERC20 token,
                    address from,
                    address to,
                    uint256 value
                ) internal {
                    _callOptionalReturn(address(token), abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
                }
                /**
                 * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
                 * on the return value: the return value is optional (but if data is returned, it must not be false).
                 *
                 * WARNING: `token` is assumed to be a contract: calls to EOAs will *not* revert.
                 */
                function _callOptionalReturn(address token, bytes memory data) private {
                    // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
                    // we're implementing it ourselves.
                    (bool success, bytes memory returndata) = token.call(data);
                    // If the low-level call didn't succeed we return whatever was returned from it.
                    assembly {
                        if eq(success, 0) {
                            returndatacopy(0, 0, returndatasize())
                            revert(0, returndatasize())
                        }
                    }
                    // Finally we check the returndata size is either zero or true - note that this check will always pass for EOAs
                    _require(returndata.length == 0 || abi.decode(returndata, (bool)), Errors.SAFE_ERC20_CALL_FAILED);
                }
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            pragma experimental ABIEncoderV2;
            import "../lib/math/FixedPoint.sol";
            import "../lib/helpers/BalancerErrors.sol";
            import "../lib/openzeppelin/IERC20.sol";
            import "../lib/openzeppelin/ReentrancyGuard.sol";
            import "../lib/openzeppelin/SafeERC20.sol";
            import "./ProtocolFeesCollector.sol";
            import "./VaultAuthorization.sol";
            import "./interfaces/IVault.sol";
            /**
             * @dev To reduce the bytecode size of the Vault, most of the protocol fee logic is not here, but in the
             * ProtocolFeesCollector contract.
             */
            abstract contract Fees is IVault {
                using SafeERC20 for IERC20;
                ProtocolFeesCollector private immutable _protocolFeesCollector;
                constructor() {
                    _protocolFeesCollector = new ProtocolFeesCollector(IVault(this));
                }
                function getProtocolFeesCollector() public view override returns (ProtocolFeesCollector) {
                    return _protocolFeesCollector;
                }
                /**
                 * @dev Returns the protocol swap fee percentage.
                 */
                function _getProtocolSwapFeePercentage() internal view returns (uint256) {
                    return getProtocolFeesCollector().getSwapFeePercentage();
                }
                /**
                 * @dev Returns the protocol fee amount to charge for a flash loan of `amount`.
                 */
                function _calculateFlashLoanFeeAmount(uint256 amount) internal view returns (uint256) {
                    // Fixed point multiplication introduces error: we round up, which means in certain scenarios the charged
                    // percentage can be slightly higher than intended.
                    uint256 percentage = getProtocolFeesCollector().getFlashLoanFeePercentage();
                    return FixedPoint.mulUp(amount, percentage);
                }
                function _payFeeAmount(IERC20 token, uint256 amount) internal {
                    if (amount > 0) {
                        token.safeTransfer(address(getProtocolFeesCollector()), amount);
                    }
                }
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            import "./LogExpMath.sol";
            import "../helpers/BalancerErrors.sol";
            /* solhint-disable private-vars-leading-underscore */
            library FixedPoint {
                uint256 internal constant ONE = 1e18; // 18 decimal places
                uint256 internal constant MAX_POW_RELATIVE_ERROR = 10000; // 10^(-14)
                // Minimum base for the power function when the exponent is 'free' (larger than ONE).
                uint256 internal constant MIN_POW_BASE_FREE_EXPONENT = 0.7e18;
                function add(uint256 a, uint256 b) internal pure returns (uint256) {
                    // Fixed Point addition is the same as regular checked addition
                    uint256 c = a + b;
                    _require(c >= a, Errors.ADD_OVERFLOW);
                    return c;
                }
                function sub(uint256 a, uint256 b) internal pure returns (uint256) {
                    // Fixed Point addition is the same as regular checked addition
                    _require(b <= a, Errors.SUB_OVERFLOW);
                    uint256 c = a - b;
                    return c;
                }
                function mulDown(uint256 a, uint256 b) internal pure returns (uint256) {
                    uint256 product = a * b;
                    _require(a == 0 || product / a == b, Errors.MUL_OVERFLOW);
                    return product / ONE;
                }
                function mulUp(uint256 a, uint256 b) internal pure returns (uint256) {
                    uint256 product = a * b;
                    _require(a == 0 || product / a == b, Errors.MUL_OVERFLOW);
                    if (product == 0) {
                        return 0;
                    } else {
                        // The traditional divUp formula is:
                        // divUp(x, y) := (x + y - 1) / y
                        // To avoid intermediate overflow in the addition, we distribute the division and get:
                        // divUp(x, y) := (x - 1) / y + 1
                        // Note that this requires x != 0, which we already tested for.
                        return ((product - 1) / ONE) + 1;
                    }
                }
                function divDown(uint256 a, uint256 b) internal pure returns (uint256) {
                    _require(b != 0, Errors.ZERO_DIVISION);
                    if (a == 0) {
                        return 0;
                    } else {
                        uint256 aInflated = a * ONE;
                        _require(aInflated / a == ONE, Errors.DIV_INTERNAL); // mul overflow
                        return aInflated / b;
                    }
                }
                function divUp(uint256 a, uint256 b) internal pure returns (uint256) {
                    _require(b != 0, Errors.ZERO_DIVISION);
                    if (a == 0) {
                        return 0;
                    } else {
                        uint256 aInflated = a * ONE;
                        _require(aInflated / a == ONE, Errors.DIV_INTERNAL); // mul overflow
                        // The traditional divUp formula is:
                        // divUp(x, y) := (x + y - 1) / y
                        // To avoid intermediate overflow in the addition, we distribute the division and get:
                        // divUp(x, y) := (x - 1) / y + 1
                        // Note that this requires x != 0, which we already tested for.
                        return ((aInflated - 1) / b) + 1;
                    }
                }
                /**
                 * @dev Returns x^y, assuming both are fixed point numbers, rounding down. The result is guaranteed to not be above
                 * the true value (that is, the error function expected - actual is always positive).
                 */
                function powDown(uint256 x, uint256 y) internal pure returns (uint256) {
                    uint256 raw = LogExpMath.pow(x, y);
                    uint256 maxError = add(mulUp(raw, MAX_POW_RELATIVE_ERROR), 1);
                    if (raw < maxError) {
                        return 0;
                    } else {
                        return sub(raw, maxError);
                    }
                }
                /**
                 * @dev Returns x^y, assuming both are fixed point numbers, rounding up. The result is guaranteed to not be below
                 * the true value (that is, the error function expected - actual is always negative).
                 */
                function powUp(uint256 x, uint256 y) internal pure returns (uint256) {
                    uint256 raw = LogExpMath.pow(x, y);
                    uint256 maxError = add(mulUp(raw, MAX_POW_RELATIVE_ERROR), 1);
                    return add(raw, maxError);
                }
                /**
                 * @dev Returns the complement of a value (1 - x), capped to 0 if x is larger than 1.
                 *
                 * Useful when computing the complement for values with some level of relative error, as it strips this error and
                 * prevents intermediate negative values.
                 */
                function complement(uint256 x) internal pure returns (uint256) {
                    return (x < ONE) ? (ONE - x) : 0;
                }
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General internal License for more details.
            // You should have received a copy of the GNU General internal License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            import "../helpers/BalancerErrors.sol";
            /* solhint-disable */
            /**
             * @dev Exponentiation and logarithm functions for 18 decimal fixed point numbers (both base and exponent/argument).
             *
             * Exponentiation and logarithm with arbitrary bases (x^y and log_x(y)) are implemented by conversion to natural
             * exponentiation and logarithm (where the base is Euler's number).
             *
             * @author Fernando Martinelli - @fernandomartinelli
             * @author Sergio Yuhjtman - @sergioyuhjtman
             * @author Daniel Fernandez - @dmf7z
             */
            library LogExpMath {
                // All fixed point multiplications and divisions are inlined. This means we need to divide by ONE when multiplying
                // two numbers, and multiply by ONE when dividing them.
                // All arguments and return values are 18 decimal fixed point numbers.
                int256 constant ONE_18 = 1e18;
                // Internally, intermediate values are computed with higher precision as 20 decimal fixed point numbers, and in the
                // case of ln36, 36 decimals.
                int256 constant ONE_20 = 1e20;
                int256 constant ONE_36 = 1e36;
                // The domain of natural exponentiation is bound by the word size and number of decimals used.
                //
                // Because internally the result will be stored using 20 decimals, the largest possible result is
                // (2^255 - 1) / 10^20, which makes the largest exponent ln((2^255 - 1) / 10^20) = 130.700829182905140221.
                // The smallest possible result is 10^(-18), which makes largest negative argument
                // ln(10^(-18)) = -41.446531673892822312.
                // We use 130.0 and -41.0 to have some safety margin.
                int256 constant MAX_NATURAL_EXPONENT = 130e18;
                int256 constant MIN_NATURAL_EXPONENT = -41e18;
                // Bounds for ln_36's argument. Both ln(0.9) and ln(1.1) can be represented with 36 decimal places in a fixed point
                // 256 bit integer.
                int256 constant LN_36_LOWER_BOUND = ONE_18 - 1e17;
                int256 constant LN_36_UPPER_BOUND = ONE_18 + 1e17;
                uint256 constant MILD_EXPONENT_BOUND = 2**254 / uint256(ONE_20);
                // 18 decimal constants
                int256 constant x0 = 128000000000000000000; // 2ˆ7
                int256 constant a0 = 38877084059945950922200000000000000000000000000000000000; // eˆ(x0) (no decimals)
                int256 constant x1 = 64000000000000000000; // 2ˆ6
                int256 constant a1 = 6235149080811616882910000000; // eˆ(x1) (no decimals)
                // 20 decimal constants
                int256 constant x2 = 3200000000000000000000; // 2ˆ5
                int256 constant a2 = 7896296018268069516100000000000000; // eˆ(x2)
                int256 constant x3 = 1600000000000000000000; // 2ˆ4
                int256 constant a3 = 888611052050787263676000000; // eˆ(x3)
                int256 constant x4 = 800000000000000000000; // 2ˆ3
                int256 constant a4 = 298095798704172827474000; // eˆ(x4)
                int256 constant x5 = 400000000000000000000; // 2ˆ2
                int256 constant a5 = 5459815003314423907810; // eˆ(x5)
                int256 constant x6 = 200000000000000000000; // 2ˆ1
                int256 constant a6 = 738905609893065022723; // eˆ(x6)
                int256 constant x7 = 100000000000000000000; // 2ˆ0
                int256 constant a7 = 271828182845904523536; // eˆ(x7)
                int256 constant x8 = 50000000000000000000; // 2ˆ-1
                int256 constant a8 = 164872127070012814685; // eˆ(x8)
                int256 constant x9 = 25000000000000000000; // 2ˆ-2
                int256 constant a9 = 128402541668774148407; // eˆ(x9)
                int256 constant x10 = 12500000000000000000; // 2ˆ-3
                int256 constant a10 = 113314845306682631683; // eˆ(x10)
                int256 constant x11 = 6250000000000000000; // 2ˆ-4
                int256 constant a11 = 106449445891785942956; // eˆ(x11)
                /**
                 * @dev Exponentiation (x^y) with unsigned 18 decimal fixed point base and exponent.
                 *
                 * Reverts if ln(x) * y is smaller than `MIN_NATURAL_EXPONENT`, or larger than `MAX_NATURAL_EXPONENT`.
                 */
                function pow(uint256 x, uint256 y) internal pure returns (uint256) {
                    if (y == 0) {
                        // We solve the 0^0 indetermination by making it equal one.
                        return uint256(ONE_18);
                    }
                    if (x == 0) {
                        return 0;
                    }
                    // Instead of computing x^y directly, we instead rely on the properties of logarithms and exponentiation to
                    // arrive at that result. In particular, exp(ln(x)) = x, and ln(x^y) = y * ln(x). This means
                    // x^y = exp(y * ln(x)).
                    // The ln function takes a signed value, so we need to make sure x fits in the signed 256 bit range.
                    _require(x < 2**255, Errors.X_OUT_OF_BOUNDS);
                    int256 x_int256 = int256(x);
                    // We will compute y * ln(x) in a single step. Depending on the value of x, we can either use ln or ln_36. In
                    // both cases, we leave the division by ONE_18 (due to fixed point multiplication) to the end.
                    // This prevents y * ln(x) from overflowing, and at the same time guarantees y fits in the signed 256 bit range.
                    _require(y < MILD_EXPONENT_BOUND, Errors.Y_OUT_OF_BOUNDS);
                    int256 y_int256 = int256(y);
                    int256 logx_times_y;
                    if (LN_36_LOWER_BOUND < x_int256 && x_int256 < LN_36_UPPER_BOUND) {
                        int256 ln_36_x = ln_36(x_int256);
                        // ln_36_x has 36 decimal places, so multiplying by y_int256 isn't as straightforward, since we can't just
                        // bring y_int256 to 36 decimal places, as it might overflow. Instead, we perform two 18 decimal
                        // multiplications and add the results: one with the first 18 decimals of ln_36_x, and one with the
                        // (downscaled) last 18 decimals.
                        logx_times_y = ((ln_36_x / ONE_18) * y_int256 + ((ln_36_x % ONE_18) * y_int256) / ONE_18);
                    } else {
                        logx_times_y = ln(x_int256) * y_int256;
                    }
                    logx_times_y /= ONE_18;
                    // Finally, we compute exp(y * ln(x)) to arrive at x^y
                    _require(
                        MIN_NATURAL_EXPONENT <= logx_times_y && logx_times_y <= MAX_NATURAL_EXPONENT,
                        Errors.PRODUCT_OUT_OF_BOUNDS
                    );
                    return uint256(exp(logx_times_y));
                }
                /**
                 * @dev Natural exponentiation (e^x) with signed 18 decimal fixed point exponent.
                 *
                 * Reverts if `x` is smaller than MIN_NATURAL_EXPONENT, or larger than `MAX_NATURAL_EXPONENT`.
                 */
                function exp(int256 x) internal pure returns (int256) {
                    _require(x >= MIN_NATURAL_EXPONENT && x <= MAX_NATURAL_EXPONENT, Errors.INVALID_EXPONENT);
                    if (x < 0) {
                        // We only handle positive exponents: e^(-x) is computed as 1 / e^x. We can safely make x positive since it
                        // fits in the signed 256 bit range (as it is larger than MIN_NATURAL_EXPONENT).
                        // Fixed point division requires multiplying by ONE_18.
                        return ((ONE_18 * ONE_18) / exp(-x));
                    }
                    // First, we use the fact that e^(x+y) = e^x * e^y to decompose x into a sum of powers of two, which we call x_n,
                    // where x_n == 2^(7 - n), and e^x_n = a_n has been precomputed. We choose the first x_n, x0, to equal 2^7
                    // because all larger powers are larger than MAX_NATURAL_EXPONENT, and therefore not present in the
                    // decomposition.
                    // At the end of this process we will have the product of all e^x_n = a_n that apply, and the remainder of this
                    // decomposition, which will be lower than the smallest x_n.
                    // exp(x) = k_0 * a_0 * k_1 * a_1 * ... + k_n * a_n * exp(remainder), where each k_n equals either 0 or 1.
                    // We mutate x by subtracting x_n, making it the remainder of the decomposition.
                    // The first two a_n (e^(2^7) and e^(2^6)) are too large if stored as 18 decimal numbers, and could cause
                    // intermediate overflows. Instead we store them as plain integers, with 0 decimals.
                    // Additionally, x0 + x1 is larger than MAX_NATURAL_EXPONENT, which means they will not both be present in the
                    // decomposition.
                    // For each x_n, we test if that term is present in the decomposition (if x is larger than it), and if so deduct
                    // it and compute the accumulated product.
                    int256 firstAN;
                    if (x >= x0) {
                        x -= x0;
                        firstAN = a0;
                    } else if (x >= x1) {
                        x -= x1;
                        firstAN = a1;
                    } else {
                        firstAN = 1; // One with no decimal places
                    }
                    // We now transform x into a 20 decimal fixed point number, to have enhanced precision when computing the
                    // smaller terms.
                    x *= 100;
                    // `product` is the accumulated product of all a_n (except a0 and a1), which starts at 20 decimal fixed point
                    // one. Recall that fixed point multiplication requires dividing by ONE_20.
                    int256 product = ONE_20;
                    if (x >= x2) {
                        x -= x2;
                        product = (product * a2) / ONE_20;
                    }
                    if (x >= x3) {
                        x -= x3;
                        product = (product * a3) / ONE_20;
                    }
                    if (x >= x4) {
                        x -= x4;
                        product = (product * a4) / ONE_20;
                    }
                    if (x >= x5) {
                        x -= x5;
                        product = (product * a5) / ONE_20;
                    }
                    if (x >= x6) {
                        x -= x6;
                        product = (product * a6) / ONE_20;
                    }
                    if (x >= x7) {
                        x -= x7;
                        product = (product * a7) / ONE_20;
                    }
                    if (x >= x8) {
                        x -= x8;
                        product = (product * a8) / ONE_20;
                    }
                    if (x >= x9) {
                        x -= x9;
                        product = (product * a9) / ONE_20;
                    }
                    // x10 and x11 are unnecessary here since we have high enough precision already.
                    // Now we need to compute e^x, where x is small (in particular, it is smaller than x9). We use the Taylor series
                    // expansion for e^x: 1 + x + (x^2 / 2!) + (x^3 / 3!) + ... + (x^n / n!).
                    int256 seriesSum = ONE_20; // The initial one in the sum, with 20 decimal places.
                    int256 term; // Each term in the sum, where the nth term is (x^n / n!).
                    // The first term is simply x.
                    term = x;
                    seriesSum += term;
                    // Each term (x^n / n!) equals the previous one times x, divided by n. Since x is a fixed point number,
                    // multiplying by it requires dividing by ONE_20, but dividing by the non-fixed point n values does not.
                    term = ((term * x) / ONE_20) / 2;
                    seriesSum += term;
                    term = ((term * x) / ONE_20) / 3;
                    seriesSum += term;
                    term = ((term * x) / ONE_20) / 4;
                    seriesSum += term;
                    term = ((term * x) / ONE_20) / 5;
                    seriesSum += term;
                    term = ((term * x) / ONE_20) / 6;
                    seriesSum += term;
                    term = ((term * x) / ONE_20) / 7;
                    seriesSum += term;
                    term = ((term * x) / ONE_20) / 8;
                    seriesSum += term;
                    term = ((term * x) / ONE_20) / 9;
                    seriesSum += term;
                    term = ((term * x) / ONE_20) / 10;
                    seriesSum += term;
                    term = ((term * x) / ONE_20) / 11;
                    seriesSum += term;
                    term = ((term * x) / ONE_20) / 12;
                    seriesSum += term;
                    // 12 Taylor terms are sufficient for 18 decimal precision.
                    // We now have the first a_n (with no decimals), and the product of all other a_n present, and the Taylor
                    // approximation of the exponentiation of the remainder (both with 20 decimals). All that remains is to multiply
                    // all three (one 20 decimal fixed point multiplication, dividing by ONE_20, and one integer multiplication),
                    // and then drop two digits to return an 18 decimal value.
                    return (((product * seriesSum) / ONE_20) * firstAN) / 100;
                }
                /**
                 * @dev Natural logarithm (ln(a)) with signed 18 decimal fixed point argument.
                 */
                function ln(int256 a) internal pure returns (int256) {
                    // The real natural logarithm is not defined for negative numbers or zero.
                    _require(a > 0, Errors.OUT_OF_BOUNDS);
                    if (a < ONE_18) {
                        // Since ln(a^k) = k * ln(a), we can compute ln(a) as ln(a) = ln((1/a)^(-1)) = - ln((1/a)). If a is less
                        // than one, 1/a will be greater than one, and this if statement will not be entered in the recursive call.
                        // Fixed point division requires multiplying by ONE_18.
                        return (-ln((ONE_18 * ONE_18) / a));
                    }
                    // First, we use the fact that ln^(a * b) = ln(a) + ln(b) to decompose ln(a) into a sum of powers of two, which
                    // we call x_n, where x_n == 2^(7 - n), which are the natural logarithm of precomputed quantities a_n (that is,
                    // ln(a_n) = x_n). We choose the first x_n, x0, to equal 2^7 because the exponential of all larger powers cannot
                    // be represented as 18 fixed point decimal numbers in 256 bits, and are therefore larger than a.
                    // At the end of this process we will have the sum of all x_n = ln(a_n) that apply, and the remainder of this
                    // decomposition, which will be lower than the smallest a_n.
                    // ln(a) = k_0 * x_0 + k_1 * x_1 + ... + k_n * x_n + ln(remainder), where each k_n equals either 0 or 1.
                    // We mutate a by subtracting a_n, making it the remainder of the decomposition.
                    // For reasons related to how `exp` works, the first two a_n (e^(2^7) and e^(2^6)) are not stored as fixed point
                    // numbers with 18 decimals, but instead as plain integers with 0 decimals, so we need to multiply them by
                    // ONE_18 to convert them to fixed point.
                    // For each a_n, we test if that term is present in the decomposition (if a is larger than it), and if so divide
                    // by it and compute the accumulated sum.
                    int256 sum = 0;
                    if (a >= a0 * ONE_18) {
                        a /= a0; // Integer, not fixed point division
                        sum += x0;
                    }
                    if (a >= a1 * ONE_18) {
                        a /= a1; // Integer, not fixed point division
                        sum += x1;
                    }
                    // All other a_n and x_n are stored as 20 digit fixed point numbers, so we convert the sum and a to this format.
                    sum *= 100;
                    a *= 100;
                    // Because further a_n are  20 digit fixed point numbers, we multiply by ONE_20 when dividing by them.
                    if (a >= a2) {
                        a = (a * ONE_20) / a2;
                        sum += x2;
                    }
                    if (a >= a3) {
                        a = (a * ONE_20) / a3;
                        sum += x3;
                    }
                    if (a >= a4) {
                        a = (a * ONE_20) / a4;
                        sum += x4;
                    }
                    if (a >= a5) {
                        a = (a * ONE_20) / a5;
                        sum += x5;
                    }
                    if (a >= a6) {
                        a = (a * ONE_20) / a6;
                        sum += x6;
                    }
                    if (a >= a7) {
                        a = (a * ONE_20) / a7;
                        sum += x7;
                    }
                    if (a >= a8) {
                        a = (a * ONE_20) / a8;
                        sum += x8;
                    }
                    if (a >= a9) {
                        a = (a * ONE_20) / a9;
                        sum += x9;
                    }
                    if (a >= a10) {
                        a = (a * ONE_20) / a10;
                        sum += x10;
                    }
                    if (a >= a11) {
                        a = (a * ONE_20) / a11;
                        sum += x11;
                    }
                    // a is now a small number (smaller than a_11, which roughly equals 1.06). This means we can use a Taylor series
                    // that converges rapidly for values of `a` close to one - the same one used in ln_36.
                    // Let z = (a - 1) / (a + 1).
                    // ln(a) = 2 * (z + z^3 / 3 + z^5 / 5 + z^7 / 7 + ... + z^(2 * n + 1) / (2 * n + 1))
                    // Recall that 20 digit fixed point division requires multiplying by ONE_20, and multiplication requires
                    // division by ONE_20.
                    int256 z = ((a - ONE_20) * ONE_20) / (a + ONE_20);
                    int256 z_squared = (z * z) / ONE_20;
                    // num is the numerator of the series: the z^(2 * n + 1) term
                    int256 num = z;
                    // seriesSum holds the accumulated sum of each term in the series, starting with the initial z
                    int256 seriesSum = num;
                    // In each step, the numerator is multiplied by z^2
                    num = (num * z_squared) / ONE_20;
                    seriesSum += num / 3;
                    num = (num * z_squared) / ONE_20;
                    seriesSum += num / 5;
                    num = (num * z_squared) / ONE_20;
                    seriesSum += num / 7;
                    num = (num * z_squared) / ONE_20;
                    seriesSum += num / 9;
                    num = (num * z_squared) / ONE_20;
                    seriesSum += num / 11;
                    // 6 Taylor terms are sufficient for 36 decimal precision.
                    // Finally, we multiply by 2 (non fixed point) to compute ln(remainder)
                    seriesSum *= 2;
                    // We now have the sum of all x_n present, and the Taylor approximation of the logarithm of the remainder (both
                    // with 20 decimals). All that remains is to sum these two, and then drop two digits to return a 18 decimal
                    // value.
                    return (sum + seriesSum) / 100;
                }
                /**
                 * @dev Logarithm (log(arg, base), with signed 18 decimal fixed point base and argument argument.
                 */
                function log(int256 arg, int256 base) internal pure returns (int256) {
                    // This performs a simple base change: log(arg, base) = ln(arg) / ln(base).
                    // Both logBase and logArg are computed as 36 decimal fixed point numbers, either by using ln_36, or by
                    // upscaling.
                    int256 logBase;
                    if (LN_36_LOWER_BOUND < base && base < LN_36_UPPER_BOUND) {
                        logBase = ln_36(base);
                    } else {
                        logBase = ln(base) * ONE_18;
                    }
                    int256 logArg;
                    if (LN_36_LOWER_BOUND < arg && arg < LN_36_UPPER_BOUND) {
                        logArg = ln_36(arg);
                    } else {
                        logArg = ln(arg) * ONE_18;
                    }
                    // When dividing, we multiply by ONE_18 to arrive at a result with 18 decimal places
                    return (logArg * ONE_18) / logBase;
                }
                /**
                 * @dev High precision (36 decimal places) natural logarithm (ln(x)) with signed 18 decimal fixed point argument,
                 * for x close to one.
                 *
                 * Should only be used if x is between LN_36_LOWER_BOUND and LN_36_UPPER_BOUND.
                 */
                function ln_36(int256 x) private pure returns (int256) {
                    // Since ln(1) = 0, a value of x close to one will yield a very small result, which makes using 36 digits
                    // worthwhile.
                    // First, we transform x to a 36 digit fixed point value.
                    x *= ONE_18;
                    // We will use the following Taylor expansion, which converges very rapidly. Let z = (x - 1) / (x + 1).
                    // ln(x) = 2 * (z + z^3 / 3 + z^5 / 5 + z^7 / 7 + ... + z^(2 * n + 1) / (2 * n + 1))
                    // Recall that 36 digit fixed point division requires multiplying by ONE_36, and multiplication requires
                    // division by ONE_36.
                    int256 z = ((x - ONE_36) * ONE_36) / (x + ONE_36);
                    int256 z_squared = (z * z) / ONE_36;
                    // num is the numerator of the series: the z^(2 * n + 1) term
                    int256 num = z;
                    // seriesSum holds the accumulated sum of each term in the series, starting with the initial z
                    int256 seriesSum = num;
                    // In each step, the numerator is multiplied by z^2
                    num = (num * z_squared) / ONE_36;
                    seriesSum += num / 3;
                    num = (num * z_squared) / ONE_36;
                    seriesSum += num / 5;
                    num = (num * z_squared) / ONE_36;
                    seriesSum += num / 7;
                    num = (num * z_squared) / ONE_36;
                    seriesSum += num / 9;
                    num = (num * z_squared) / ONE_36;
                    seriesSum += num / 11;
                    num = (num * z_squared) / ONE_36;
                    seriesSum += num / 13;
                    num = (num * z_squared) / ONE_36;
                    seriesSum += num / 15;
                    // 8 Taylor terms are sufficient for 36 decimal precision.
                    // All that remains is multiplying by 2 (non fixed point).
                    return seriesSum * 2;
                }
            }
            // SPDX-License-Identifier: MIT
            pragma solidity ^0.7.0;
            import "../helpers/BalancerErrors.sol";
            /**
             * @dev Wrappers over Solidity's arithmetic operations with added overflow checks.
             * Adapted from OpenZeppelin's SafeMath library
             */
            library Math {
                /**
                 * @dev Returns the addition of two unsigned integers of 256 bits, reverting on overflow.
                 */
                function add(uint256 a, uint256 b) internal pure returns (uint256) {
                    uint256 c = a + b;
                    _require(c >= a, Errors.ADD_OVERFLOW);
                    return c;
                }
                /**
                 * @dev Returns the addition of two signed integers, reverting on overflow.
                 */
                function add(int256 a, int256 b) internal pure returns (int256) {
                    int256 c = a + b;
                    _require((b >= 0 && c >= a) || (b < 0 && c < a), Errors.ADD_OVERFLOW);
                    return c;
                }
                /**
                 * @dev Returns the subtraction of two unsigned integers of 256 bits, reverting on overflow.
                 */
                function sub(uint256 a, uint256 b) internal pure returns (uint256) {
                    _require(b <= a, Errors.SUB_OVERFLOW);
                    uint256 c = a - b;
                    return c;
                }
                /**
                 * @dev Returns the subtraction of two signed integers, reverting on overflow.
                 */
                function sub(int256 a, int256 b) internal pure returns (int256) {
                    int256 c = a - b;
                    _require((b >= 0 && c <= a) || (b < 0 && c > a), Errors.SUB_OVERFLOW);
                    return c;
                }
                /**
                 * @dev Returns the largest of two numbers of 256 bits.
                 */
                function max(uint256 a, uint256 b) internal pure returns (uint256) {
                    return a >= b ? a : b;
                }
                /**
                 * @dev Returns the smallest of two numbers of 256 bits.
                 */
                function min(uint256 a, uint256 b) internal pure returns (uint256) {
                    return a < b ? a : b;
                }
                function mul(uint256 a, uint256 b) internal pure returns (uint256) {
                    uint256 c = a * b;
                    _require(a == 0 || c / a == b, Errors.MUL_OVERFLOW);
                    return c;
                }
                function divDown(uint256 a, uint256 b) internal pure returns (uint256) {
                    _require(b != 0, Errors.ZERO_DIVISION);
                    return a / b;
                }
                function divUp(uint256 a, uint256 b) internal pure returns (uint256) {
                    _require(b != 0, Errors.ZERO_DIVISION);
                    if (a == 0) {
                        return 0;
                    } else {
                        return 1 + (a - 1) / b;
                    }
                }
            }
            // SPDX-License-Identifier: MIT
            pragma solidity ^0.7.0;
            // Based on the EnumerableMap library from OpenZeppelin contracts, altered to include the following:
            //  * a map from IERC20 to bytes32
            //  * entries are stored in mappings instead of arrays, reducing implicit storage reads for out-of-bounds checks
            //  * unchecked_at and unchecked_valueAt, which allow for more gas efficient data reads in some scenarios
            //  * unchecked_indexOf and unchecked_setAt, which allow for more gas efficient data writes in some scenarios
            //
            // Additionally, the base private functions that work on bytes32 were removed and replaced with a native implementation
            // for IERC20 keys, to reduce bytecode size and runtime costs.
            // We're using non-standard casing for the unchecked functions to differentiate them, so we need to turn off that rule
            // solhint-disable func-name-mixedcase
            import "./IERC20.sol";
            import "../helpers/BalancerErrors.sol";
            /**
             * @dev Library for managing an enumerable variant of Solidity's
             * https://solidity.readthedocs.io/en/latest/types.html#mapping-types[`mapping`]
             * type.
             *
             * Maps have the following properties:
             *
             * - Entries are added, removed, and checked for existence in constant time
             * (O(1)).
             * - Entries are enumerated in O(n). No guarantees are made on the ordering.
             *
             * ```
             * contract Example {
             *     // Add the library methods
             *     using EnumerableMap for EnumerableMap.UintToAddressMap;
             *
             *     // Declare a set state variable
             *     EnumerableMap.UintToAddressMap private myMap;
             * }
             * ```
             */
            library EnumerableMap {
                // The original OpenZeppelin implementation uses a generic Map type with bytes32 keys: this was replaced with
                // IERC20ToBytes32Map, which uses IERC20 keys natively, resulting in more dense bytecode.
                struct IERC20ToBytes32MapEntry {
                    IERC20 _key;
                    bytes32 _value;
                }
                struct IERC20ToBytes32Map {
                    // Number of entries in the map
                    uint256 _length;
                    // Storage of map keys and values
                    mapping(uint256 => IERC20ToBytes32MapEntry) _entries;
                    // Position of the entry defined by a key in the `entries` array, plus 1
                    // because index 0 means a key is not in the map.
                    mapping(IERC20 => uint256) _indexes;
                }
                /**
                 * @dev Adds a key-value pair to a map, or updates the value for an existing
                 * key. O(1).
                 *
                 * Returns true if the key was added to the map, that is if it was not
                 * already present.
                 */
                function set(
                    IERC20ToBytes32Map storage map,
                    IERC20 key,
                    bytes32 value
                ) internal returns (bool) {
                    // We read and store the key's index to prevent multiple reads from the same storage slot
                    uint256 keyIndex = map._indexes[key];
                    // Equivalent to !contains(map, key)
                    if (keyIndex == 0) {
                        uint256 previousLength = map._length;
                        map._entries[previousLength] = IERC20ToBytes32MapEntry({ _key: key, _value: value });
                        map._length = previousLength + 1;
                        // The entry is stored at previousLength, but we add 1 to all indexes
                        // and use 0 as a sentinel value
                        map._indexes[key] = previousLength + 1;
                        return true;
                    } else {
                        map._entries[keyIndex - 1]._value = value;
                        return false;
                    }
                }
                /**
                 * @dev Updates the value for an entry, given its key's index. The key index can be retrieved via
                 * {unchecked_indexOf}, and it should be noted that key indices may change when calling {set} or {remove}. O(1).
                 *
                 * This function performs one less storage read than {set}, but it should only be used when `index` is known to be
                 * within bounds.
                 */
                function unchecked_setAt(
                    IERC20ToBytes32Map storage map,
                    uint256 index,
                    bytes32 value
                ) internal {
                    map._entries[index]._value = value;
                }
                /**
                 * @dev Removes a key-value pair from a map. O(1).
                 *
                 * Returns true if the key was removed from the map, that is if it was present.
                 */
                function remove(IERC20ToBytes32Map storage map, IERC20 key) internal returns (bool) {
                    // We read and store the key's index to prevent multiple reads from the same storage slot
                    uint256 keyIndex = map._indexes[key];
                    // Equivalent to contains(map, key)
                    if (keyIndex != 0) {
                        // To delete a key-value pair from the _entries pseudo-array in O(1), we swap the entry to delete with the
                        // one at the highest index, and then remove this last entry (sometimes called as 'swap and pop').
                        // This modifies the order of the pseudo-array, as noted in {at}.
                        uint256 toDeleteIndex = keyIndex - 1;
                        uint256 lastIndex = map._length - 1;
                        // When the entry to delete is the last one, the swap operation is unnecessary. However, since this occurs
                        // so rarely, we still do the swap anyway to avoid the gas cost of adding an 'if' statement.
                        IERC20ToBytes32MapEntry storage lastEntry = map._entries[lastIndex];
                        // Move the last entry to the index where the entry to delete is
                        map._entries[toDeleteIndex] = lastEntry;
                        // Update the index for the moved entry
                        map._indexes[lastEntry._key] = toDeleteIndex + 1; // All indexes are 1-based
                        // Delete the slot where the moved entry was stored
                        delete map._entries[lastIndex];
                        map._length = lastIndex;
                        // Delete the index for the deleted slot
                        delete map._indexes[key];
                        return true;
                    } else {
                        return false;
                    }
                }
                /**
                 * @dev Returns true if the key is in the map. O(1).
                 */
                function contains(IERC20ToBytes32Map storage map, IERC20 key) internal view returns (bool) {
                    return map._indexes[key] != 0;
                }
                /**
                 * @dev Returns the number of key-value pairs in the map. O(1).
                 */
                function length(IERC20ToBytes32Map storage map) internal view returns (uint256) {
                    return map._length;
                }
                /**
                 * @dev Returns the key-value pair stored at position `index` in the map. O(1).
                 *
                 * Note that there are no guarantees on the ordering of entries inside the
                 * array, and it may change when more entries are added or removed.
                 *
                 * Requirements:
                 *
                 * - `index` must be strictly less than {length}.
                 */
                function at(IERC20ToBytes32Map storage map, uint256 index) internal view returns (IERC20, bytes32) {
                    _require(map._length > index, Errors.OUT_OF_BOUNDS);
                    return unchecked_at(map, index);
                }
                /**
                 * @dev Same as {at}, except this doesn't revert if `index` it outside of the map (i.e. if it is equal or larger
                 * than {length}). O(1).
                 *
                 * This function performs one less storage read than {at}, but should only be used when `index` is known to be
                 * within bounds.
                 */
                function unchecked_at(IERC20ToBytes32Map storage map, uint256 index) internal view returns (IERC20, bytes32) {
                    IERC20ToBytes32MapEntry storage entry = map._entries[index];
                    return (entry._key, entry._value);
                }
                /**
                 * @dev Same as {unchecked_At}, except it only returns the value and not the key (performing one less storage
                 * read). O(1).
                 */
                function unchecked_valueAt(IERC20ToBytes32Map storage map, uint256 index) internal view returns (bytes32) {
                    return map._entries[index]._value;
                }
                /**
                 * @dev Returns the value associated with `key`. O(1).
                 *
                 * Requirements:
                 *
                 * - `key` must be in the map. Reverts with `errorCode` otherwise.
                 */
                function get(
                    IERC20ToBytes32Map storage map,
                    IERC20 key,
                    uint256 errorCode
                ) internal view returns (bytes32) {
                    uint256 index = map._indexes[key];
                    _require(index > 0, errorCode);
                    return unchecked_valueAt(map, index - 1);
                }
                /**
                 * @dev Returns the index for `key` **plus one**. Does not revert if the key is not in the map, and returns 0
                 * instead.
                 */
                function unchecked_indexOf(IERC20ToBytes32Map storage map, IERC20 key) internal view returns (uint256) {
                    return map._indexes[key];
                }
            }
            // SPDX-License-Identifier: MIT
            pragma solidity ^0.7.0;
            import "../helpers/BalancerErrors.sol";
            // Based on the EnumerableSet library from OpenZeppelin contracts, altered to remove the base private functions that
            // work on bytes32, replacing them with a native implementation for address values, to reduce bytecode size and runtime
            // costs.
            // The `unchecked_at` function was also added, which allows for more gas efficient data reads in some scenarios.
            /**
             * @dev Library for managing
             * https://en.wikipedia.org/wiki/Set_(abstract_data_type)[sets] of primitive
             * types.
             *
             * Sets have the following properties:
             *
             * - Elements are added, removed, and checked for existence in constant time
             * (O(1)).
             * - Elements are enumerated in O(n). No guarantees are made on the ordering.
             *
             * ```
             * contract Example {
             *     // Add the library methods
             *     using EnumerableSet for EnumerableSet.AddressSet;
             *
             *     // Declare a set state variable
             *     EnumerableSet.AddressSet private mySet;
             * }
             * ```
             *
             * As of v3.3.0, sets of type `bytes32` (`Bytes32Set`), `address` (`AddressSet`)
             * and `uint256` (`UintSet`) are supported.
             */
            library EnumerableSet {
                // The original OpenZeppelin implementation uses a generic Set type with bytes32 values: this was replaced with
                // AddressSet, which uses address keys natively, resulting in more dense bytecode.
                struct AddressSet {
                    // Storage of set values
                    address[] _values;
                    // Position of the value in the `values` array, plus 1 because index 0
                    // means a value is not in the set.
                    mapping(address => uint256) _indexes;
                }
                /**
                 * @dev Add a value to a set. O(1).
                 *
                 * Returns true if the value was added to the set, that is if it was not
                 * already present.
                 */
                function add(AddressSet storage set, address value) internal returns (bool) {
                    if (!contains(set, value)) {
                        set._values.push(value);
                        // The value is stored at length-1, but we add 1 to all indexes
                        // and use 0 as a sentinel value
                        set._indexes[value] = set._values.length;
                        return true;
                    } else {
                        return false;
                    }
                }
                /**
                 * @dev Removes a value from a set. O(1).
                 *
                 * Returns true if the value was removed from the set, that is if it was
                 * present.
                 */
                function remove(AddressSet storage set, address value) internal returns (bool) {
                    // We read and store the value's index to prevent multiple reads from the same storage slot
                    uint256 valueIndex = set._indexes[value];
                    if (valueIndex != 0) {
                        // Equivalent to contains(set, value)
                        // To delete an element from the _values array in O(1), we swap the element to delete with the last one in
                        // the array, and then remove the last element (sometimes called as 'swap and pop').
                        // This modifies the order of the array, as noted in {at}.
                        uint256 toDeleteIndex = valueIndex - 1;
                        uint256 lastIndex = set._values.length - 1;
                        // When the value to delete is the last one, the swap operation is unnecessary. However, since this occurs
                        // so rarely, we still do the swap anyway to avoid the gas cost of adding an 'if' statement.
                        address lastValue = set._values[lastIndex];
                        // Move the last value to the index where the value to delete is
                        set._values[toDeleteIndex] = lastValue;
                        // Update the index for the moved value
                        set._indexes[lastValue] = toDeleteIndex + 1; // All indexes are 1-based
                        // Delete the slot where the moved value was stored
                        set._values.pop();
                        // Delete the index for the deleted slot
                        delete set._indexes[value];
                        return true;
                    } else {
                        return false;
                    }
                }
                /**
                 * @dev Returns true if the value is in the set. O(1).
                 */
                function contains(AddressSet storage set, address value) internal view returns (bool) {
                    return set._indexes[value] != 0;
                }
                /**
                 * @dev Returns the number of values on the set. O(1).
                 */
                function length(AddressSet storage set) internal view returns (uint256) {
                    return set._values.length;
                }
                /**
                 * @dev Returns the value stored at position `index` in the set. O(1).
                 *
                 * Note that there are no guarantees on the ordering of values inside the
                 * array, and it may change when more values are added or removed.
                 *
                 * Requirements:
                 *
                 * - `index` must be strictly less than {length}.
                 */
                function at(AddressSet storage set, uint256 index) internal view returns (address) {
                    _require(set._values.length > index, Errors.OUT_OF_BOUNDS);
                    return unchecked_at(set, index);
                }
                /**
                 * @dev Same as {at}, except this doesn't revert if `index` it outside of the set (i.e. if it is equal or larger
                 * than {length}). O(1).
                 *
                 * This function performs one less storage read than {at}, but should only be used when `index` is known to be
                 * within bounds.
                 */
                function unchecked_at(AddressSet storage set, uint256 index) internal view returns (address) {
                    return set._values[index];
                }
            }
            // SPDX-License-Identifier: MIT
            pragma solidity ^0.7.0;
            import "../helpers/BalancerErrors.sol";
            /**
             * @dev Wrappers over Solidity's uintXX/intXX casting operators with added overflow
             * checks.
             *
             * Downcasting from uint256/int256 in Solidity does not revert on overflow. This can
             * easily result in undesired exploitation or bugs, since developers usually
             * assume that overflows raise errors. `SafeCast` restores this intuition by
             * reverting the transaction when such an operation overflows.
             *
             * Using this library instead of the unchecked operations eliminates an entire
             * class of bugs, so it's recommended to use it always.
             *
             * Can be combined with {SafeMath} and {SignedSafeMath} to extend it to smaller types, by performing
             * all math on `uint256` and `int256` and then downcasting.
             */
            library SafeCast {
                /**
                 * @dev Converts an unsigned uint256 into a signed int256.
                 *
                 * Requirements:
                 *
                 * - input must be less than or equal to maxInt256.
                 */
                function toInt256(uint256 value) internal pure returns (int256) {
                    _require(value < 2**255, Errors.SAFE_CAST_VALUE_CANT_FIT_INT256);
                    return int256(value);
                }
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            pragma experimental ABIEncoderV2;
            import "../lib/math/Math.sol";
            import "../lib/helpers/BalancerErrors.sol";
            import "../lib/helpers/InputHelpers.sol";
            import "../lib/openzeppelin/IERC20.sol";
            import "../lib/openzeppelin/ReentrancyGuard.sol";
            import "../lib/openzeppelin/SafeERC20.sol";
            import "./Fees.sol";
            import "./PoolTokens.sol";
            import "./UserBalance.sol";
            import "./interfaces/IBasePool.sol";
            /**
             * @dev Stores the Asset Managers (by Pool and token), and implements the top level Asset Manager and Pool interfaces,
             * such as registering and deregistering tokens, joining and exiting Pools, and informational functions like `getPool`
             * and `getPoolTokens`, delegating to specialization-specific functions as needed.
             *
             * `managePoolBalance` handles all Asset Manager interactions.
             */
            abstract contract PoolBalances is Fees, ReentrancyGuard, PoolTokens, UserBalance {
                using Math for uint256;
                using SafeERC20 for IERC20;
                using BalanceAllocation for bytes32;
                using BalanceAllocation for bytes32[];
                function joinPool(
                    bytes32 poolId,
                    address sender,
                    address recipient,
                    JoinPoolRequest memory request
                ) external payable override whenNotPaused {
                    // This function doesn't have the nonReentrant modifier: it is applied to `_joinOrExit` instead.
                    // Note that `recipient` is not actually payable in the context of a join - we cast it because we handle both
                    // joins and exits at once.
                    _joinOrExit(PoolBalanceChangeKind.JOIN, poolId, sender, payable(recipient), _toPoolBalanceChange(request));
                }
                function exitPool(
                    bytes32 poolId,
                    address sender,
                    address payable recipient,
                    ExitPoolRequest memory request
                ) external override {
                    // This function doesn't have the nonReentrant modifier: it is applied to `_joinOrExit` instead.
                    _joinOrExit(PoolBalanceChangeKind.EXIT, poolId, sender, recipient, _toPoolBalanceChange(request));
                }
                // This has the exact same layout as JoinPoolRequest and ExitPoolRequest, except the `maxAmountsIn` and
                // `minAmountsOut` are called `limits`. Internally we use this struct for both since these two functions are quite
                // similar, but expose the others to callers for clarity.
                struct PoolBalanceChange {
                    IAsset[] assets;
                    uint256[] limits;
                    bytes userData;
                    bool useInternalBalance;
                }
                /**
                 * @dev Converts a JoinPoolRequest into a PoolBalanceChange, with no runtime cost.
                 */
                function _toPoolBalanceChange(JoinPoolRequest memory request)
                    private
                    pure
                    returns (PoolBalanceChange memory change)
                {
                    // solhint-disable-next-line no-inline-assembly
                    assembly {
                        change := request
                    }
                }
                /**
                 * @dev Converts an ExitPoolRequest into a PoolBalanceChange, with no runtime cost.
                 */
                function _toPoolBalanceChange(ExitPoolRequest memory request)
                    private
                    pure
                    returns (PoolBalanceChange memory change)
                {
                    // solhint-disable-next-line no-inline-assembly
                    assembly {
                        change := request
                    }
                }
                /**
                 * @dev Implements both `joinPool` and `exitPool`, based on `kind`.
                 */
                function _joinOrExit(
                    PoolBalanceChangeKind kind,
                    bytes32 poolId,
                    address sender,
                    address payable recipient,
                    PoolBalanceChange memory change
                ) private nonReentrant withRegisteredPool(poolId) authenticateFor(sender) {
                    // This function uses a large number of stack variables (poolId, sender and recipient, balances, amounts, fees,
                    // etc.), which leads to 'stack too deep' issues. It relies on private functions with seemingly arbitrary
                    // interfaces to work around this limitation.
                    InputHelpers.ensureInputLengthMatch(change.assets.length, change.limits.length);
                    // We first check that the caller passed the Pool's registered tokens in the correct order, and retrieve the
                    // current balance for each.
                    IERC20[] memory tokens = _translateToIERC20(change.assets);
                    bytes32[] memory balances = _validateTokensAndGetBalances(poolId, tokens);
                    // The bulk of the work is done here: the corresponding Pool hook is called, its final balances are computed,
                    // assets are transferred, and fees are paid.
                    (
                        bytes32[] memory finalBalances,
                        uint256[] memory amountsInOrOut,
                        uint256[] memory paidProtocolSwapFeeAmounts
                    ) = _callPoolBalanceChange(kind, poolId, sender, recipient, change, balances);
                    // All that remains is storing the new Pool balances.
                    PoolSpecialization specialization = _getPoolSpecialization(poolId);
                    if (specialization == PoolSpecialization.TWO_TOKEN) {
                        _setTwoTokenPoolCashBalances(poolId, tokens[0], finalBalances[0], tokens[1], finalBalances[1]);
                    } else if (specialization == PoolSpecialization.MINIMAL_SWAP_INFO) {
                        _setMinimalSwapInfoPoolBalances(poolId, tokens, finalBalances);
                    } else {
                        // PoolSpecialization.GENERAL
                        _setGeneralPoolBalances(poolId, finalBalances);
                    }
                    bool positive = kind == PoolBalanceChangeKind.JOIN; // Amounts in are positive, out are negative
                    emit PoolBalanceChanged(
                        poolId,
                        sender,
                        tokens,
                        // We can unsafely cast to int256 because balances are actually stored as uint112
                        _unsafeCastToInt256(amountsInOrOut, positive),
                        paidProtocolSwapFeeAmounts
                    );
                }
                /**
                 * @dev Calls the corresponding Pool hook to get the amounts in/out plus protocol fee amounts, and performs the
                 * associated token transfers and fee payments, returning the Pool's final balances.
                 */
                function _callPoolBalanceChange(
                    PoolBalanceChangeKind kind,
                    bytes32 poolId,
                    address sender,
                    address payable recipient,
                    PoolBalanceChange memory change,
                    bytes32[] memory balances
                )
                    private
                    returns (
                        bytes32[] memory finalBalances,
                        uint256[] memory amountsInOrOut,
                        uint256[] memory dueProtocolFeeAmounts
                    )
                {
                    (uint256[] memory totalBalances, uint256 lastChangeBlock) = balances.totalsAndLastChangeBlock();
                    IBasePool pool = IBasePool(_getPoolAddress(poolId));
                    (amountsInOrOut, dueProtocolFeeAmounts) = kind == PoolBalanceChangeKind.JOIN
                        ? pool.onJoinPool(
                            poolId,
                            sender,
                            recipient,
                            totalBalances,
                            lastChangeBlock,
                            _getProtocolSwapFeePercentage(),
                            change.userData
                        )
                        : pool.onExitPool(
                            poolId,
                            sender,
                            recipient,
                            totalBalances,
                            lastChangeBlock,
                            _getProtocolSwapFeePercentage(),
                            change.userData
                        );
                    InputHelpers.ensureInputLengthMatch(balances.length, amountsInOrOut.length, dueProtocolFeeAmounts.length);
                    // The Vault ignores the `recipient` in joins and the `sender` in exits: it is up to the Pool to keep track of
                    // their participation.
                    finalBalances = kind == PoolBalanceChangeKind.JOIN
                        ? _processJoinPoolTransfers(sender, change, balances, amountsInOrOut, dueProtocolFeeAmounts)
                        : _processExitPoolTransfers(recipient, change, balances, amountsInOrOut, dueProtocolFeeAmounts);
                }
                /**
                 * @dev Transfers `amountsIn` from `sender`, checking that they are within their accepted limits, and pays
                 * accumulated protocol swap fees.
                 *
                 * Returns the Pool's final balances, which are the current balances plus `amountsIn` minus accumulated protocol
                 * swap fees.
                 */
                function _processJoinPoolTransfers(
                    address sender,
                    PoolBalanceChange memory change,
                    bytes32[] memory balances,
                    uint256[] memory amountsIn,
                    uint256[] memory dueProtocolFeeAmounts
                ) private returns (bytes32[] memory finalBalances) {
                    // We need to track how much of the received ETH was used and wrapped into WETH to return any excess.
                    uint256 wrappedEth = 0;
                    finalBalances = new bytes32[](balances.length);
                    for (uint256 i = 0; i < change.assets.length; ++i) {
                        uint256 amountIn = amountsIn[i];
                        _require(amountIn <= change.limits[i], Errors.JOIN_ABOVE_MAX);
                        // Receive assets from the sender - possibly from Internal Balance.
                        IAsset asset = change.assets[i];
                        _receiveAsset(asset, amountIn, sender, change.useInternalBalance);
                        if (_isETH(asset)) {
                            wrappedEth = wrappedEth.add(amountIn);
                        }
                        uint256 feeAmount = dueProtocolFeeAmounts[i];
                        _payFeeAmount(_translateToIERC20(asset), feeAmount);
                        // Compute the new Pool balances. Note that the fee amount might be larger than `amountIn`,
                        // resulting in an overall decrease of the Pool's balance for a token.
                        finalBalances[i] = (amountIn >= feeAmount) // This lets us skip checked arithmetic
                            ? balances[i].increaseCash(amountIn - feeAmount)
                            : balances[i].decreaseCash(feeAmount - amountIn);
                    }
                    // Handle any used and remaining ETH.
                    _handleRemainingEth(wrappedEth);
                }
                /**
                 * @dev Transfers `amountsOut` to `recipient`, checking that they are within their accepted limits, and pays
                 * accumulated protocol swap fees from the Pool.
                 *
                 * Returns the Pool's final balances, which are the current `balances` minus `amountsOut` and fees paid
                 * (`dueProtocolFeeAmounts`).
                 */
                function _processExitPoolTransfers(
                    address payable recipient,
                    PoolBalanceChange memory change,
                    bytes32[] memory balances,
                    uint256[] memory amountsOut,
                    uint256[] memory dueProtocolFeeAmounts
                ) private returns (bytes32[] memory finalBalances) {
                    finalBalances = new bytes32[](balances.length);
                    for (uint256 i = 0; i < change.assets.length; ++i) {
                        uint256 amountOut = amountsOut[i];
                        _require(amountOut >= change.limits[i], Errors.EXIT_BELOW_MIN);
                        // Send tokens to the recipient - possibly to Internal Balance
                        IAsset asset = change.assets[i];
                        _sendAsset(asset, amountOut, recipient, change.useInternalBalance);
                        uint256 feeAmount = dueProtocolFeeAmounts[i];
                        _payFeeAmount(_translateToIERC20(asset), feeAmount);
                        // Compute the new Pool balances. A Pool's token balance always decreases after an exit (potentially by 0).
                        finalBalances[i] = balances[i].decreaseCash(amountOut.add(feeAmount));
                    }
                }
                /**
                 * @dev Returns the total balance for `poolId`'s `expectedTokens`.
                 *
                 * `expectedTokens` must exactly equal the token array returned by `getPoolTokens`: both arrays must have the same
                 * length, elements and order. Additionally, the Pool must have at least one registered token.
                 */
                function _validateTokensAndGetBalances(bytes32 poolId, IERC20[] memory expectedTokens)
                    private
                    view
                    returns (bytes32[] memory)
                {
                    (IERC20[] memory actualTokens, bytes32[] memory balances) = _getPoolTokens(poolId);
                    InputHelpers.ensureInputLengthMatch(actualTokens.length, expectedTokens.length);
                    _require(actualTokens.length > 0, Errors.POOL_NO_TOKENS);
                    for (uint256 i = 0; i < actualTokens.length; ++i) {
                        _require(actualTokens[i] == expectedTokens[i], Errors.TOKENS_MISMATCH);
                    }
                    return balances;
                }
                /**
                 * @dev Casts an array of uint256 to int256, setting the sign of the result according to the `positive` flag,
                 * without checking whether the values fit in the signed 256 bit range.
                 */
                function _unsafeCastToInt256(uint256[] memory values, bool positive)
                    private
                    pure
                    returns (int256[] memory signedValues)
                {
                    signedValues = new int256[](values.length);
                    for (uint256 i = 0; i < values.length; i++) {
                        signedValues[i] = positive ? int256(values[i]) : -int256(values[i]);
                    }
                }
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            pragma experimental ABIEncoderV2;
            import "../../lib/openzeppelin/IERC20.sol";
            import "./IVault.sol";
            interface IPoolSwapStructs {
                // This is not really an interface - it just defines common structs used by other interfaces: IGeneralPool and
                // IMinimalSwapInfoPool.
                //
                // This data structure represents a request for a token swap, where `kind` indicates the swap type ('given in' or
                // 'given out') which indicates whether or not the amount sent by the pool is known.
                //
                // The pool receives `tokenIn` and sends `tokenOut`. `amount` is the number of `tokenIn` tokens the pool will take
                // in, or the number of `tokenOut` tokens the Pool will send out, depending on the given swap `kind`.
                //
                // All other fields are not strictly necessary for most swaps, but are provided to support advanced scenarios in
                // some Pools.
                //
                // `poolId` is the ID of the Pool involved in the swap - this is useful for Pool contracts that implement more than
                // one Pool.
                //
                // The meaning of `lastChangeBlock` depends on the Pool specialization:
                //  - Two Token or Minimal Swap Info: the last block in which either `tokenIn` or `tokenOut` changed its total
                //    balance.
                //  - General: the last block in which *any* of the Pool's registered tokens changed its total balance.
                //
                // `from` is the origin address for the funds the Pool receives, and `to` is the destination address
                // where the Pool sends the outgoing tokens.
                //
                // `userData` is extra data provided by the caller - typically a signature from a trusted party.
                struct SwapRequest {
                    IVault.SwapKind kind;
                    IERC20 tokenIn;
                    IERC20 tokenOut;
                    uint256 amount;
                    // Misc data
                    bytes32 poolId;
                    uint256 lastChangeBlock;
                    address from;
                    address to;
                    bytes userData;
                }
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            pragma experimental ABIEncoderV2;
            import "./IBasePool.sol";
            /**
             * @dev IPools with the General specialization setting should implement this interface.
             *
             * This is called by the Vault when a user calls `IVault.swap` or `IVault.batchSwap` to swap with this Pool.
             * Returns the number of tokens the Pool will grant to the user in a 'given in' swap, or that the user will
             * grant to the pool in a 'given out' swap.
             *
             * This can often be implemented by a `view` function, since many pricing algorithms don't need to track state
             * changes in swaps. However, contracts implementing this in non-view functions should check that the caller is
             * indeed the Vault.
             */
            interface IGeneralPool is IBasePool {
                function onSwap(
                    SwapRequest memory swapRequest,
                    uint256[] memory balances,
                    uint256 indexIn,
                    uint256 indexOut
                ) external returns (uint256 amount);
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            pragma experimental ABIEncoderV2;
            import "./IBasePool.sol";
            /**
             * @dev Pool contracts with the MinimalSwapInfo or TwoToken specialization settings should implement this interface.
             *
             * This is called by the Vault when a user calls `IVault.swap` or `IVault.batchSwap` to swap with this Pool.
             * Returns the number of tokens the Pool will grant to the user in a 'given in' swap, or that the user will grant
             * to the pool in a 'given out' swap.
             *
             * This can often be implemented by a `view` function, since many pricing algorithms don't need to track state
             * changes in swaps. However, contracts implementing this in non-view functions should check that the caller is
             * indeed the Vault.
             */
            interface IMinimalSwapInfoPool is IBasePool {
                function onSwap(
                    SwapRequest memory swapRequest,
                    uint256 currentBalanceTokenIn,
                    uint256 currentBalanceTokenOut
                ) external returns (uint256 amount);
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            import "../../lib/math/Math.sol";
            // This library is used to create a data structure that represents a token's balance for a Pool. 'cash' is how many
            // tokens the Pool has sitting inside of the Vault. 'managed' is how many tokens were withdrawn from the Vault by the
            // Pool's Asset Manager. 'total' is the sum of these two, and represents the Pool's total token balance, including
            // tokens that are *not* inside of the Vault.
            //
            // 'cash' is updated whenever tokens enter and exit the Vault, while 'managed' is only updated if the reason tokens are
            // moving is due to an Asset Manager action. This is reflected in the different methods available: 'increaseCash'
            // and 'decreaseCash' for swaps and add/remove liquidity events, and 'cashToManaged' and 'managedToCash' for events
            // transferring funds to and from the Asset Manager.
            //
            // The Vault disallows the Pool's 'cash' from becoming negative. In other words, it can never use any tokens that are
            // not inside the Vault.
            //
            // One of the goals of this library is to store the entire token balance in a single storage slot, which is why we use
            // 112 bit unsigned integers for 'cash' and 'managed'. For consistency, we also disallow any combination of 'cash' and
            // 'managed' that yields a 'total' that doesn't fit in 112 bits.
            //
            // The remaining 32 bits of the slot are used to store the most recent block when the total balance changed. This
            // can be used to implement price oracles that are resilient to 'sandwich' attacks.
            //
            // We could use a Solidity struct to pack these three values together in a single storage slot, but unfortunately
            // Solidity only allows for structs to live in either storage, calldata or memory. Because a memory struct still takes
            // up a slot in the stack (to store its memory location), and because the entire balance fits in a single stack slot
            // (two 112 bit values plus the 32 bit block), using memory is strictly less gas performant. Therefore, we do manual
            // packing and unpacking.
            //
            // Since we cannot define new types, we rely on bytes32 to represent these values instead, as it doesn't have any
            // associated arithmetic operations and therefore reduces the chance of misuse.
            library BalanceAllocation {
                using Math for uint256;
                // The 'cash' portion of the balance is stored in the least significant 112 bits of a 256 bit word, while the
                // 'managed' part uses the following 112 bits. The most significant 32 bits are used to store the block
                /**
                 * @dev Returns the total amount of Pool tokens, including those that are not currently in the Vault ('managed').
                 */
                function total(bytes32 balance) internal pure returns (uint256) {
                    // Since 'cash' and 'managed' are 112 bit values, we don't need checked arithmetic. Additionally, `toBalance`
                    // ensures that 'total' always fits in 112 bits.
                    return cash(balance) + managed(balance);
                }
                /**
                 * @dev Returns the amount of Pool tokens currently in the Vault.
                 */
                function cash(bytes32 balance) internal pure returns (uint256) {
                    uint256 mask = 2**(112) - 1;
                    return uint256(balance) & mask;
                }
                /**
                 * @dev Returns the amount of Pool tokens that are being managed by an Asset Manager.
                 */
                function managed(bytes32 balance) internal pure returns (uint256) {
                    uint256 mask = 2**(112) - 1;
                    return uint256(balance >> 112) & mask;
                }
                /**
                 * @dev Returns the last block when the total balance changed.
                 */
                function lastChangeBlock(bytes32 balance) internal pure returns (uint256) {
                    uint256 mask = 2**(32) - 1;
                    return uint256(balance >> 224) & mask;
                }
                /**
                 * @dev Returns the difference in 'managed' between two balances.
                 */
                function managedDelta(bytes32 newBalance, bytes32 oldBalance) internal pure returns (int256) {
                    // Because `managed` is a 112 bit value, we can safely perform unchecked arithmetic in 256 bits.
                    return int256(managed(newBalance)) - int256(managed(oldBalance));
                }
                /**
                 * @dev Returns the total balance for each entry in `balances`, as well as the latest block when the total
                 * balance of *any* of them last changed.
                 */
                function totalsAndLastChangeBlock(bytes32[] memory balances)
                    internal
                    pure
                    returns (
                        uint256[] memory results,
                        uint256 lastChangeBlock_ // Avoid shadowing
                    )
                {
                    results = new uint256[](balances.length);
                    lastChangeBlock_ = 0;
                    for (uint256 i = 0; i < results.length; i++) {
                        bytes32 balance = balances[i];
                        results[i] = total(balance);
                        lastChangeBlock_ = Math.max(lastChangeBlock_, lastChangeBlock(balance));
                    }
                }
                /**
                 * @dev Returns true if `balance`'s 'total' balance is zero. Costs less gas than computing 'total' and comparing
                 * with zero.
                 */
                function isZero(bytes32 balance) internal pure returns (bool) {
                    // We simply need to check the least significant 224 bytes of the word: the block does not affect this.
                    uint256 mask = 2**(224) - 1;
                    return (uint256(balance) & mask) == 0;
                }
                /**
                 * @dev Returns true if `balance`'s 'total' balance is not zero. Costs less gas than computing 'total' and comparing
                 * with zero.
                 */
                function isNotZero(bytes32 balance) internal pure returns (bool) {
                    return !isZero(balance);
                }
                /**
                 * @dev Packs together `cash` and `managed` amounts with a block to create a balance value.
                 *
                 * For consistency, this also checks that the sum of `cash` and `managed` (`total`) fits in 112 bits.
                 */
                function toBalance(
                    uint256 _cash,
                    uint256 _managed,
                    uint256 _blockNumber
                ) internal pure returns (bytes32) {
                    uint256 _total = _cash + _managed;
                    // Since both 'cash' and 'managed' are positive integers, by checking that their sum ('total') fits in 112 bits
                    // we are also indirectly checking that both 'cash' and 'managed' themselves fit in 112 bits.
                    _require(_total >= _cash && _total < 2**112, Errors.BALANCE_TOTAL_OVERFLOW);
                    // We assume the block fits in 32 bits - this is expected to hold for at least a few decades.
                    return _pack(_cash, _managed, _blockNumber);
                }
                /**
                 * @dev Increases a Pool's 'cash' (and therefore its 'total'). Called when Pool tokens are sent to the Vault (except
                 * for Asset Manager deposits).
                 *
                 * Updates the last total balance change block, even if `amount` is zero.
                 */
                function increaseCash(bytes32 balance, uint256 amount) internal view returns (bytes32) {
                    uint256 newCash = cash(balance).add(amount);
                    uint256 currentManaged = managed(balance);
                    uint256 newLastChangeBlock = block.number;
                    return toBalance(newCash, currentManaged, newLastChangeBlock);
                }
                /**
                 * @dev Decreases a Pool's 'cash' (and therefore its 'total'). Called when Pool tokens are sent from the Vault
                 * (except for Asset Manager withdrawals).
                 *
                 * Updates the last total balance change block, even if `amount` is zero.
                 */
                function decreaseCash(bytes32 balance, uint256 amount) internal view returns (bytes32) {
                    uint256 newCash = cash(balance).sub(amount);
                    uint256 currentManaged = managed(balance);
                    uint256 newLastChangeBlock = block.number;
                    return toBalance(newCash, currentManaged, newLastChangeBlock);
                }
                /**
                 * @dev Moves 'cash' into 'managed', leaving 'total' unchanged. Called when an Asset Manager withdraws Pool tokens
                 * from the Vault.
                 */
                function cashToManaged(bytes32 balance, uint256 amount) internal pure returns (bytes32) {
                    uint256 newCash = cash(balance).sub(amount);
                    uint256 newManaged = managed(balance).add(amount);
                    uint256 currentLastChangeBlock = lastChangeBlock(balance);
                    return toBalance(newCash, newManaged, currentLastChangeBlock);
                }
                /**
                 * @dev Moves 'managed' into 'cash', leaving 'total' unchanged. Called when an Asset Manager deposits Pool tokens
                 * into the Vault.
                 */
                function managedToCash(bytes32 balance, uint256 amount) internal pure returns (bytes32) {
                    uint256 newCash = cash(balance).add(amount);
                    uint256 newManaged = managed(balance).sub(amount);
                    uint256 currentLastChangeBlock = lastChangeBlock(balance);
                    return toBalance(newCash, newManaged, currentLastChangeBlock);
                }
                /**
                 * @dev Sets 'managed' balance to an arbitrary value, changing 'total'. Called when the Asset Manager reports
                 * profits or losses. It's the Manager's responsibility to provide a meaningful value.
                 *
                 * Updates the last total balance change block, even if `newManaged` is equal to the current 'managed' value.
                 */
                function setManaged(bytes32 balance, uint256 newManaged) internal view returns (bytes32) {
                    uint256 currentCash = cash(balance);
                    uint256 newLastChangeBlock = block.number;
                    return toBalance(currentCash, newManaged, newLastChangeBlock);
                }
                // Alternative mode for Pools with the Two Token specialization setting
                // Instead of storing cash and external for each 'token in' a single storage slot, Two Token Pools store the cash
                // for both tokens in the same slot, and the managed for both in another one. This reduces the gas cost for swaps,
                // because the only slot that needs to be updated is the one with the cash. However, it also means that managing
                // balances is more cumbersome, as both tokens need to be read/written at the same time.
                //
                // The field with both cash balances packed is called sharedCash, and the one with external amounts is called
                // sharedManaged. These two are collectively called the 'shared' balance fields. In both of these, the portion
                // that corresponds to token A is stored in the least significant 112 bits of a 256 bit word, while token B's part
                // uses the next least significant 112 bits.
                //
                // Because only cash is written to during a swap, we store the last total balance change block with the
                // packed cash fields. Typically Pools have a distinct block per token: in the case of Two Token Pools they
                // are the same.
                /**
                 * @dev Extracts the part of the balance that corresponds to token A. This function can be used to decode both
                 * shared cash and managed balances.
                 */
                function _decodeBalanceA(bytes32 sharedBalance) private pure returns (uint256) {
                    uint256 mask = 2**(112) - 1;
                    return uint256(sharedBalance) & mask;
                }
                /**
                 * @dev Extracts the part of the balance that corresponds to token B. This function can be used to decode both
                 * shared cash and managed balances.
                 */
                function _decodeBalanceB(bytes32 sharedBalance) private pure returns (uint256) {
                    uint256 mask = 2**(112) - 1;
                    return uint256(sharedBalance >> 112) & mask;
                }
                // To decode the last balance change block, we can simply use the `blockNumber` function.
                /**
                 * @dev Unpacks the shared token A and token B cash and managed balances into the balance for token A.
                 */
                function fromSharedToBalanceA(bytes32 sharedCash, bytes32 sharedManaged) internal pure returns (bytes32) {
                    // Note that we extract the block from the sharedCash field, which is the one that is updated by swaps.
                    // Both token A and token B use the same block
                    return toBalance(_decodeBalanceA(sharedCash), _decodeBalanceA(sharedManaged), lastChangeBlock(sharedCash));
                }
                /**
                 * @dev Unpacks the shared token A and token B cash and managed balances into the balance for token B.
                 */
                function fromSharedToBalanceB(bytes32 sharedCash, bytes32 sharedManaged) internal pure returns (bytes32) {
                    // Note that we extract the block from the sharedCash field, which is the one that is updated by swaps.
                    // Both token A and token B use the same block
                    return toBalance(_decodeBalanceB(sharedCash), _decodeBalanceB(sharedManaged), lastChangeBlock(sharedCash));
                }
                /**
                 * @dev Returns the sharedCash shared field, given the current balances for token A and token B.
                 */
                function toSharedCash(bytes32 tokenABalance, bytes32 tokenBBalance) internal pure returns (bytes32) {
                    // Both balances are assigned the same block  Since it is possible a single one of them has changed (for
                    // example, in an Asset Manager update), we keep the latest (largest) one.
                    uint32 newLastChangeBlock = uint32(Math.max(lastChangeBlock(tokenABalance), lastChangeBlock(tokenBBalance)));
                    return _pack(cash(tokenABalance), cash(tokenBBalance), newLastChangeBlock);
                }
                /**
                 * @dev Returns the sharedManaged shared field, given the current balances for token A and token B.
                 */
                function toSharedManaged(bytes32 tokenABalance, bytes32 tokenBBalance) internal pure returns (bytes32) {
                    // We don't bother storing a last change block, as it is read from the shared cash field.
                    return _pack(managed(tokenABalance), managed(tokenBBalance), 0);
                }
                // Shared functions
                /**
                 * @dev Packs together two uint112 and one uint32 into a bytes32
                 */
                function _pack(
                    uint256 _leastSignificant,
                    uint256 _midSignificant,
                    uint256 _mostSignificant
                ) private pure returns (bytes32) {
                    return bytes32((_mostSignificant << 224) + (_midSignificant << 112) + _leastSignificant);
                }
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            pragma experimental ABIEncoderV2;
            import "../lib/helpers/BalancerErrors.sol";
            import "../lib/openzeppelin/ReentrancyGuard.sol";
            import "./AssetManagers.sol";
            import "./PoolRegistry.sol";
            import "./balances/BalanceAllocation.sol";
            abstract contract PoolTokens is ReentrancyGuard, PoolRegistry, AssetManagers {
                using BalanceAllocation for bytes32;
                using BalanceAllocation for bytes32[];
                function registerTokens(
                    bytes32 poolId,
                    IERC20[] memory tokens,
                    address[] memory assetManagers
                ) external override nonReentrant whenNotPaused onlyPool(poolId) {
                    InputHelpers.ensureInputLengthMatch(tokens.length, assetManagers.length);
                    // Validates token addresses and assigns Asset Managers
                    for (uint256 i = 0; i < tokens.length; ++i) {
                        IERC20 token = tokens[i];
                        _require(token != IERC20(0), Errors.INVALID_TOKEN);
                        _poolAssetManagers[poolId][token] = assetManagers[i];
                    }
                    PoolSpecialization specialization = _getPoolSpecialization(poolId);
                    if (specialization == PoolSpecialization.TWO_TOKEN) {
                        _require(tokens.length == 2, Errors.TOKENS_LENGTH_MUST_BE_2);
                        _registerTwoTokenPoolTokens(poolId, tokens[0], tokens[1]);
                    } else if (specialization == PoolSpecialization.MINIMAL_SWAP_INFO) {
                        _registerMinimalSwapInfoPoolTokens(poolId, tokens);
                    } else {
                        // PoolSpecialization.GENERAL
                        _registerGeneralPoolTokens(poolId, tokens);
                    }
                    emit TokensRegistered(poolId, tokens, assetManagers);
                }
                function deregisterTokens(bytes32 poolId, IERC20[] memory tokens)
                    external
                    override
                    nonReentrant
                    whenNotPaused
                    onlyPool(poolId)
                {
                    PoolSpecialization specialization = _getPoolSpecialization(poolId);
                    if (specialization == PoolSpecialization.TWO_TOKEN) {
                        _require(tokens.length == 2, Errors.TOKENS_LENGTH_MUST_BE_2);
                        _deregisterTwoTokenPoolTokens(poolId, tokens[0], tokens[1]);
                    } else if (specialization == PoolSpecialization.MINIMAL_SWAP_INFO) {
                        _deregisterMinimalSwapInfoPoolTokens(poolId, tokens);
                    } else {
                        // PoolSpecialization.GENERAL
                        _deregisterGeneralPoolTokens(poolId, tokens);
                    }
                    // The deregister calls above ensure the total token balance is zero. Therefore it is now safe to remove any
                    // associated Asset Managers, since they hold no Pool balance.
                    for (uint256 i = 0; i < tokens.length; ++i) {
                        delete _poolAssetManagers[poolId][tokens[i]];
                    }
                    emit TokensDeregistered(poolId, tokens);
                }
                function getPoolTokens(bytes32 poolId)
                    external
                    view
                    override
                    withRegisteredPool(poolId)
                    returns (
                        IERC20[] memory tokens,
                        uint256[] memory balances,
                        uint256 lastChangeBlock
                    )
                {
                    bytes32[] memory rawBalances;
                    (tokens, rawBalances) = _getPoolTokens(poolId);
                    (balances, lastChangeBlock) = rawBalances.totalsAndLastChangeBlock();
                }
                function getPoolTokenInfo(bytes32 poolId, IERC20 token)
                    external
                    view
                    override
                    withRegisteredPool(poolId)
                    returns (
                        uint256 cash,
                        uint256 managed,
                        uint256 lastChangeBlock,
                        address assetManager
                    )
                {
                    bytes32 balance;
                    PoolSpecialization specialization = _getPoolSpecialization(poolId);
                    if (specialization == PoolSpecialization.TWO_TOKEN) {
                        balance = _getTwoTokenPoolBalance(poolId, token);
                    } else if (specialization == PoolSpecialization.MINIMAL_SWAP_INFO) {
                        balance = _getMinimalSwapInfoPoolBalance(poolId, token);
                    } else {
                        // PoolSpecialization.GENERAL
                        balance = _getGeneralPoolBalance(poolId, token);
                    }
                    cash = balance.cash();
                    managed = balance.managed();
                    lastChangeBlock = balance.lastChangeBlock();
                    assetManager = _poolAssetManagers[poolId][token];
                }
                /**
                 * @dev Returns all of `poolId`'s registered tokens, along with their raw balances.
                 */
                function _getPoolTokens(bytes32 poolId) internal view returns (IERC20[] memory tokens, bytes32[] memory balances) {
                    PoolSpecialization specialization = _getPoolSpecialization(poolId);
                    if (specialization == PoolSpecialization.TWO_TOKEN) {
                        return _getTwoTokenPoolTokens(poolId);
                    } else if (specialization == PoolSpecialization.MINIMAL_SWAP_INFO) {
                        return _getMinimalSwapInfoPoolTokens(poolId);
                    } else {
                        // PoolSpecialization.GENERAL
                        return _getGeneralPoolTokens(poolId);
                    }
                }
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            pragma experimental ABIEncoderV2;
            import "../lib/helpers/BalancerErrors.sol";
            import "../lib/math/Math.sol";
            import "../lib/openzeppelin/IERC20.sol";
            import "../lib/openzeppelin/ReentrancyGuard.sol";
            import "../lib/openzeppelin/SafeCast.sol";
            import "../lib/openzeppelin/SafeERC20.sol";
            import "./AssetTransfersHandler.sol";
            import "./VaultAuthorization.sol";
            /**
             * Implement User Balance interactions, which combine Internal Balance and using the Vault's ERC20 allowance.
             *
             * Users can deposit tokens into the Vault, where they are allocated to their Internal Balance, and later
             * transferred or withdrawn. It can also be used as a source of tokens when joining Pools, as a destination
             * when exiting them, and as either when performing swaps. This usage of Internal Balance results in greatly reduced
             * gas costs when compared to relying on plain ERC20 transfers, leading to large savings for frequent users.
             *
             * Internal Balance management features batching, which means a single contract call can be used to perform multiple
             * operations of different kinds, with different senders and recipients, at once.
             */
            abstract contract UserBalance is ReentrancyGuard, AssetTransfersHandler, VaultAuthorization {
                using Math for uint256;
                using SafeCast for uint256;
                using SafeERC20 for IERC20;
                // Internal Balance for each token, for each account.
                mapping(address => mapping(IERC20 => uint256)) private _internalTokenBalance;
                function getInternalBalance(address user, IERC20[] memory tokens)
                    external
                    view
                    override
                    returns (uint256[] memory balances)
                {
                    balances = new uint256[](tokens.length);
                    for (uint256 i = 0; i < tokens.length; i++) {
                        balances[i] = _getInternalBalance(user, tokens[i]);
                    }
                }
                function manageUserBalance(UserBalanceOp[] memory ops) external payable override nonReentrant {
                    // We need to track how much of the received ETH was used and wrapped into WETH to return any excess.
                    uint256 ethWrapped = 0;
                    // Cache for these checks so we only perform them once (if at all).
                    bool checkedCallerIsRelayer = false;
                    bool checkedNotPaused = false;
                    for (uint256 i = 0; i < ops.length; i++) {
                        UserBalanceOpKind kind;
                        IAsset asset;
                        uint256 amount;
                        address sender;
                        address payable recipient;
                        // This destructuring by calling `_validateUserBalanceOp` seems odd, but results in reduced bytecode size.
                        (kind, asset, amount, sender, recipient, checkedCallerIsRelayer) = _validateUserBalanceOp(
                            ops[i],
                            checkedCallerIsRelayer
                        );
                        if (kind == UserBalanceOpKind.WITHDRAW_INTERNAL) {
                            // Internal Balance withdrawals can always be performed by an authorized account.
                            _withdrawFromInternalBalance(asset, sender, recipient, amount);
                        } else {
                            // All other operations are blocked if the contract is paused.
                            // We cache the result of the pause check and skip it for other operations in this same transaction
                            // (if any).
                            if (!checkedNotPaused) {
                                _ensureNotPaused();
                                checkedNotPaused = true;
                            }
                            if (kind == UserBalanceOpKind.DEPOSIT_INTERNAL) {
                                _depositToInternalBalance(asset, sender, recipient, amount);
                                // Keep track of all ETH wrapped into WETH as part of a deposit.
                                if (_isETH(asset)) {
                                    ethWrapped = ethWrapped.add(amount);
                                }
                            } else {
                                // Transfers don't support ETH.
                                _require(!_isETH(asset), Errors.CANNOT_USE_ETH_SENTINEL);
                                IERC20 token = _asIERC20(asset);
                                if (kind == UserBalanceOpKind.TRANSFER_INTERNAL) {
                                    _transferInternalBalance(token, sender, recipient, amount);
                                } else {
                                    // TRANSFER_EXTERNAL
                                    _transferToExternalBalance(token, sender, recipient, amount);
                                }
                            }
                        }
                    }
                    // Handle any remaining ETH.
                    _handleRemainingEth(ethWrapped);
                }
                function _depositToInternalBalance(
                    IAsset asset,
                    address sender,
                    address recipient,
                    uint256 amount
                ) private {
                    _increaseInternalBalance(recipient, _translateToIERC20(asset), amount);
                    _receiveAsset(asset, amount, sender, false);
                }
                function _withdrawFromInternalBalance(
                    IAsset asset,
                    address sender,
                    address payable recipient,
                    uint256 amount
                ) private {
                    // A partial decrease of Internal Balance is disallowed: `sender` must have the full `amount`.
                    _decreaseInternalBalance(sender, _translateToIERC20(asset), amount, false);
                    _sendAsset(asset, amount, recipient, false);
                }
                function _transferInternalBalance(
                    IERC20 token,
                    address sender,
                    address recipient,
                    uint256 amount
                ) private {
                    // A partial decrease of Internal Balance is disallowed: `sender` must have the full `amount`.
                    _decreaseInternalBalance(sender, token, amount, false);
                    _increaseInternalBalance(recipient, token, amount);
                }
                function _transferToExternalBalance(
                    IERC20 token,
                    address sender,
                    address recipient,
                    uint256 amount
                ) private {
                    if (amount > 0) {
                        token.safeTransferFrom(sender, recipient, amount);
                        emit ExternalBalanceTransfer(token, sender, recipient, amount);
                    }
                }
                /**
                 * @dev Increases `account`'s Internal Balance for `token` by `amount`.
                 */
                function _increaseInternalBalance(
                    address account,
                    IERC20 token,
                    uint256 amount
                ) internal override {
                    uint256 currentBalance = _getInternalBalance(account, token);
                    uint256 newBalance = currentBalance.add(amount);
                    _setInternalBalance(account, token, newBalance, amount.toInt256());
                }
                /**
                 * @dev Decreases `account`'s Internal Balance for `token` by `amount`. If `allowPartial` is true, this function
                 * doesn't revert if `account` doesn't have enough balance, and sets it to zero and returns the deducted amount
                 * instead.
                 */
                function _decreaseInternalBalance(
                    address account,
                    IERC20 token,
                    uint256 amount,
                    bool allowPartial
                ) internal override returns (uint256 deducted) {
                    uint256 currentBalance = _getInternalBalance(account, token);
                    _require(allowPartial || (currentBalance >= amount), Errors.INSUFFICIENT_INTERNAL_BALANCE);
                    deducted = Math.min(currentBalance, amount);
                    // By construction, `deducted` is lower or equal to `currentBalance`, so we don't need to use checked
                    // arithmetic.
                    uint256 newBalance = currentBalance - deducted;
                    _setInternalBalance(account, token, newBalance, -(deducted.toInt256()));
                }
                /**
                 * @dev Sets `account`'s Internal Balance for `token` to `newBalance`.
                 *
                 * Emits an `InternalBalanceChanged` event. This event includes `delta`, which is the amount the balance increased
                 * (if positive) or decreased (if negative). To avoid reading the current balance in order to compute the delta,
                 * this function relies on the caller providing it directly.
                 */
                function _setInternalBalance(
                    address account,
                    IERC20 token,
                    uint256 newBalance,
                    int256 delta
                ) private {
                    _internalTokenBalance[account][token] = newBalance;
                    emit InternalBalanceChanged(account, token, delta);
                }
                /**
                 * @dev Returns `account`'s Internal Balance for `token`.
                 */
                function _getInternalBalance(address account, IERC20 token) internal view returns (uint256) {
                    return _internalTokenBalance[account][token];
                }
                /**
                 * @dev Destructures a User Balance operation, validating that the contract caller is allowed to perform it.
                 */
                function _validateUserBalanceOp(UserBalanceOp memory op, bool checkedCallerIsRelayer)
                    private
                    view
                    returns (
                        UserBalanceOpKind,
                        IAsset,
                        uint256,
                        address,
                        address payable,
                        bool
                    )
                {
                    // The only argument we need to validate is `sender`, which can only be either the contract caller, or a
                    // relayer approved by `sender`.
                    address sender = op.sender;
                    if (sender != msg.sender) {
                        // We need to check both that the contract caller is a relayer, and that `sender` approved them.
                        // Because the relayer check is global (i.e. independent of `sender`), we cache that result and skip it for
                        // other operations in this same transaction (if any).
                        if (!checkedCallerIsRelayer) {
                            _authenticateCaller();
                            checkedCallerIsRelayer = true;
                        }
                        _require(_hasApprovedRelayer(sender, msg.sender), Errors.USER_DOESNT_ALLOW_RELAYER);
                    }
                    return (op.kind, op.asset, op.amount, sender, op.recipient, checkedCallerIsRelayer);
                }
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            pragma experimental ABIEncoderV2;
            import "./IVault.sol";
            import "./IPoolSwapStructs.sol";
            /**
             * @dev Interface for adding and removing liquidity that all Pool contracts should implement. Note that this is not
             * the complete Pool contract interface, as it is missing the swap hooks. Pool contracts should also inherit from
             * either IGeneralPool or IMinimalSwapInfoPool
             */
            interface IBasePool is IPoolSwapStructs {
                /**
                 * @dev Called by the Vault when a user calls `IVault.joinPool` to add liquidity to this Pool. Returns how many of
                 * each registered token the user should provide, as well as the amount of protocol fees the Pool owes to the Vault.
                 * The Vault will then take tokens from `sender` and add them to the Pool's balances, as well as collect
                 * the reported amount in protocol fees, which the pool should calculate based on `protocolSwapFeePercentage`.
                 *
                 * Protocol fees are reported and charged on join events so that the Pool is free of debt whenever new users join.
                 *
                 * `sender` is the account performing the join (from which tokens will be withdrawn), and `recipient` is the account
                 * designated to receive any benefits (typically pool shares). `currentBalances` contains the total balances
                 * for each token the Pool registered in the Vault, in the same order that `IVault.getPoolTokens` would return.
                 *
                 * `lastChangeBlock` is the last block in which *any* of the Pool's registered tokens last changed its total
                 * balance.
                 *
                 * `userData` contains any pool-specific instructions needed to perform the calculations, such as the type of
                 * join (e.g., proportional given an amount of pool shares, single-asset, multi-asset, etc.)
                 *
                 * Contracts implementing this function should check that the caller is indeed the Vault before performing any
                 * state-changing operations, such as minting pool shares.
                 */
                function onJoinPool(
                    bytes32 poolId,
                    address sender,
                    address recipient,
                    uint256[] memory balances,
                    uint256 lastChangeBlock,
                    uint256 protocolSwapFeePercentage,
                    bytes memory userData
                ) external returns (uint256[] memory amountsIn, uint256[] memory dueProtocolFeeAmounts);
                /**
                 * @dev Called by the Vault when a user calls `IVault.exitPool` to remove liquidity from this Pool. Returns how many
                 * tokens the Vault should deduct from the Pool's balances, as well as the amount of protocol fees the Pool owes
                 * to the Vault. The Vault will then take tokens from the Pool's balances and send them to `recipient`,
                 * as well as collect the reported amount in protocol fees, which the Pool should calculate based on
                 * `protocolSwapFeePercentage`.
                 *
                 * Protocol fees are charged on exit events to guarantee that users exiting the Pool have paid their share.
                 *
                 * `sender` is the account performing the exit (typically the pool shareholder), and `recipient` is the account
                 * to which the Vault will send the proceeds. `currentBalances` contains the total token balances for each token
                 * the Pool registered in the Vault, in the same order that `IVault.getPoolTokens` would return.
                 *
                 * `lastChangeBlock` is the last block in which *any* of the Pool's registered tokens last changed its total
                 * balance.
                 *
                 * `userData` contains any pool-specific instructions needed to perform the calculations, such as the type of
                 * exit (e.g., proportional given an amount of pool shares, single-asset, multi-asset, etc.)
                 *
                 * Contracts implementing this function should check that the caller is indeed the Vault before performing any
                 * state-changing operations, such as burning pool shares.
                 */
                function onExitPool(
                    bytes32 poolId,
                    address sender,
                    address recipient,
                    uint256[] memory balances,
                    uint256 lastChangeBlock,
                    uint256 protocolSwapFeePercentage,
                    bytes memory userData
                ) external returns (uint256[] memory amountsOut, uint256[] memory dueProtocolFeeAmounts);
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            pragma experimental ABIEncoderV2;
            import "../lib/math/Math.sol";
            import "../lib/helpers/BalancerErrors.sol";
            import "../lib/helpers/InputHelpers.sol";
            import "../lib/openzeppelin/IERC20.sol";
            import "../lib/openzeppelin/SafeERC20.sol";
            import "../lib/openzeppelin/ReentrancyGuard.sol";
            import "./UserBalance.sol";
            import "./balances/BalanceAllocation.sol";
            import "./balances/GeneralPoolsBalance.sol";
            import "./balances/MinimalSwapInfoPoolsBalance.sol";
            import "./balances/TwoTokenPoolsBalance.sol";
            abstract contract AssetManagers is
                ReentrancyGuard,
                GeneralPoolsBalance,
                MinimalSwapInfoPoolsBalance,
                TwoTokenPoolsBalance
            {
                using Math for uint256;
                using SafeERC20 for IERC20;
                // Stores the Asset Manager for each token of each Pool.
                mapping(bytes32 => mapping(IERC20 => address)) internal _poolAssetManagers;
                function managePoolBalance(PoolBalanceOp[] memory ops) external override nonReentrant whenNotPaused {
                    // This variable could be declared inside the loop, but that causes the compiler to allocate memory on each
                    // loop iteration, increasing gas costs.
                    PoolBalanceOp memory op;
                    for (uint256 i = 0; i < ops.length; ++i) {
                        // By indexing the array only once, we don't spend extra gas in the same bounds check.
                        op = ops[i];
                        bytes32 poolId = op.poolId;
                        _ensureRegisteredPool(poolId);
                        IERC20 token = op.token;
                        _require(_isTokenRegistered(poolId, token), Errors.TOKEN_NOT_REGISTERED);
                        _require(_poolAssetManagers[poolId][token] == msg.sender, Errors.SENDER_NOT_ASSET_MANAGER);
                        PoolBalanceOpKind kind = op.kind;
                        uint256 amount = op.amount;
                        (int256 cashDelta, int256 managedDelta) = _performPoolManagementOperation(kind, poolId, token, amount);
                        emit PoolBalanceManaged(poolId, msg.sender, token, cashDelta, managedDelta);
                    }
                }
                /**
                 * @dev Performs the `kind` Asset Manager operation on a Pool.
                 *
                 * Withdrawals will transfer `amount` tokens to the caller, deposits will transfer `amount` tokens from the caller,
                 * and updates will set the managed balance to `amount`.
                 *
                 * Returns a tuple with the 'cash' and 'managed' balance deltas as a result of this call.
                 */
                function _performPoolManagementOperation(
                    PoolBalanceOpKind kind,
                    bytes32 poolId,
                    IERC20 token,
                    uint256 amount
                ) private returns (int256, int256) {
                    PoolSpecialization specialization = _getPoolSpecialization(poolId);
                    if (kind == PoolBalanceOpKind.WITHDRAW) {
                        return _withdrawPoolBalance(poolId, specialization, token, amount);
                    } else if (kind == PoolBalanceOpKind.DEPOSIT) {
                        return _depositPoolBalance(poolId, specialization, token, amount);
                    } else {
                        // PoolBalanceOpKind.UPDATE
                        return _updateManagedBalance(poolId, specialization, token, amount);
                    }
                }
                /**
                 * @dev Moves `amount` tokens from a Pool's 'cash' to 'managed' balance, and transfers them to the caller.
                 *
                 * Returns the 'cash' and 'managed' balance deltas as a result of this call, which will be complementary.
                 */
                function _withdrawPoolBalance(
                    bytes32 poolId,
                    PoolSpecialization specialization,
                    IERC20 token,
                    uint256 amount
                ) private returns (int256 cashDelta, int256 managedDelta) {
                    if (specialization == PoolSpecialization.TWO_TOKEN) {
                        _twoTokenPoolCashToManaged(poolId, token, amount);
                    } else if (specialization == PoolSpecialization.MINIMAL_SWAP_INFO) {
                        _minimalSwapInfoPoolCashToManaged(poolId, token, amount);
                    } else {
                        // PoolSpecialization.GENERAL
                        _generalPoolCashToManaged(poolId, token, amount);
                    }
                    if (amount > 0) {
                        token.safeTransfer(msg.sender, amount);
                    }
                    // Since 'cash' and 'managed' are stored as uint112, `amount` is guaranteed to also fit in 112 bits. It will
                    // therefore always fit in a 256 bit integer.
                    cashDelta = int256(-amount);
                    managedDelta = int256(amount);
                }
                /**
                 * @dev Moves `amount` tokens from a Pool's 'managed' to 'cash' balance, and transfers them from the caller.
                 *
                 * Returns the 'cash' and 'managed' balance deltas as a result of this call, which will be complementary.
                 */
                function _depositPoolBalance(
                    bytes32 poolId,
                    PoolSpecialization specialization,
                    IERC20 token,
                    uint256 amount
                ) private returns (int256 cashDelta, int256 managedDelta) {
                    if (specialization == PoolSpecialization.TWO_TOKEN) {
                        _twoTokenPoolManagedToCash(poolId, token, amount);
                    } else if (specialization == PoolSpecialization.MINIMAL_SWAP_INFO) {
                        _minimalSwapInfoPoolManagedToCash(poolId, token, amount);
                    } else {
                        // PoolSpecialization.GENERAL
                        _generalPoolManagedToCash(poolId, token, amount);
                    }
                    if (amount > 0) {
                        token.safeTransferFrom(msg.sender, address(this), amount);
                    }
                    // Since 'cash' and 'managed' are stored as uint112, `amount` is guaranteed to also fit in 112 bits. It will
                    // therefore always fit in a 256 bit integer.
                    cashDelta = int256(amount);
                    managedDelta = int256(-amount);
                }
                /**
                 * @dev Sets a Pool's 'managed' balance to `amount`.
                 *
                 * Returns the 'cash' and 'managed' balance deltas as a result of this call (the 'cash' delta will always be zero).
                 */
                function _updateManagedBalance(
                    bytes32 poolId,
                    PoolSpecialization specialization,
                    IERC20 token,
                    uint256 amount
                ) private returns (int256 cashDelta, int256 managedDelta) {
                    if (specialization == PoolSpecialization.TWO_TOKEN) {
                        managedDelta = _setTwoTokenPoolManagedBalance(poolId, token, amount);
                    } else if (specialization == PoolSpecialization.MINIMAL_SWAP_INFO) {
                        managedDelta = _setMinimalSwapInfoPoolManagedBalance(poolId, token, amount);
                    } else {
                        // PoolSpecialization.GENERAL
                        managedDelta = _setGeneralPoolManagedBalance(poolId, token, amount);
                    }
                    cashDelta = 0;
                }
                /**
                 * @dev Returns true if `token` is registered for `poolId`.
                 */
                function _isTokenRegistered(bytes32 poolId, IERC20 token) private view returns (bool) {
                    PoolSpecialization specialization = _getPoolSpecialization(poolId);
                    if (specialization == PoolSpecialization.TWO_TOKEN) {
                        return _isTwoTokenPoolTokenRegistered(poolId, token);
                    } else if (specialization == PoolSpecialization.MINIMAL_SWAP_INFO) {
                        return _isMinimalSwapInfoPoolTokenRegistered(poolId, token);
                    } else {
                        // PoolSpecialization.GENERAL
                        return _isGeneralPoolTokenRegistered(poolId, token);
                    }
                }
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            pragma experimental ABIEncoderV2;
            import "../lib/helpers/BalancerErrors.sol";
            import "../lib/openzeppelin/ReentrancyGuard.sol";
            import "./VaultAuthorization.sol";
            /**
             * @dev Maintains the Pool ID data structure, implements Pool ID creation and registration, and defines useful modifiers
             * and helper functions for ensuring correct behavior when working with Pools.
             */
            abstract contract PoolRegistry is ReentrancyGuard, VaultAuthorization {
                // Each pool is represented by their unique Pool ID. We use `bytes32` for them, for lack of a way to define new
                // types.
                mapping(bytes32 => bool) private _isPoolRegistered;
                // We keep an increasing nonce to make Pool IDs unique. It is interpreted as a `uint80`, but storing it as a
                // `uint256` results in reduced bytecode on reads and writes due to the lack of masking.
                uint256 private _nextPoolNonce;
                /**
                 * @dev Reverts unless `poolId` corresponds to a registered Pool.
                 */
                modifier withRegisteredPool(bytes32 poolId) {
                    _ensureRegisteredPool(poolId);
                    _;
                }
                /**
                 * @dev Reverts unless `poolId` corresponds to a registered Pool, and the caller is the Pool's contract.
                 */
                modifier onlyPool(bytes32 poolId) {
                    _ensurePoolIsSender(poolId);
                    _;
                }
                /**
                 * @dev Reverts unless `poolId` corresponds to a registered Pool.
                 */
                function _ensureRegisteredPool(bytes32 poolId) internal view {
                    _require(_isPoolRegistered[poolId], Errors.INVALID_POOL_ID);
                }
                /**
                 * @dev Reverts unless `poolId` corresponds to a registered Pool, and the caller is the Pool's contract.
                 */
                function _ensurePoolIsSender(bytes32 poolId) private view {
                    _ensureRegisteredPool(poolId);
                    _require(msg.sender == _getPoolAddress(poolId), Errors.CALLER_NOT_POOL);
                }
                function registerPool(PoolSpecialization specialization)
                    external
                    override
                    nonReentrant
                    whenNotPaused
                    returns (bytes32)
                {
                    // Each Pool is assigned a unique ID based on an incrementing nonce. This assumes there will never be more than
                    // 2**80 Pools, and the nonce will not overflow.
                    bytes32 poolId = _toPoolId(msg.sender, specialization, uint80(_nextPoolNonce));
                    _require(!_isPoolRegistered[poolId], Errors.INVALID_POOL_ID); // Should never happen as Pool IDs are unique.
                    _isPoolRegistered[poolId] = true;
                    _nextPoolNonce += 1;
                    // Note that msg.sender is the pool's contract
                    emit PoolRegistered(poolId, msg.sender, specialization);
                    return poolId;
                }
                function getPool(bytes32 poolId)
                    external
                    view
                    override
                    withRegisteredPool(poolId)
                    returns (address, PoolSpecialization)
                {
                    return (_getPoolAddress(poolId), _getPoolSpecialization(poolId));
                }
                /**
                 * @dev Creates a Pool ID.
                 *
                 * These are deterministically created by packing the Pool's contract address and its specialization setting into
                 * the ID. This saves gas by making this data easily retrievable from a Pool ID with no storage accesses.
                 *
                 * Since a single contract can register multiple Pools, a unique nonce must be provided to ensure Pool IDs are
                 * unique.
                 *
                 * Pool IDs have the following layout:
                 * | 20 bytes pool contract address | 2 bytes specialization setting | 10 bytes nonce |
                 * MSB                                                                              LSB
                 *
                 * 2 bytes for the specialization setting is a bit overkill: there only three of them, which means two bits would
                 * suffice. However, there's nothing else of interest to store in this extra space.
                 */
                function _toPoolId(
                    address pool,
                    PoolSpecialization specialization,
                    uint80 nonce
                ) internal pure returns (bytes32) {
                    bytes32 serialized;
                    serialized |= bytes32(uint256(nonce));
                    serialized |= bytes32(uint256(specialization)) << (10 * 8);
                    serialized |= bytes32(uint256(pool)) << (12 * 8);
                    return serialized;
                }
                /**
                 * @dev Returns the address of a Pool's contract.
                 *
                 * Due to how Pool IDs are created, this is done with no storage accesses and costs little gas.
                 */
                function _getPoolAddress(bytes32 poolId) internal pure returns (address) {
                    // 12 byte logical shift left to remove the nonce and specialization setting. We don't need to mask,
                    // since the logical shift already sets the upper bits to zero.
                    return address(uint256(poolId) >> (12 * 8));
                }
                /**
                 * @dev Returns the specialization setting of a Pool.
                 *
                 * Due to how Pool IDs are created, this is done with no storage accesses and costs little gas.
                 */
                function _getPoolSpecialization(bytes32 poolId) internal pure returns (PoolSpecialization specialization) {
                    // 10 byte logical shift left to remove the nonce, followed by a 2 byte mask to remove the address.
                    uint256 value = uint256(poolId >> (10 * 8)) & (2**(2 * 8) - 1);
                    // Casting a value into an enum results in a runtime check that reverts unless the value is within the enum's
                    // range. Passing an invalid Pool ID to this function would then result in an obscure revert with no reason
                    // string: we instead perform the check ourselves to help in error diagnosis.
                    // There are three Pool specialization settings: general, minimal swap info and two tokens, which correspond to
                    // values 0, 1 and 2.
                    _require(value < 3, Errors.INVALID_POOL_ID);
                    // Because we have checked that `value` is within the enum range, we can use assembly to skip the runtime check.
                    // solhint-disable-next-line no-inline-assembly
                    assembly {
                        specialization := value
                    }
                }
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            import "../../lib/helpers/BalancerErrors.sol";
            import "../../lib/openzeppelin/EnumerableMap.sol";
            import "../../lib/openzeppelin/IERC20.sol";
            import "./BalanceAllocation.sol";
            abstract contract GeneralPoolsBalance {
                using BalanceAllocation for bytes32;
                using EnumerableMap for EnumerableMap.IERC20ToBytes32Map;
                // Data for Pools with the General specialization setting
                //
                // These Pools use the IGeneralPool interface, which means the Vault must query the balance for *all* of their
                // tokens in every swap. If we kept a mapping of token to balance plus a set (array) of tokens, it'd be very gas
                // intensive to read all token addresses just to then do a lookup on the balance mapping.
                //
                // Instead, we use our customized EnumerableMap, which lets us read the N balances in N+1 storage accesses (one for
                // each token in the Pool), access the index of any 'token in' a single read (required for the IGeneralPool call),
                // and update an entry's value given its index.
                // Map of token -> balance pairs for each Pool with this specialization. Many functions rely on storage pointers to
                // a Pool's EnumerableMap to save gas when computing storage slots.
                mapping(bytes32 => EnumerableMap.IERC20ToBytes32Map) internal _generalPoolsBalances;
                /**
                 * @dev Registers a list of tokens in a General Pool.
                 *
                 * This function assumes `poolId` exists and corresponds to the General specialization setting.
                 *
                 * Requirements:
                 *
                 * - `tokens` must not be registered in the Pool
                 * - `tokens` must not contain duplicates
                 */
                function _registerGeneralPoolTokens(bytes32 poolId, IERC20[] memory tokens) internal {
                    EnumerableMap.IERC20ToBytes32Map storage poolBalances = _generalPoolsBalances[poolId];
                    for (uint256 i = 0; i < tokens.length; ++i) {
                        // EnumerableMaps require an explicit initial value when creating a key-value pair: we use zero, the same
                        // value that is found in uninitialized storage, which corresponds to an empty balance.
                        bool added = poolBalances.set(tokens[i], 0);
                        _require(added, Errors.TOKEN_ALREADY_REGISTERED);
                    }
                }
                /**
                 * @dev Deregisters a list of tokens in a General Pool.
                 *
                 * This function assumes `poolId` exists and corresponds to the General specialization setting.
                 *
                 * Requirements:
                 *
                 * - `tokens` must be registered in the Pool
                 * - `tokens` must have zero balance in the Vault
                 * - `tokens` must not contain duplicates
                 */
                function _deregisterGeneralPoolTokens(bytes32 poolId, IERC20[] memory tokens) internal {
                    EnumerableMap.IERC20ToBytes32Map storage poolBalances = _generalPoolsBalances[poolId];
                    for (uint256 i = 0; i < tokens.length; ++i) {
                        IERC20 token = tokens[i];
                        bytes32 currentBalance = _getGeneralPoolBalance(poolBalances, token);
                        _require(currentBalance.isZero(), Errors.NONZERO_TOKEN_BALANCE);
                        // We don't need to check remove's return value, since _getGeneralPoolBalance already checks that the token
                        // was registered.
                        poolBalances.remove(token);
                    }
                }
                /**
                 * @dev Sets the balances of a General Pool's tokens to `balances`.
                 *
                 * WARNING: this assumes `balances` has the same length and order as the Pool's tokens.
                 */
                function _setGeneralPoolBalances(bytes32 poolId, bytes32[] memory balances) internal {
                    EnumerableMap.IERC20ToBytes32Map storage poolBalances = _generalPoolsBalances[poolId];
                    for (uint256 i = 0; i < balances.length; ++i) {
                        // Since we assume all balances are properly ordered, we can simply use `unchecked_setAt` to avoid one less
                        // storage read per token.
                        poolBalances.unchecked_setAt(i, balances[i]);
                    }
                }
                /**
                 * @dev Transforms `amount` of `token`'s balance in a General Pool from cash into managed.
                 *
                 * This function assumes `poolId` exists, corresponds to the General specialization setting, and that `token` is
                 * registered for that Pool.
                 */
                function _generalPoolCashToManaged(
                    bytes32 poolId,
                    IERC20 token,
                    uint256 amount
                ) internal {
                    _updateGeneralPoolBalance(poolId, token, BalanceAllocation.cashToManaged, amount);
                }
                /**
                 * @dev Transforms `amount` of `token`'s balance in a General Pool from managed into cash.
                 *
                 * This function assumes `poolId` exists, corresponds to the General specialization setting, and that `token` is
                 * registered for that Pool.
                 */
                function _generalPoolManagedToCash(
                    bytes32 poolId,
                    IERC20 token,
                    uint256 amount
                ) internal {
                    _updateGeneralPoolBalance(poolId, token, BalanceAllocation.managedToCash, amount);
                }
                /**
                 * @dev Sets `token`'s managed balance in a General Pool to `amount`.
                 *
                 * This function assumes `poolId` exists, corresponds to the General specialization setting, and that `token` is
                 * registered for that Pool.
                 *
                 * Returns the managed balance delta as a result of this call.
                 */
                function _setGeneralPoolManagedBalance(
                    bytes32 poolId,
                    IERC20 token,
                    uint256 amount
                ) internal returns (int256) {
                    return _updateGeneralPoolBalance(poolId, token, BalanceAllocation.setManaged, amount);
                }
                /**
                 * @dev Sets `token`'s balance in a General Pool to the result of the `mutation` function when called with the
                 * current balance and `amount`.
                 *
                 * This function assumes `poolId` exists, corresponds to the General specialization setting, and that `token` is
                 * registered for that Pool.
                 *
                 * Returns the managed balance delta as a result of this call.
                 */
                function _updateGeneralPoolBalance(
                    bytes32 poolId,
                    IERC20 token,
                    function(bytes32, uint256) returns (bytes32) mutation,
                    uint256 amount
                ) private returns (int256) {
                    EnumerableMap.IERC20ToBytes32Map storage poolBalances = _generalPoolsBalances[poolId];
                    bytes32 currentBalance = _getGeneralPoolBalance(poolBalances, token);
                    bytes32 newBalance = mutation(currentBalance, amount);
                    poolBalances.set(token, newBalance);
                    return newBalance.managedDelta(currentBalance);
                }
                /**
                 * @dev Returns an array with all the tokens and balances in a General Pool. The order may change when tokens are
                 * registered or deregistered.
                 *
                 * This function assumes `poolId` exists and corresponds to the General specialization setting.
                 */
                function _getGeneralPoolTokens(bytes32 poolId)
                    internal
                    view
                    returns (IERC20[] memory tokens, bytes32[] memory balances)
                {
                    EnumerableMap.IERC20ToBytes32Map storage poolBalances = _generalPoolsBalances[poolId];
                    tokens = new IERC20[](poolBalances.length());
                    balances = new bytes32[](tokens.length);
                    for (uint256 i = 0; i < tokens.length; ++i) {
                        // Because the iteration is bounded by `tokens.length`, which matches the EnumerableMap's length, we can use
                        // `unchecked_at` as we know `i` is a valid token index, saving storage reads.
                        (tokens[i], balances[i]) = poolBalances.unchecked_at(i);
                    }
                }
                /**
                 * @dev Returns the balance of a token in a General Pool.
                 *
                 * This function assumes `poolId` exists and corresponds to the General specialization setting.
                 *
                 * Requirements:
                 *
                 * - `token` must be registered in the Pool
                 */
                function _getGeneralPoolBalance(bytes32 poolId, IERC20 token) internal view returns (bytes32) {
                    EnumerableMap.IERC20ToBytes32Map storage poolBalances = _generalPoolsBalances[poolId];
                    return _getGeneralPoolBalance(poolBalances, token);
                }
                /**
                 * @dev Same as `_getGeneralPoolBalance` but using a Pool's storage pointer, which saves gas in repeated reads and
                 * writes.
                 */
                function _getGeneralPoolBalance(EnumerableMap.IERC20ToBytes32Map storage poolBalances, IERC20 token)
                    private
                    view
                    returns (bytes32)
                {
                    return poolBalances.get(token, Errors.TOKEN_NOT_REGISTERED);
                }
                /**
                 * @dev Returns true if `token` is registered in a General Pool.
                 *
                 * This function assumes `poolId` exists and corresponds to the General specialization setting.
                 */
                function _isGeneralPoolTokenRegistered(bytes32 poolId, IERC20 token) internal view returns (bool) {
                    EnumerableMap.IERC20ToBytes32Map storage poolBalances = _generalPoolsBalances[poolId];
                    return poolBalances.contains(token);
                }
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            pragma experimental ABIEncoderV2;
            import "../../lib/helpers/BalancerErrors.sol";
            import "../../lib/openzeppelin/EnumerableSet.sol";
            import "../../lib/openzeppelin/IERC20.sol";
            import "./BalanceAllocation.sol";
            import "../PoolRegistry.sol";
            abstract contract MinimalSwapInfoPoolsBalance is PoolRegistry {
                using BalanceAllocation for bytes32;
                using EnumerableSet for EnumerableSet.AddressSet;
                // Data for Pools with the Minimal Swap Info specialization setting
                //
                // These Pools use the IMinimalSwapInfoPool interface, and so the Vault must read the balance of the two tokens
                // in the swap. The best solution is to use a mapping from token to balance, which lets us read or write any token's
                // balance in a single storage access.
                //
                // We also keep a set of registered tokens. Because tokens with non-zero balance are by definition registered, in
                // some balance getters we skip checking for token registration if a non-zero balance is found, saving gas by
                // performing a single read instead of two.
                mapping(bytes32 => mapping(IERC20 => bytes32)) internal _minimalSwapInfoPoolsBalances;
                mapping(bytes32 => EnumerableSet.AddressSet) internal _minimalSwapInfoPoolsTokens;
                /**
                 * @dev Registers a list of tokens in a Minimal Swap Info Pool.
                 *
                 * This function assumes `poolId` exists and corresponds to the Minimal Swap Info specialization setting.
                 *
                 * Requirements:
                 *
                 * - `tokens` must not be registered in the Pool
                 * - `tokens` must not contain duplicates
                 */
                function _registerMinimalSwapInfoPoolTokens(bytes32 poolId, IERC20[] memory tokens) internal {
                    EnumerableSet.AddressSet storage poolTokens = _minimalSwapInfoPoolsTokens[poolId];
                    for (uint256 i = 0; i < tokens.length; ++i) {
                        bool added = poolTokens.add(address(tokens[i]));
                        _require(added, Errors.TOKEN_ALREADY_REGISTERED);
                        // Note that we don't initialize the balance mapping: the default value of zero corresponds to an empty
                        // balance.
                    }
                }
                /**
                 * @dev Deregisters a list of tokens in a Minimal Swap Info Pool.
                 *
                 * This function assumes `poolId` exists and corresponds to the Minimal Swap Info specialization setting.
                 *
                 * Requirements:
                 *
                 * - `tokens` must be registered in the Pool
                 * - `tokens` must have zero balance in the Vault
                 * - `tokens` must not contain duplicates
                 */
                function _deregisterMinimalSwapInfoPoolTokens(bytes32 poolId, IERC20[] memory tokens) internal {
                    EnumerableSet.AddressSet storage poolTokens = _minimalSwapInfoPoolsTokens[poolId];
                    for (uint256 i = 0; i < tokens.length; ++i) {
                        IERC20 token = tokens[i];
                        _require(_minimalSwapInfoPoolsBalances[poolId][token].isZero(), Errors.NONZERO_TOKEN_BALANCE);
                        // For consistency with other Pool specialization settings, we explicitly reset the balance (which may have
                        // a non-zero last change block).
                        delete _minimalSwapInfoPoolsBalances[poolId][token];
                        bool removed = poolTokens.remove(address(token));
                        _require(removed, Errors.TOKEN_NOT_REGISTERED);
                    }
                }
                /**
                 * @dev Sets the balances of a Minimal Swap Info Pool's tokens to `balances`.
                 *
                 * WARNING: this assumes `balances` has the same length and order as the Pool's tokens.
                 */
                function _setMinimalSwapInfoPoolBalances(
                    bytes32 poolId,
                    IERC20[] memory tokens,
                    bytes32[] memory balances
                ) internal {
                    for (uint256 i = 0; i < tokens.length; ++i) {
                        _minimalSwapInfoPoolsBalances[poolId][tokens[i]] = balances[i];
                    }
                }
                /**
                 * @dev Transforms `amount` of `token`'s balance in a Minimal Swap Info Pool from cash into managed.
                 *
                 * This function assumes `poolId` exists, corresponds to the Minimal Swap Info specialization setting, and that
                 * `token` is registered for that Pool.
                 */
                function _minimalSwapInfoPoolCashToManaged(
                    bytes32 poolId,
                    IERC20 token,
                    uint256 amount
                ) internal {
                    _updateMinimalSwapInfoPoolBalance(poolId, token, BalanceAllocation.cashToManaged, amount);
                }
                /**
                 * @dev Transforms `amount` of `token`'s balance in a Minimal Swap Info Pool from managed into cash.
                 *
                 * This function assumes `poolId` exists, corresponds to the Minimal Swap Info specialization setting, and that
                 * `token` is registered for that Pool.
                 */
                function _minimalSwapInfoPoolManagedToCash(
                    bytes32 poolId,
                    IERC20 token,
                    uint256 amount
                ) internal {
                    _updateMinimalSwapInfoPoolBalance(poolId, token, BalanceAllocation.managedToCash, amount);
                }
                /**
                 * @dev Sets `token`'s managed balance in a Minimal Swap Info Pool to `amount`.
                 *
                 * This function assumes `poolId` exists, corresponds to the Minimal Swap Info specialization setting, and that
                 * `token` is registered for that Pool.
                 *
                 * Returns the managed balance delta as a result of this call.
                 */
                function _setMinimalSwapInfoPoolManagedBalance(
                    bytes32 poolId,
                    IERC20 token,
                    uint256 amount
                ) internal returns (int256) {
                    return _updateMinimalSwapInfoPoolBalance(poolId, token, BalanceAllocation.setManaged, amount);
                }
                /**
                 * @dev Sets `token`'s balance in a Minimal Swap Info Pool to the result of the `mutation` function when called with
                 * the current balance and `amount`.
                 *
                 * This function assumes `poolId` exists, corresponds to the Minimal Swap Info specialization setting, and that
                 * `token` is registered for that Pool.
                 *
                 * Returns the managed balance delta as a result of this call.
                 */
                function _updateMinimalSwapInfoPoolBalance(
                    bytes32 poolId,
                    IERC20 token,
                    function(bytes32, uint256) returns (bytes32) mutation,
                    uint256 amount
                ) internal returns (int256) {
                    bytes32 currentBalance = _getMinimalSwapInfoPoolBalance(poolId, token);
                    bytes32 newBalance = mutation(currentBalance, amount);
                    _minimalSwapInfoPoolsBalances[poolId][token] = newBalance;
                    return newBalance.managedDelta(currentBalance);
                }
                /**
                 * @dev Returns an array with all the tokens and balances in a Minimal Swap Info Pool. The order may change when
                 * tokens are registered or deregistered.
                 *
                 * This function assumes `poolId` exists and corresponds to the Minimal Swap Info specialization setting.
                 */
                function _getMinimalSwapInfoPoolTokens(bytes32 poolId)
                    internal
                    view
                    returns (IERC20[] memory tokens, bytes32[] memory balances)
                {
                    EnumerableSet.AddressSet storage poolTokens = _minimalSwapInfoPoolsTokens[poolId];
                    tokens = new IERC20[](poolTokens.length());
                    balances = new bytes32[](tokens.length);
                    for (uint256 i = 0; i < tokens.length; ++i) {
                        // Because the iteration is bounded by `tokens.length`, which matches the EnumerableSet's length, we can use
                        // `unchecked_at` as we know `i` is a valid token index, saving storage reads.
                        IERC20 token = IERC20(poolTokens.unchecked_at(i));
                        tokens[i] = token;
                        balances[i] = _minimalSwapInfoPoolsBalances[poolId][token];
                    }
                }
                /**
                 * @dev Returns the balance of a token in a Minimal Swap Info Pool.
                 *
                 * Requirements:
                 *
                 * - `poolId` must be a Minimal Swap Info Pool
                 * - `token` must be registered in the Pool
                 */
                function _getMinimalSwapInfoPoolBalance(bytes32 poolId, IERC20 token) internal view returns (bytes32) {
                    bytes32 balance = _minimalSwapInfoPoolsBalances[poolId][token];
                    // A non-zero balance guarantees that the token is registered. If zero, we manually check if the token is
                    // registered in the Pool. Token registration implies that the Pool is registered as well, which lets us save
                    // gas by not performing the check.
                    bool tokenRegistered = balance.isNotZero() || _minimalSwapInfoPoolsTokens[poolId].contains(address(token));
                    if (!tokenRegistered) {
                        // The token might not be registered because the Pool itself is not registered. We check this to provide a
                        // more accurate revert reason.
                        _ensureRegisteredPool(poolId);
                        _revert(Errors.TOKEN_NOT_REGISTERED);
                    }
                    return balance;
                }
                /**
                 * @dev Returns true if `token` is registered in a Minimal Swap Info Pool.
                 *
                 * This function assumes `poolId` exists and corresponds to the Minimal Swap Info specialization setting.
                 */
                function _isMinimalSwapInfoPoolTokenRegistered(bytes32 poolId, IERC20 token) internal view returns (bool) {
                    EnumerableSet.AddressSet storage poolTokens = _minimalSwapInfoPoolsTokens[poolId];
                    return poolTokens.contains(address(token));
                }
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            pragma experimental ABIEncoderV2;
            import "../../lib/helpers/BalancerErrors.sol";
            import "../../lib/openzeppelin/IERC20.sol";
            import "./BalanceAllocation.sol";
            import "../PoolRegistry.sol";
            abstract contract TwoTokenPoolsBalance is PoolRegistry {
                using BalanceAllocation for bytes32;
                // Data for Pools with the Two Token specialization setting
                //
                // These are similar to the Minimal Swap Info Pool case (because the Pool only has two tokens, and therefore there
                // are only two balances to read), but there's a key difference in how data is stored. Keeping a set makes little
                // sense, as it will only ever hold two tokens, so we can just store those two directly.
                //
                // The gas savings associated with using these Pools come from how token balances are stored: cash amounts for token
                // A and token B are packed together, as are managed amounts. Because only cash changes in a swap, there's no need
                // to write to this second storage slot. A single last change block number for both tokens is stored with the packed
                // cash fields.
                struct TwoTokenPoolBalances {
                    bytes32 sharedCash;
                    bytes32 sharedManaged;
                }
                // We could just keep a mapping from Pool ID to TwoTokenSharedBalances, but there's an issue: we wouldn't know to
                // which tokens those balances correspond. This would mean having to also check which are registered with the Pool.
                //
                // What we do instead to save those storage reads is keep a nested mapping from the token pair hash to the balances
                // struct. The Pool only has two tokens, so only a single entry of this mapping is set (the one that corresponds to
                // that pair's hash).
                //
                // This has the trade-off of making Vault code that interacts with these Pools cumbersome: both balances must be
                // accessed at the same time by using both token addresses, and some logic is needed to determine how the pair hash
                // is computed. We do this by sorting the tokens, calling the token with the lowest numerical address value token A,
                // and the other one token B. In functions where the token arguments could be either A or B, we use X and Y instead.
                //
                // If users query a token pair containing an unregistered token, the Pool will generate a hash for a mapping entry
                // that was not set, and return zero balances. Non-zero balances are only possible if both tokens in the pair
                // are registered with the Pool, which means we don't have to check the TwoTokenPoolTokens struct, and can save
                // storage reads.
                struct TwoTokenPoolTokens {
                    IERC20 tokenA;
                    IERC20 tokenB;
                    mapping(bytes32 => TwoTokenPoolBalances) balances;
                }
                mapping(bytes32 => TwoTokenPoolTokens) private _twoTokenPoolTokens;
                /**
                 * @dev Registers tokens in a Two Token Pool.
                 *
                 * This function assumes `poolId` exists and corresponds to the Two Token specialization setting.
                 *
                 * Requirements:
                 *
                 * - `tokenX` and `tokenY` must not be the same
                 * - The tokens must be ordered: tokenX < tokenY
                 */
                function _registerTwoTokenPoolTokens(
                    bytes32 poolId,
                    IERC20 tokenX,
                    IERC20 tokenY
                ) internal {
                    // Not technically true since we didn't register yet, but this is consistent with the error messages of other
                    // specialization settings.
                    _require(tokenX != tokenY, Errors.TOKEN_ALREADY_REGISTERED);
                    _require(tokenX < tokenY, Errors.UNSORTED_TOKENS);
                    // A Two Token Pool with no registered tokens is identified by having zero addresses for tokens A and B.
                    TwoTokenPoolTokens storage poolTokens = _twoTokenPoolTokens[poolId];
                    _require(poolTokens.tokenA == IERC20(0) && poolTokens.tokenB == IERC20(0), Errors.TOKENS_ALREADY_SET);
                    // Since tokenX < tokenY, tokenX is A and tokenY is B
                    poolTokens.tokenA = tokenX;
                    poolTokens.tokenB = tokenY;
                    // Note that we don't initialize the balance mapping: the default value of zero corresponds to an empty
                    // balance.
                }
                /**
                 * @dev Deregisters tokens in a Two Token Pool.
                 *
                 * This function assumes `poolId` exists and corresponds to the Two Token specialization setting.
                 *
                 * Requirements:
                 *
                 * - `tokenX` and `tokenY` must be registered in the Pool
                 * - both tokens must have zero balance in the Vault
                 */
                function _deregisterTwoTokenPoolTokens(
                    bytes32 poolId,
                    IERC20 tokenX,
                    IERC20 tokenY
                ) internal {
                    (
                        bytes32 balanceA,
                        bytes32 balanceB,
                        TwoTokenPoolBalances storage poolBalances
                    ) = _getTwoTokenPoolSharedBalances(poolId, tokenX, tokenY);
                    _require(balanceA.isZero() && balanceB.isZero(), Errors.NONZERO_TOKEN_BALANCE);
                    delete _twoTokenPoolTokens[poolId];
                    // For consistency with other Pool specialization settings, we explicitly reset the packed cash field (which may
                    // have a non-zero last change block).
                    delete poolBalances.sharedCash;
                }
                /**
                 * @dev Sets the cash balances of a Two Token Pool's tokens.
                 *
                 * WARNING: this assumes `tokenA` and `tokenB` are the Pool's two registered tokens, and are in the correct order.
                 */
                function _setTwoTokenPoolCashBalances(
                    bytes32 poolId,
                    IERC20 tokenA,
                    bytes32 balanceA,
                    IERC20 tokenB,
                    bytes32 balanceB
                ) internal {
                    bytes32 pairHash = _getTwoTokenPairHash(tokenA, tokenB);
                    TwoTokenPoolBalances storage poolBalances = _twoTokenPoolTokens[poolId].balances[pairHash];
                    poolBalances.sharedCash = BalanceAllocation.toSharedCash(balanceA, balanceB);
                }
                /**
                 * @dev Transforms `amount` of `token`'s balance in a Two Token Pool from cash into managed.
                 *
                 * This function assumes `poolId` exists, corresponds to the Two Token specialization setting, and that `token` is
                 * registered for that Pool.
                 */
                function _twoTokenPoolCashToManaged(
                    bytes32 poolId,
                    IERC20 token,
                    uint256 amount
                ) internal {
                    _updateTwoTokenPoolSharedBalance(poolId, token, BalanceAllocation.cashToManaged, amount);
                }
                /**
                 * @dev Transforms `amount` of `token`'s balance in a Two Token Pool from managed into cash.
                 *
                 * This function assumes `poolId` exists, corresponds to the Two Token specialization setting, and that `token` is
                 * registered for that Pool.
                 */
                function _twoTokenPoolManagedToCash(
                    bytes32 poolId,
                    IERC20 token,
                    uint256 amount
                ) internal {
                    _updateTwoTokenPoolSharedBalance(poolId, token, BalanceAllocation.managedToCash, amount);
                }
                /**
                 * @dev Sets `token`'s managed balance in a Two Token Pool to `amount`.
                 *
                 * This function assumes `poolId` exists, corresponds to the Two Token specialization setting, and that `token` is
                 * registered for that Pool.
                 *
                 * Returns the managed balance delta as a result of this call.
                 */
                function _setTwoTokenPoolManagedBalance(
                    bytes32 poolId,
                    IERC20 token,
                    uint256 amount
                ) internal returns (int256) {
                    return _updateTwoTokenPoolSharedBalance(poolId, token, BalanceAllocation.setManaged, amount);
                }
                /**
                 * @dev Sets `token`'s balance in a Two Token Pool to the result of the `mutation` function when called with
                 * the current balance and `amount`.
                 *
                 * This function assumes `poolId` exists, corresponds to the Two Token specialization setting, and that `token` is
                 * registered for that Pool.
                 *
                 * Returns the managed balance delta as a result of this call.
                 */
                function _updateTwoTokenPoolSharedBalance(
                    bytes32 poolId,
                    IERC20 token,
                    function(bytes32, uint256) returns (bytes32) mutation,
                    uint256 amount
                ) private returns (int256) {
                    (
                        TwoTokenPoolBalances storage balances,
                        IERC20 tokenA,
                        bytes32 balanceA,
                        ,
                        bytes32 balanceB
                    ) = _getTwoTokenPoolBalances(poolId);
                    int256 delta;
                    if (token == tokenA) {
                        bytes32 newBalance = mutation(balanceA, amount);
                        delta = newBalance.managedDelta(balanceA);
                        balanceA = newBalance;
                    } else {
                        // token == tokenB
                        bytes32 newBalance = mutation(balanceB, amount);
                        delta = newBalance.managedDelta(balanceB);
                        balanceB = newBalance;
                    }
                    balances.sharedCash = BalanceAllocation.toSharedCash(balanceA, balanceB);
                    balances.sharedManaged = BalanceAllocation.toSharedManaged(balanceA, balanceB);
                    return delta;
                }
                /*
                 * @dev Returns an array with all the tokens and balances in a Two Token Pool. The order may change when
                 * tokens are registered or deregistered.
                 *
                 * This function assumes `poolId` exists and corresponds to the Two Token specialization setting.
                 */
                function _getTwoTokenPoolTokens(bytes32 poolId)
                    internal
                    view
                    returns (IERC20[] memory tokens, bytes32[] memory balances)
                {
                    (, IERC20 tokenA, bytes32 balanceA, IERC20 tokenB, bytes32 balanceB) = _getTwoTokenPoolBalances(poolId);
                    // Both tokens will either be zero (if unregistered) or non-zero (if registered), but we keep the full check for
                    // clarity.
                    if (tokenA == IERC20(0) || tokenB == IERC20(0)) {
                        return (new IERC20[](0), new bytes32[](0));
                    }
                    // Note that functions relying on this getter expect tokens to be properly ordered, so we use the (A, B)
                    // ordering.
                    tokens = new IERC20[](2);
                    tokens[0] = tokenA;
                    tokens[1] = tokenB;
                    balances = new bytes32[](2);
                    balances[0] = balanceA;
                    balances[1] = balanceB;
                }
                /**
                 * @dev Same as `_getTwoTokenPoolTokens`, except it returns the two tokens and balances directly instead of using
                 * an array, as well as a storage pointer to the `TwoTokenPoolBalances` struct, which can be used to update it
                 * without having to recompute the pair hash and storage slot.
                 */
                function _getTwoTokenPoolBalances(bytes32 poolId)
                    private
                    view
                    returns (
                        TwoTokenPoolBalances storage poolBalances,
                        IERC20 tokenA,
                        bytes32 balanceA,
                        IERC20 tokenB,
                        bytes32 balanceB
                    )
                {
                    TwoTokenPoolTokens storage poolTokens = _twoTokenPoolTokens[poolId];
                    tokenA = poolTokens.tokenA;
                    tokenB = poolTokens.tokenB;
                    bytes32 pairHash = _getTwoTokenPairHash(tokenA, tokenB);
                    poolBalances = poolTokens.balances[pairHash];
                    bytes32 sharedCash = poolBalances.sharedCash;
                    bytes32 sharedManaged = poolBalances.sharedManaged;
                    balanceA = BalanceAllocation.fromSharedToBalanceA(sharedCash, sharedManaged);
                    balanceB = BalanceAllocation.fromSharedToBalanceB(sharedCash, sharedManaged);
                }
                /**
                 * @dev Returns the balance of a token in a Two Token Pool.
                 *
                 * This function assumes `poolId` exists and corresponds to the General specialization setting.
                 *
                 * This function is convenient but not particularly gas efficient, and should be avoided during gas-sensitive
                 * operations, such as swaps. For those, _getTwoTokenPoolSharedBalances provides a more flexible interface.
                 *
                 * Requirements:
                 *
                 * - `token` must be registered in the Pool
                 */
                function _getTwoTokenPoolBalance(bytes32 poolId, IERC20 token) internal view returns (bytes32) {
                    // We can't just read the balance of token, because we need to know the full pair in order to compute the pair
                    // hash and access the balance mapping. We therefore rely on `_getTwoTokenPoolBalances`.
                    (, IERC20 tokenA, bytes32 balanceA, IERC20 tokenB, bytes32 balanceB) = _getTwoTokenPoolBalances(poolId);
                    if (token == tokenA) {
                        return balanceA;
                    } else if (token == tokenB) {
                        return balanceB;
                    } else {
                        _revert(Errors.TOKEN_NOT_REGISTERED);
                    }
                }
                /**
                 * @dev Returns the balance of the two tokens in a Two Token Pool.
                 *
                 * The returned balances are those of token A and token B, where token A is the lowest of token X and token Y, and
                 * token B the other.
                 *
                 * This function also returns a storage pointer to the TwoTokenPoolBalances struct associated with the token pair,
                 * which can be used to update it without having to recompute the pair hash and storage slot.
                 *
                 * Requirements:
                 *
                 * - `poolId` must be a Minimal Swap Info Pool
                 * - `tokenX` and `tokenY` must be registered in the Pool
                 */
                function _getTwoTokenPoolSharedBalances(
                    bytes32 poolId,
                    IERC20 tokenX,
                    IERC20 tokenY
                )
                    internal
                    view
                    returns (
                        bytes32 balanceA,
                        bytes32 balanceB,
                        TwoTokenPoolBalances storage poolBalances
                    )
                {
                    (IERC20 tokenA, IERC20 tokenB) = _sortTwoTokens(tokenX, tokenY);
                    bytes32 pairHash = _getTwoTokenPairHash(tokenA, tokenB);
                    poolBalances = _twoTokenPoolTokens[poolId].balances[pairHash];
                    // Because we're reading balances using the pair hash, if either token X or token Y is not registered then
                    // *both* balance entries will be zero.
                    bytes32 sharedCash = poolBalances.sharedCash;
                    bytes32 sharedManaged = poolBalances.sharedManaged;
                    // A non-zero balance guarantees that both tokens are registered. If zero, we manually check whether each
                    // token is registered in the Pool. Token registration implies that the Pool is registered as well, which
                    // lets us save gas by not performing the check.
                    bool tokensRegistered = sharedCash.isNotZero() ||
                        sharedManaged.isNotZero() ||
                        (_isTwoTokenPoolTokenRegistered(poolId, tokenA) && _isTwoTokenPoolTokenRegistered(poolId, tokenB));
                    if (!tokensRegistered) {
                        // The tokens might not be registered because the Pool itself is not registered. We check this to provide a
                        // more accurate revert reason.
                        _ensureRegisteredPool(poolId);
                        _revert(Errors.TOKEN_NOT_REGISTERED);
                    }
                    balanceA = BalanceAllocation.fromSharedToBalanceA(sharedCash, sharedManaged);
                    balanceB = BalanceAllocation.fromSharedToBalanceB(sharedCash, sharedManaged);
                }
                /**
                 * @dev Returns true if `token` is registered in a Two Token Pool.
                 *
                 * This function assumes `poolId` exists and corresponds to the Two Token specialization setting.
                 */
                function _isTwoTokenPoolTokenRegistered(bytes32 poolId, IERC20 token) internal view returns (bool) {
                    TwoTokenPoolTokens storage poolTokens = _twoTokenPoolTokens[poolId];
                    // The zero address can never be a registered token.
                    return (token == poolTokens.tokenA || token == poolTokens.tokenB) && token != IERC20(0);
                }
                /**
                 * @dev Returns the hash associated with a given token pair.
                 */
                function _getTwoTokenPairHash(IERC20 tokenA, IERC20 tokenB) private pure returns (bytes32) {
                    return keccak256(abi.encodePacked(tokenA, tokenB));
                }
                /**
                 * @dev Sorts two tokens in ascending order, returning them as a (tokenA, tokenB) tuple.
                 */
                function _sortTwoTokens(IERC20 tokenX, IERC20 tokenY) private pure returns (IERC20, IERC20) {
                    return tokenX < tokenY ? (tokenX, tokenY) : (tokenY, tokenX);
                }
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            pragma experimental ABIEncoderV2;
            import "../lib/math/Math.sol";
            import "../lib/helpers/BalancerErrors.sol";
            import "../lib/openzeppelin/IERC20.sol";
            import "../lib/helpers/AssetHelpers.sol";
            import "../lib/openzeppelin/SafeERC20.sol";
            import "../lib/openzeppelin/Address.sol";
            import "./interfaces/IWETH.sol";
            import "./interfaces/IAsset.sol";
            import "./interfaces/IVault.sol";
            abstract contract AssetTransfersHandler is AssetHelpers {
                using SafeERC20 for IERC20;
                using Address for address payable;
                /**
                 * @dev Receives `amount` of `asset` from `sender`. If `fromInternalBalance` is true, it first withdraws as much
                 * as possible from Internal Balance, then transfers any remaining amount.
                 *
                 * If `asset` is ETH, `fromInternalBalance` must be false (as ETH cannot be held as internal balance), and the funds
                 * will be wrapped into WETH.
                 *
                 * WARNING: this function does not check that the contract caller has actually supplied any ETH - it is up to the
                 * caller of this function to check that this is true to prevent the Vault from using its own ETH (though the Vault
                 * typically doesn't hold any).
                 */
                function _receiveAsset(
                    IAsset asset,
                    uint256 amount,
                    address sender,
                    bool fromInternalBalance
                ) internal {
                    if (amount == 0) {
                        return;
                    }
                    if (_isETH(asset)) {
                        _require(!fromInternalBalance, Errors.INVALID_ETH_INTERNAL_BALANCE);
                        // The ETH amount to receive is deposited into the WETH contract, which will in turn mint WETH for
                        // the Vault at a 1:1 ratio.
                        // A check for this condition is also introduced by the compiler, but this one provides a revert reason.
                        // Note we're checking for the Vault's total balance, *not* ETH sent in this transaction.
                        _require(address(this).balance >= amount, Errors.INSUFFICIENT_ETH);
                        _WETH().deposit{ value: amount }();
                    } else {
                        IERC20 token = _asIERC20(asset);
                        if (fromInternalBalance) {
                            // We take as many tokens from Internal Balance as possible: any remaining amounts will be transferred.
                            uint256 deductedBalance = _decreaseInternalBalance(sender, token, amount, true);
                            // Because `deductedBalance` will be always the lesser of the current internal balance
                            // and the amount to decrease, it is safe to perform unchecked arithmetic.
                            amount -= deductedBalance;
                        }
                        if (amount > 0) {
                            token.safeTransferFrom(sender, address(this), amount);
                        }
                    }
                }
                /**
                 * @dev Sends `amount` of `asset` to `recipient`. If `toInternalBalance` is true, the asset is deposited as Internal
                 * Balance instead of being transferred.
                 *
                 * If `asset` is ETH, `toInternalBalance` must be false (as ETH cannot be held as internal balance), and the funds
                 * are instead sent directly after unwrapping WETH.
                 */
                function _sendAsset(
                    IAsset asset,
                    uint256 amount,
                    address payable recipient,
                    bool toInternalBalance
                ) internal {
                    if (amount == 0) {
                        return;
                    }
                    if (_isETH(asset)) {
                        // Sending ETH is not as involved as receiving it: the only special behavior is it cannot be
                        // deposited to Internal Balance.
                        _require(!toInternalBalance, Errors.INVALID_ETH_INTERNAL_BALANCE);
                        // First, the Vault withdraws deposited ETH from the WETH contract, by burning the same amount of WETH
                        // from the Vault. This receipt will be handled by the Vault's `receive`.
                        _WETH().withdraw(amount);
                        // Then, the withdrawn ETH is sent to the recipient.
                        recipient.sendValue(amount);
                    } else {
                        IERC20 token = _asIERC20(asset);
                        if (toInternalBalance) {
                            _increaseInternalBalance(recipient, token, amount);
                        } else {
                            token.safeTransfer(recipient, amount);
                        }
                    }
                }
                /**
                 * @dev Returns excess ETH back to the contract caller, assuming `amountUsed` has been spent. Reverts
                 * if the caller sent less ETH than `amountUsed`.
                 *
                 * Because the caller might not know exactly how much ETH a Vault action will require, they may send extra.
                 * Note that this excess value is returned *to the contract caller* (msg.sender). If caller and e.g. swap sender are
                 * not the same (because the caller is a relayer for the sender), then it is up to the caller to manage this
                 * returned ETH.
                 */
                function _handleRemainingEth(uint256 amountUsed) internal {
                    _require(msg.value >= amountUsed, Errors.INSUFFICIENT_ETH);
                    uint256 excess = msg.value - amountUsed;
                    if (excess > 0) {
                        msg.sender.sendValue(excess);
                    }
                }
                /**
                 * @dev Enables the Vault to receive ETH. This is required for it to be able to unwrap WETH, which sends ETH to the
                 * caller.
                 *
                 * Any ETH sent to the Vault outside of the WETH unwrapping mechanism would be forever locked inside the Vault, so
                 * we prevent that from happening. Other mechanisms used to send ETH to the Vault (such as being the recipient of an
                 * ETH swap, Pool exit or withdrawal, contract self-destruction, or receiving the block mining reward) will result
                 * in locked funds, but are not otherwise a security or soundness issue. This check only exists as an attempt to
                 * prevent user error.
                 */
                receive() external payable {
                    _require(msg.sender == address(_WETH()), Errors.ETH_TRANSFER);
                }
                // This contract uses virtual internal functions instead of inheriting from the modules that implement them (in
                // this case UserBalance) in order to decouple it from the rest of the system and enable standalone testing by
                // implementing these with mocks.
                function _increaseInternalBalance(
                    address account,
                    IERC20 token,
                    uint256 amount
                ) internal virtual;
                function _decreaseInternalBalance(
                    address account,
                    IERC20 token,
                    uint256 amount,
                    bool capped
                ) internal virtual returns (uint256);
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            import "../openzeppelin/IERC20.sol";
            import "../../vault/interfaces/IAsset.sol";
            import "../../vault/interfaces/IWETH.sol";
            abstract contract AssetHelpers {
                // solhint-disable-next-line var-name-mixedcase
                IWETH private immutable _weth;
                // Sentinel value used to indicate WETH with wrapping/unwrapping semantics. The zero address is a good choice for
                // multiple reasons: it is cheap to pass as a calldata argument, it is a known invalid token and non-contract, and
                // it is an address Pools cannot register as a token.
                address private constant _ETH = address(0);
                constructor(IWETH weth) {
                    _weth = weth;
                }
                // solhint-disable-next-line func-name-mixedcase
                function _WETH() internal view returns (IWETH) {
                    return _weth;
                }
                /**
                 * @dev Returns true if `asset` is the sentinel value that represents ETH.
                 */
                function _isETH(IAsset asset) internal pure returns (bool) {
                    return address(asset) == _ETH;
                }
                /**
                 * @dev Translates `asset` into an equivalent IERC20 token address. If `asset` represents ETH, it will be translated
                 * to the WETH contract.
                 */
                function _translateToIERC20(IAsset asset) internal view returns (IERC20) {
                    return _isETH(asset) ? _WETH() : _asIERC20(asset);
                }
                /**
                 * @dev Same as `_translateToIERC20(IAsset)`, but for an entire array.
                 */
                function _translateToIERC20(IAsset[] memory assets) internal view returns (IERC20[] memory) {
                    IERC20[] memory tokens = new IERC20[](assets.length);
                    for (uint256 i = 0; i < assets.length; ++i) {
                        tokens[i] = _translateToIERC20(assets[i]);
                    }
                    return tokens;
                }
                /**
                 * @dev Interprets `asset` as an IERC20 token. This function should only be called on `asset` if `_isETH` previously
                 * returned false for it, that is, if `asset` is guaranteed not to be the ETH sentinel value.
                 */
                function _asIERC20(IAsset asset) internal pure returns (IERC20) {
                    return IERC20(address(asset));
                }
            }
            // SPDX-License-Identifier: MIT
            pragma solidity ^0.7.0;
            import "../helpers/BalancerErrors.sol";
            /**
             * @dev Collection of functions related to the address type
             */
            library Address {
                /**
                 * @dev Returns true if `account` is a contract.
                 *
                 * [IMPORTANT]
                 * ====
                 * It is unsafe to assume that an address for which this function returns
                 * false is an externally-owned account (EOA) and not a contract.
                 *
                 * Among others, `isContract` will return false for the following
                 * types of addresses:
                 *
                 *  - an externally-owned account
                 *  - a contract in construction
                 *  - an address where a contract will be created
                 *  - an address where a contract lived, but was destroyed
                 * ====
                 */
                function isContract(address account) internal view returns (bool) {
                    // This method relies on extcodesize, which returns 0 for contracts in
                    // construction, since the code is only stored at the end of the
                    // constructor execution.
                    uint256 size;
                    // solhint-disable-next-line no-inline-assembly
                    assembly {
                        size := extcodesize(account)
                    }
                    return size > 0;
                }
                /**
                 * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
                 * `recipient`, forwarding all available gas and reverting on errors.
                 *
                 * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
                 * of certain opcodes, possibly making contracts go over the 2300 gas limit
                 * imposed by `transfer`, making them unable to receive funds via
                 * `transfer`. {sendValue} removes this limitation.
                 *
                 * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
                 *
                 * IMPORTANT: because control is transferred to `recipient`, care must be
                 * taken to not create reentrancy vulnerabilities. Consider using
                 * {ReentrancyGuard} or the
                 * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
                 */
                function sendValue(address payable recipient, uint256 amount) internal {
                    _require(address(this).balance >= amount, Errors.ADDRESS_INSUFFICIENT_BALANCE);
                    // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
                    (bool success, ) = recipient.call{ value: amount }("");
                    _require(success, Errors.ADDRESS_CANNOT_SEND_VALUE);
                }
            }
            

            File 4 of 5: WETH9
            // Copyright (C) 2015, 2016, 2017 Dapphub
            
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            
            pragma solidity ^0.4.18;
            
            contract WETH9 {
                string public name     = "Wrapped Ether";
                string public symbol   = "WETH";
                uint8  public decimals = 18;
            
                event  Approval(address indexed src, address indexed guy, uint wad);
                event  Transfer(address indexed src, address indexed dst, uint wad);
                event  Deposit(address indexed dst, uint wad);
                event  Withdrawal(address indexed src, uint wad);
            
                mapping (address => uint)                       public  balanceOf;
                mapping (address => mapping (address => uint))  public  allowance;
            
                function() public payable {
                    deposit();
                }
                function deposit() public payable {
                    balanceOf[msg.sender] += msg.value;
                    Deposit(msg.sender, msg.value);
                }
                function withdraw(uint wad) public {
                    require(balanceOf[msg.sender] >= wad);
                    balanceOf[msg.sender] -= wad;
                    msg.sender.transfer(wad);
                    Withdrawal(msg.sender, wad);
                }
            
                function totalSupply() public view returns (uint) {
                    return this.balance;
                }
            
                function approve(address guy, uint wad) public returns (bool) {
                    allowance[msg.sender][guy] = wad;
                    Approval(msg.sender, guy, wad);
                    return true;
                }
            
                function transfer(address dst, uint wad) public returns (bool) {
                    return transferFrom(msg.sender, dst, wad);
                }
            
                function transferFrom(address src, address dst, uint wad)
                    public
                    returns (bool)
                {
                    require(balanceOf[src] >= wad);
            
                    if (src != msg.sender && allowance[src][msg.sender] != uint(-1)) {
                        require(allowance[src][msg.sender] >= wad);
                        allowance[src][msg.sender] -= wad;
                    }
            
                    balanceOf[src] -= wad;
                    balanceOf[dst] += wad;
            
                    Transfer(src, dst, wad);
            
                    return true;
                }
            }
            
            
            /*
                                GNU GENERAL PUBLIC LICENSE
                                   Version 3, 29 June 2007
            
             Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
             Everyone is permitted to copy and distribute verbatim copies
             of this license document, but changing it is not allowed.
            
                                        Preamble
            
              The GNU General Public License is a free, copyleft license for
            software and other kinds of works.
            
              The licenses for most software and other practical works are designed
            to take away your freedom to share and change the works.  By contrast,
            the GNU General Public License is intended to guarantee your freedom to
            share and change all versions of a program--to make sure it remains free
            software for all its users.  We, the Free Software Foundation, use the
            GNU General Public License for most of our software; it applies also to
            any other work released this way by its authors.  You can apply it to
            your programs, too.
            
              When we speak of free software, we are referring to freedom, not
            price.  Our General Public Licenses are designed to make sure that you
            have the freedom to distribute copies of free software (and charge for
            them if you wish), that you receive source code or can get it if you
            want it, that you can change the software or use pieces of it in new
            free programs, and that you know you can do these things.
            
              To protect your rights, we need to prevent others from denying you
            these rights or asking you to surrender the rights.  Therefore, you have
            certain responsibilities if you distribute copies of the software, or if
            you modify it: responsibilities to respect the freedom of others.
            
              For example, if you distribute copies of such a program, whether
            gratis or for a fee, you must pass on to the recipients the same
            freedoms that you received.  You must make sure that they, too, receive
            or can get the source code.  And you must show them these terms so they
            know their rights.
            
              Developers that use the GNU GPL protect your rights with two steps:
            (1) assert copyright on the software, and (2) offer you this License
            giving you legal permission to copy, distribute and/or modify it.
            
              For the developers' and authors' protection, the GPL clearly explains
            that there is no warranty for this free software.  For both users' and
            authors' sake, the GPL requires that modified versions be marked as
            changed, so that their problems will not be attributed erroneously to
            authors of previous versions.
            
              Some devices are designed to deny users access to install or run
            modified versions of the software inside them, although the manufacturer
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            have designed this version of the GPL to prohibit the practice for those
            products.  If such problems arise substantially in other domains, we
            stand ready to extend this provision to those domains in future versions
            of the GPL, as needed to protect the freedom of users.
            
              Finally, every program is threatened constantly by software patents.
            States should not allow patents to restrict development and use of
            software on general-purpose computers, but in those that do, we wish to
            avoid the special danger that patents applied to a free program could
            make it effectively proprietary.  To prevent this, the GPL assures that
            patents cannot be used to render the program non-free.
            
              The precise terms and conditions for copying, distribution and
            modification follow.
            
                                   TERMS AND CONDITIONS
            
              0. Definitions.
            
              "This License" refers to version 3 of the GNU General Public License.
            
              "Copyright" also means copyright-like laws that apply to other kinds of
            works, such as semiconductor masks.
            
              "The Program" refers to any copyrightable work licensed under this
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                        How to Apply These Terms to Your New Programs
            
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            */

            File 5 of 5: NoProtocolFeeLiquidityBootstrappingPool
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            pragma experimental ABIEncoderV2;
            import "@balancer-labs/v2-solidity-utils/contracts/math/FixedPoint.sol";
            import "@balancer-labs/v2-solidity-utils/contracts/helpers/InputHelpers.sol";
            import "@balancer-labs/v2-pool-utils/contracts/BaseMinimalSwapInfoPool.sol";
            import "./WeightedMath.sol";
            import "./WeightedPoolUserDataHelpers.sol";
            /**
             * @dev Base class for WeightedPools containing swap, join and exit logic, but leaving storage and management of
             * the weights to subclasses. Derived contracts can choose to make weights immutable, mutable, or even dynamic
             *  based on local or external logic.
             */
            abstract contract BaseWeightedPool is BaseMinimalSwapInfoPool, WeightedMath {
                using FixedPoint for uint256;
                using WeightedPoolUserDataHelpers for bytes;
                uint256 private _lastInvariant;
                enum JoinKind { INIT, EXACT_TOKENS_IN_FOR_BPT_OUT, TOKEN_IN_FOR_EXACT_BPT_OUT }
                enum ExitKind { EXACT_BPT_IN_FOR_ONE_TOKEN_OUT, EXACT_BPT_IN_FOR_TOKENS_OUT, BPT_IN_FOR_EXACT_TOKENS_OUT }
                constructor(
                    IVault vault,
                    string memory name,
                    string memory symbol,
                    IERC20[] memory tokens,
                    address[] memory assetManagers,
                    uint256 swapFeePercentage,
                    uint256 pauseWindowDuration,
                    uint256 bufferPeriodDuration,
                    address owner
                )
                    BasePool(
                        vault,
                        // Given BaseMinimalSwapInfoPool supports both of these specializations, and this Pool never registers or
                        // deregisters any tokens after construction, picking Two Token when the Pool only has two tokens is free
                        // gas savings.
                        tokens.length == 2 ? IVault.PoolSpecialization.TWO_TOKEN : IVault.PoolSpecialization.MINIMAL_SWAP_INFO,
                        name,
                        symbol,
                        tokens,
                        assetManagers,
                        swapFeePercentage,
                        pauseWindowDuration,
                        bufferPeriodDuration,
                        owner
                    )
                {
                    // solhint-disable-previous-line no-empty-blocks
                }
                // Virtual functions
                /**
                 * @dev Returns the normalized weight of `token`. Weights are fixed point numbers that sum to FixedPoint.ONE.
                 */
                function _getNormalizedWeight(IERC20 token) internal view virtual returns (uint256);
                /**
                 * @dev Returns all normalized weights, in the same order as the Pool's tokens.
                 */
                function _getNormalizedWeights() internal view virtual returns (uint256[] memory);
                /**
                 * @dev Returns all normalized weights, in the same order as the Pool's tokens, along with the index of the token
                 * with the highest weight.
                 */
                function _getNormalizedWeightsAndMaxWeightIndex() internal view virtual returns (uint256[] memory, uint256);
                function getLastInvariant() external view returns (uint256) {
                    return _lastInvariant;
                }
                /**
                 * @dev Returns the current value of the invariant.
                 */
                function getInvariant() public view returns (uint256) {
                    (, uint256[] memory balances, ) = getVault().getPoolTokens(getPoolId());
                    // Since the Pool hooks always work with upscaled balances, we manually
                    // upscale here for consistency
                    _upscaleArray(balances, _scalingFactors());
                    (uint256[] memory normalizedWeights, ) = _getNormalizedWeightsAndMaxWeightIndex();
                    return WeightedMath._calculateInvariant(normalizedWeights, balances);
                }
                function getNormalizedWeights() external view returns (uint256[] memory) {
                    return _getNormalizedWeights();
                }
                // Base Pool handlers
                // Swap
                function _onSwapGivenIn(
                    SwapRequest memory swapRequest,
                    uint256 currentBalanceTokenIn,
                    uint256 currentBalanceTokenOut
                ) internal view virtual override whenNotPaused returns (uint256) {
                    // Swaps are disabled while the contract is paused.
                    return
                        WeightedMath._calcOutGivenIn(
                            currentBalanceTokenIn,
                            _getNormalizedWeight(swapRequest.tokenIn),
                            currentBalanceTokenOut,
                            _getNormalizedWeight(swapRequest.tokenOut),
                            swapRequest.amount
                        );
                }
                function _onSwapGivenOut(
                    SwapRequest memory swapRequest,
                    uint256 currentBalanceTokenIn,
                    uint256 currentBalanceTokenOut
                ) internal view virtual override whenNotPaused returns (uint256) {
                    // Swaps are disabled while the contract is paused.
                    return
                        WeightedMath._calcInGivenOut(
                            currentBalanceTokenIn,
                            _getNormalizedWeight(swapRequest.tokenIn),
                            currentBalanceTokenOut,
                            _getNormalizedWeight(swapRequest.tokenOut),
                            swapRequest.amount
                        );
                }
                // Initialize
                function _onInitializePool(
                    bytes32,
                    address,
                    address,
                    uint256[] memory scalingFactors,
                    bytes memory userData
                ) internal virtual override whenNotPaused returns (uint256, uint256[] memory) {
                    // It would be strange for the Pool to be paused before it is initialized, but for consistency we prevent
                    // initialization in this case.
                    JoinKind kind = userData.joinKind();
                    _require(kind == JoinKind.INIT, Errors.UNINITIALIZED);
                    uint256[] memory amountsIn = userData.initialAmountsIn();
                    InputHelpers.ensureInputLengthMatch(_getTotalTokens(), amountsIn.length);
                    _upscaleArray(amountsIn, scalingFactors);
                    (uint256[] memory normalizedWeights, ) = _getNormalizedWeightsAndMaxWeightIndex();
                    uint256 invariantAfterJoin = WeightedMath._calculateInvariant(normalizedWeights, amountsIn);
                    // Set the initial BPT to the value of the invariant times the number of tokens. This makes BPT supply more
                    // consistent in Pools with similar compositions but different number of tokens.
                    uint256 bptAmountOut = Math.mul(invariantAfterJoin, _getTotalTokens());
                    _lastInvariant = invariantAfterJoin;
                    return (bptAmountOut, amountsIn);
                }
                // Join
                function _onJoinPool(
                    bytes32,
                    address,
                    address,
                    uint256[] memory balances,
                    uint256,
                    uint256 protocolSwapFeePercentage,
                    uint256[] memory scalingFactors,
                    bytes memory userData
                )
                    internal
                    virtual
                    override
                    whenNotPaused
                    returns (
                        uint256,
                        uint256[] memory,
                        uint256[] memory
                    )
                {
                    // All joins are disabled while the contract is paused.
                    (uint256[] memory normalizedWeights, uint256 maxWeightTokenIndex) = _getNormalizedWeightsAndMaxWeightIndex();
                    // Due protocol swap fee amounts are computed by measuring the growth of the invariant between the previous join
                    // or exit event and now - the invariant's growth is due exclusively to swap fees. This avoids spending gas
                    // computing them on each individual swap
                    uint256 invariantBeforeJoin = WeightedMath._calculateInvariant(normalizedWeights, balances);
                    uint256[] memory dueProtocolFeeAmounts = _getDueProtocolFeeAmounts(
                        balances,
                        normalizedWeights,
                        maxWeightTokenIndex,
                        _lastInvariant,
                        invariantBeforeJoin,
                        protocolSwapFeePercentage
                    );
                    // Update current balances by subtracting the protocol fee amounts
                    _mutateAmounts(balances, dueProtocolFeeAmounts, FixedPoint.sub);
                    (uint256 bptAmountOut, uint256[] memory amountsIn) = _doJoin(
                        balances,
                        normalizedWeights,
                        scalingFactors,
                        userData
                    );
                    // Update the invariant with the balances the Pool will have after the join, in order to compute the
                    // protocol swap fee amounts due in future joins and exits.
                    _lastInvariant = _invariantAfterJoin(balances, amountsIn, normalizedWeights);
                    return (bptAmountOut, amountsIn, dueProtocolFeeAmounts);
                }
                function _doJoin(
                    uint256[] memory balances,
                    uint256[] memory normalizedWeights,
                    uint256[] memory scalingFactors,
                    bytes memory userData
                ) private view returns (uint256, uint256[] memory) {
                    JoinKind kind = userData.joinKind();
                    if (kind == JoinKind.EXACT_TOKENS_IN_FOR_BPT_OUT) {
                        return _joinExactTokensInForBPTOut(balances, normalizedWeights, scalingFactors, userData);
                    } else if (kind == JoinKind.TOKEN_IN_FOR_EXACT_BPT_OUT) {
                        return _joinTokenInForExactBPTOut(balances, normalizedWeights, userData);
                    } else {
                        _revert(Errors.UNHANDLED_JOIN_KIND);
                    }
                }
                function _joinExactTokensInForBPTOut(
                    uint256[] memory balances,
                    uint256[] memory normalizedWeights,
                    uint256[] memory scalingFactors,
                    bytes memory userData
                ) private view returns (uint256, uint256[] memory) {
                    (uint256[] memory amountsIn, uint256 minBPTAmountOut) = userData.exactTokensInForBptOut();
                    InputHelpers.ensureInputLengthMatch(_getTotalTokens(), amountsIn.length);
                    _upscaleArray(amountsIn, scalingFactors);
                    uint256 bptAmountOut = WeightedMath._calcBptOutGivenExactTokensIn(
                        balances,
                        normalizedWeights,
                        amountsIn,
                        totalSupply(),
                        getSwapFeePercentage()
                    );
                    _require(bptAmountOut >= minBPTAmountOut, Errors.BPT_OUT_MIN_AMOUNT);
                    return (bptAmountOut, amountsIn);
                }
                function _joinTokenInForExactBPTOut(
                    uint256[] memory balances,
                    uint256[] memory normalizedWeights,
                    bytes memory userData
                ) private view returns (uint256, uint256[] memory) {
                    (uint256 bptAmountOut, uint256 tokenIndex) = userData.tokenInForExactBptOut();
                    // Note that there is no maximum amountIn parameter: this is handled by `IVault.joinPool`.
                    _require(tokenIndex < _getTotalTokens(), Errors.OUT_OF_BOUNDS);
                    uint256[] memory amountsIn = new uint256[](_getTotalTokens());
                    amountsIn[tokenIndex] = WeightedMath._calcTokenInGivenExactBptOut(
                        balances[tokenIndex],
                        normalizedWeights[tokenIndex],
                        bptAmountOut,
                        totalSupply(),
                        getSwapFeePercentage()
                    );
                    return (bptAmountOut, amountsIn);
                }
                // Exit
                function _onExitPool(
                    bytes32,
                    address,
                    address,
                    uint256[] memory balances,
                    uint256,
                    uint256 protocolSwapFeePercentage,
                    uint256[] memory scalingFactors,
                    bytes memory userData
                )
                    internal
                    virtual
                    override
                    returns (
                        uint256 bptAmountIn,
                        uint256[] memory amountsOut,
                        uint256[] memory dueProtocolFeeAmounts
                    )
                {
                    (uint256[] memory normalizedWeights, uint256 maxWeightTokenIndex) = _getNormalizedWeightsAndMaxWeightIndex();
                    // Exits are not completely disabled while the contract is paused: proportional exits (exact BPT in for tokens
                    // out) remain functional.
                    if (_isNotPaused()) {
                        // Due protocol swap fee amounts are computed by measuring the growth of the invariant between the previous
                        // join or exit event and now - the invariant's growth is due exclusively to swap fees. This avoids
                        // spending gas calculating the fees on each individual swap.
                        uint256 invariantBeforeExit = WeightedMath._calculateInvariant(normalizedWeights, balances);
                        dueProtocolFeeAmounts = _getDueProtocolFeeAmounts(
                            balances,
                            normalizedWeights,
                            maxWeightTokenIndex,
                            _lastInvariant,
                            invariantBeforeExit,
                            protocolSwapFeePercentage
                        );
                        // Update current balances by subtracting the protocol fee amounts
                        _mutateAmounts(balances, dueProtocolFeeAmounts, FixedPoint.sub);
                    } else {
                        // If the contract is paused, swap protocol fee amounts are not charged to avoid extra calculations and
                        // reduce the potential for errors.
                        dueProtocolFeeAmounts = new uint256[](_getTotalTokens());
                    }
                    (bptAmountIn, amountsOut) = _doExit(balances, normalizedWeights, scalingFactors, userData);
                    // Update the invariant with the balances the Pool will have after the exit, in order to compute the
                    // protocol swap fees due in future joins and exits.
                    _lastInvariant = _invariantAfterExit(balances, amountsOut, normalizedWeights);
                    return (bptAmountIn, amountsOut, dueProtocolFeeAmounts);
                }
                function _doExit(
                    uint256[] memory balances,
                    uint256[] memory normalizedWeights,
                    uint256[] memory scalingFactors,
                    bytes memory userData
                ) private view returns (uint256, uint256[] memory) {
                    ExitKind kind = userData.exitKind();
                    if (kind == ExitKind.EXACT_BPT_IN_FOR_ONE_TOKEN_OUT) {
                        return _exitExactBPTInForTokenOut(balances, normalizedWeights, userData);
                    } else if (kind == ExitKind.EXACT_BPT_IN_FOR_TOKENS_OUT) {
                        return _exitExactBPTInForTokensOut(balances, userData);
                    } else {
                        // ExitKind.BPT_IN_FOR_EXACT_TOKENS_OUT
                        return _exitBPTInForExactTokensOut(balances, normalizedWeights, scalingFactors, userData);
                    }
                }
                function _exitExactBPTInForTokenOut(
                    uint256[] memory balances,
                    uint256[] memory normalizedWeights,
                    bytes memory userData
                ) private view whenNotPaused returns (uint256, uint256[] memory) {
                    // This exit function is disabled if the contract is paused.
                    (uint256 bptAmountIn, uint256 tokenIndex) = userData.exactBptInForTokenOut();
                    // Note that there is no minimum amountOut parameter: this is handled by `IVault.exitPool`.
                    _require(tokenIndex < _getTotalTokens(), Errors.OUT_OF_BOUNDS);
                    // We exit in a single token, so we initialize amountsOut with zeros
                    uint256[] memory amountsOut = new uint256[](_getTotalTokens());
                    // And then assign the result to the selected token
                    amountsOut[tokenIndex] = WeightedMath._calcTokenOutGivenExactBptIn(
                        balances[tokenIndex],
                        normalizedWeights[tokenIndex],
                        bptAmountIn,
                        totalSupply(),
                        getSwapFeePercentage()
                    );
                    return (bptAmountIn, amountsOut);
                }
                function _exitExactBPTInForTokensOut(uint256[] memory balances, bytes memory userData)
                    private
                    view
                    returns (uint256, uint256[] memory)
                {
                    // This exit function is the only one that is not disabled if the contract is paused: it remains unrestricted
                    // in an attempt to provide users with a mechanism to retrieve their tokens in case of an emergency.
                    // This particular exit function is the only one that remains available because it is the simplest one, and
                    // therefore the one with the lowest likelihood of errors.
                    uint256 bptAmountIn = userData.exactBptInForTokensOut();
                    // Note that there is no minimum amountOut parameter: this is handled by `IVault.exitPool`.
                    uint256[] memory amountsOut = WeightedMath._calcTokensOutGivenExactBptIn(balances, bptAmountIn, totalSupply());
                    return (bptAmountIn, amountsOut);
                }
                function _exitBPTInForExactTokensOut(
                    uint256[] memory balances,
                    uint256[] memory normalizedWeights,
                    uint256[] memory scalingFactors,
                    bytes memory userData
                ) private view whenNotPaused returns (uint256, uint256[] memory) {
                    // This exit function is disabled if the contract is paused.
                    (uint256[] memory amountsOut, uint256 maxBPTAmountIn) = userData.bptInForExactTokensOut();
                    InputHelpers.ensureInputLengthMatch(amountsOut.length, _getTotalTokens());
                    _upscaleArray(amountsOut, scalingFactors);
                    uint256 bptAmountIn = WeightedMath._calcBptInGivenExactTokensOut(
                        balances,
                        normalizedWeights,
                        amountsOut,
                        totalSupply(),
                        getSwapFeePercentage()
                    );
                    _require(bptAmountIn <= maxBPTAmountIn, Errors.BPT_IN_MAX_AMOUNT);
                    return (bptAmountIn, amountsOut);
                }
                // Helpers
                function _getDueProtocolFeeAmounts(
                    uint256[] memory balances,
                    uint256[] memory normalizedWeights,
                    uint256 maxWeightTokenIndex,
                    uint256 previousInvariant,
                    uint256 currentInvariant,
                    uint256 protocolSwapFeePercentage
                ) private view returns (uint256[] memory) {
                    // Initialize with zeros
                    uint256[] memory dueProtocolFeeAmounts = new uint256[](_getTotalTokens());
                    // Early return if the protocol swap fee percentage is zero, saving gas.
                    if (protocolSwapFeePercentage == 0) {
                        return dueProtocolFeeAmounts;
                    }
                    // The protocol swap fees are always paid using the token with the largest weight in the Pool. As this is the
                    // token that is expected to have the largest balance, using it to pay fees should not unbalance the Pool.
                    dueProtocolFeeAmounts[maxWeightTokenIndex] = WeightedMath._calcDueTokenProtocolSwapFeeAmount(
                        balances[maxWeightTokenIndex],
                        normalizedWeights[maxWeightTokenIndex],
                        previousInvariant,
                        currentInvariant,
                        protocolSwapFeePercentage
                    );
                    return dueProtocolFeeAmounts;
                }
                /**
                 * @dev Returns the value of the invariant given `balances`, assuming they are increased by `amountsIn`. All
                 * amounts are expected to be upscaled.
                 */
                function _invariantAfterJoin(
                    uint256[] memory balances,
                    uint256[] memory amountsIn,
                    uint256[] memory normalizedWeights
                ) private view returns (uint256) {
                    _mutateAmounts(balances, amountsIn, FixedPoint.add);
                    return WeightedMath._calculateInvariant(normalizedWeights, balances);
                }
                function _invariantAfterExit(
                    uint256[] memory balances,
                    uint256[] memory amountsOut,
                    uint256[] memory normalizedWeights
                ) private view returns (uint256) {
                    _mutateAmounts(balances, amountsOut, FixedPoint.sub);
                    return WeightedMath._calculateInvariant(normalizedWeights, balances);
                }
                /**
                 * @dev Mutates `amounts` by applying `mutation` with each entry in `arguments`.
                 *
                 * Equivalent to `amounts = amounts.map(mutation)`.
                 */
                function _mutateAmounts(
                    uint256[] memory toMutate,
                    uint256[] memory arguments,
                    function(uint256, uint256) pure returns (uint256) mutation
                ) private view {
                    for (uint256 i = 0; i < _getTotalTokens(); ++i) {
                        toMutate[i] = mutation(toMutate[i], arguments[i]);
                    }
                }
                /**
                 * @dev This function returns the appreciation of one BPT relative to the
                 * underlying tokens. This starts at 1 when the pool is created and grows over time
                 */
                function getRate() public view returns (uint256) {
                    // The initial BPT supply is equal to the invariant times the number of tokens.
                    return Math.mul(getInvariant(), _getTotalTokens()).divDown(totalSupply());
                }
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            import "./LogExpMath.sol";
            import "../helpers/BalancerErrors.sol";
            /* solhint-disable private-vars-leading-underscore */
            library FixedPoint {
                uint256 internal constant ONE = 1e18; // 18 decimal places
                uint256 internal constant MAX_POW_RELATIVE_ERROR = 10000; // 10^(-14)
                // Minimum base for the power function when the exponent is 'free' (larger than ONE).
                uint256 internal constant MIN_POW_BASE_FREE_EXPONENT = 0.7e18;
                function add(uint256 a, uint256 b) internal pure returns (uint256) {
                    // Fixed Point addition is the same as regular checked addition
                    uint256 c = a + b;
                    _require(c >= a, Errors.ADD_OVERFLOW);
                    return c;
                }
                function sub(uint256 a, uint256 b) internal pure returns (uint256) {
                    // Fixed Point addition is the same as regular checked addition
                    _require(b <= a, Errors.SUB_OVERFLOW);
                    uint256 c = a - b;
                    return c;
                }
                function mulDown(uint256 a, uint256 b) internal pure returns (uint256) {
                    uint256 product = a * b;
                    _require(a == 0 || product / a == b, Errors.MUL_OVERFLOW);
                    return product / ONE;
                }
                function mulUp(uint256 a, uint256 b) internal pure returns (uint256) {
                    uint256 product = a * b;
                    _require(a == 0 || product / a == b, Errors.MUL_OVERFLOW);
                    if (product == 0) {
                        return 0;
                    } else {
                        // The traditional divUp formula is:
                        // divUp(x, y) := (x + y - 1) / y
                        // To avoid intermediate overflow in the addition, we distribute the division and get:
                        // divUp(x, y) := (x - 1) / y + 1
                        // Note that this requires x != 0, which we already tested for.
                        return ((product - 1) / ONE) + 1;
                    }
                }
                function divDown(uint256 a, uint256 b) internal pure returns (uint256) {
                    _require(b != 0, Errors.ZERO_DIVISION);
                    if (a == 0) {
                        return 0;
                    } else {
                        uint256 aInflated = a * ONE;
                        _require(aInflated / a == ONE, Errors.DIV_INTERNAL); // mul overflow
                        return aInflated / b;
                    }
                }
                function divUp(uint256 a, uint256 b) internal pure returns (uint256) {
                    _require(b != 0, Errors.ZERO_DIVISION);
                    if (a == 0) {
                        return 0;
                    } else {
                        uint256 aInflated = a * ONE;
                        _require(aInflated / a == ONE, Errors.DIV_INTERNAL); // mul overflow
                        // The traditional divUp formula is:
                        // divUp(x, y) := (x + y - 1) / y
                        // To avoid intermediate overflow in the addition, we distribute the division and get:
                        // divUp(x, y) := (x - 1) / y + 1
                        // Note that this requires x != 0, which we already tested for.
                        return ((aInflated - 1) / b) + 1;
                    }
                }
                /**
                 * @dev Returns x^y, assuming both are fixed point numbers, rounding down. The result is guaranteed to not be above
                 * the true value (that is, the error function expected - actual is always positive).
                 */
                function powDown(uint256 x, uint256 y) internal pure returns (uint256) {
                    uint256 raw = LogExpMath.pow(x, y);
                    uint256 maxError = add(mulUp(raw, MAX_POW_RELATIVE_ERROR), 1);
                    if (raw < maxError) {
                        return 0;
                    } else {
                        return sub(raw, maxError);
                    }
                }
                /**
                 * @dev Returns x^y, assuming both are fixed point numbers, rounding up. The result is guaranteed to not be below
                 * the true value (that is, the error function expected - actual is always negative).
                 */
                function powUp(uint256 x, uint256 y) internal pure returns (uint256) {
                    uint256 raw = LogExpMath.pow(x, y);
                    uint256 maxError = add(mulUp(raw, MAX_POW_RELATIVE_ERROR), 1);
                    return add(raw, maxError);
                }
                /**
                 * @dev Returns the complement of a value (1 - x), capped to 0 if x is larger than 1.
                 *
                 * Useful when computing the complement for values with some level of relative error, as it strips this error and
                 * prevents intermediate negative values.
                 */
                function complement(uint256 x) internal pure returns (uint256) {
                    return (x < ONE) ? (ONE - x) : 0;
                }
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            import "../openzeppelin/IERC20.sol";
            import "./BalancerErrors.sol";
            library InputHelpers {
                function ensureInputLengthMatch(uint256 a, uint256 b) internal pure {
                    _require(a == b, Errors.INPUT_LENGTH_MISMATCH);
                }
                function ensureInputLengthMatch(
                    uint256 a,
                    uint256 b,
                    uint256 c
                ) internal pure {
                    _require(a == b && b == c, Errors.INPUT_LENGTH_MISMATCH);
                }
                function ensureArrayIsSorted(IERC20[] memory array) internal pure {
                    address[] memory addressArray;
                    // solhint-disable-next-line no-inline-assembly
                    assembly {
                        addressArray := array
                    }
                    ensureArrayIsSorted(addressArray);
                }
                function ensureArrayIsSorted(address[] memory array) internal pure {
                    if (array.length < 2) {
                        return;
                    }
                    address previous = array[0];
                    for (uint256 i = 1; i < array.length; ++i) {
                        address current = array[i];
                        _require(previous < current, Errors.UNSORTED_ARRAY);
                        previous = current;
                    }
                }
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            pragma experimental ABIEncoderV2;
            import "./BasePool.sol";
            import "@balancer-labs/v2-vault/contracts/interfaces/IMinimalSwapInfoPool.sol";
            /**
             * @dev Extension of `BasePool`, adding a handler for `IMinimalSwapInfoPool.onSwap`.
             *
             * Derived contracts must call `BasePool`'s constructor, and implement `_onSwapGivenIn` and `_onSwapGivenOut` along with
             * `BasePool`'s virtual functions. Inheriting from this contract lets derived contracts choose the Two Token or Minimal
             * Swap Info specialization settings.
             */
            abstract contract BaseMinimalSwapInfoPool is IMinimalSwapInfoPool, BasePool {
                // Swap Hooks
                function onSwap(
                    SwapRequest memory request,
                    uint256 balanceTokenIn,
                    uint256 balanceTokenOut
                ) public virtual override returns (uint256) {
                    uint256 scalingFactorTokenIn = _scalingFactor(request.tokenIn);
                    uint256 scalingFactorTokenOut = _scalingFactor(request.tokenOut);
                    if (request.kind == IVault.SwapKind.GIVEN_IN) {
                        // Fees are subtracted before scaling, to reduce the complexity of the rounding direction analysis.
                        request.amount = _subtractSwapFeeAmount(request.amount);
                        // All token amounts are upscaled.
                        balanceTokenIn = _upscale(balanceTokenIn, scalingFactorTokenIn);
                        balanceTokenOut = _upscale(balanceTokenOut, scalingFactorTokenOut);
                        request.amount = _upscale(request.amount, scalingFactorTokenIn);
                        uint256 amountOut = _onSwapGivenIn(request, balanceTokenIn, balanceTokenOut);
                        // amountOut tokens are exiting the Pool, so we round down.
                        return _downscaleDown(amountOut, scalingFactorTokenOut);
                    } else {
                        // All token amounts are upscaled.
                        balanceTokenIn = _upscale(balanceTokenIn, scalingFactorTokenIn);
                        balanceTokenOut = _upscale(balanceTokenOut, scalingFactorTokenOut);
                        request.amount = _upscale(request.amount, scalingFactorTokenOut);
                        uint256 amountIn = _onSwapGivenOut(request, balanceTokenIn, balanceTokenOut);
                        // amountIn tokens are entering the Pool, so we round up.
                        amountIn = _downscaleUp(amountIn, scalingFactorTokenIn);
                        // Fees are added after scaling happens, to reduce the complexity of the rounding direction analysis.
                        return _addSwapFeeAmount(amountIn);
                    }
                }
                /*
                 * @dev Called when a swap with the Pool occurs, where the amount of tokens entering the Pool is known.
                 *
                 * Returns the amount of tokens that will be taken from the Pool in return.
                 *
                 * All amounts inside `swapRequest`, `balanceTokenIn` and `balanceTokenOut` are upscaled. The swap fee has already
                 * been deducted from `swapRequest.amount`.
                 *
                 * The return value is also considered upscaled, and will be downscaled (rounding down) before returning it to the
                 * Vault.
                 */
                function _onSwapGivenIn(
                    SwapRequest memory swapRequest,
                    uint256 balanceTokenIn,
                    uint256 balanceTokenOut
                ) internal virtual returns (uint256);
                /*
                 * @dev Called when a swap with the Pool occurs, where the amount of tokens exiting the Pool is known.
                 *
                 * Returns the amount of tokens that will be granted to the Pool in return.
                 *
                 * All amounts inside `swapRequest`, `balanceTokenIn` and `balanceTokenOut` are upscaled.
                 *
                 * The return value is also considered upscaled, and will be downscaled (rounding up) before applying the swap fee
                 * and returning it to the Vault.
                 */
                function _onSwapGivenOut(
                    SwapRequest memory swapRequest,
                    uint256 balanceTokenIn,
                    uint256 balanceTokenOut
                ) internal virtual returns (uint256);
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            import "@balancer-labs/v2-solidity-utils/contracts/math/FixedPoint.sol";
            import "@balancer-labs/v2-solidity-utils/contracts/math/Math.sol";
            import "@balancer-labs/v2-solidity-utils/contracts/helpers/InputHelpers.sol";
            /* solhint-disable private-vars-leading-underscore */
            contract WeightedMath {
                using FixedPoint for uint256;
                // A minimum normalized weight imposes a maximum weight ratio. We need this due to limitations in the
                // implementation of the power function, as these ratios are often exponents.
                uint256 internal constant _MIN_WEIGHT = 0.01e18;
                // Having a minimum normalized weight imposes a limit on the maximum number of tokens;
                // i.e., the largest possible pool is one where all tokens have exactly the minimum weight.
                uint256 internal constant _MAX_WEIGHTED_TOKENS = 100;
                // Pool limits that arise from limitations in the fixed point power function (and the imposed 1:100 maximum weight
                // ratio).
                // Swap limits: amounts swapped may not be larger than this percentage of total balance.
                uint256 internal constant _MAX_IN_RATIO = 0.3e18;
                uint256 internal constant _MAX_OUT_RATIO = 0.3e18;
                // Invariant growth limit: non-proportional joins cannot cause the invariant to increase by more than this ratio.
                uint256 internal constant _MAX_INVARIANT_RATIO = 3e18;
                // Invariant shrink limit: non-proportional exits cannot cause the invariant to decrease by less than this ratio.
                uint256 internal constant _MIN_INVARIANT_RATIO = 0.7e18;
                // Invariant is used to collect protocol swap fees by comparing its value between two times.
                // So we can round always to the same direction. It is also used to initiate the BPT amount
                // and, because there is a minimum BPT, we round down the invariant.
                function _calculateInvariant(uint256[] memory normalizedWeights, uint256[] memory balances)
                    internal
                    pure
                    returns (uint256 invariant)
                {
                    /**********************************************************************************************
                    // invariant               _____                                                             //
                    // wi = weight index i      | |      wi                                                      //
                    // bi = balance index i     | |  bi ^   = i                                                  //
                    // i = invariant                                                                             //
                    **********************************************************************************************/
                    invariant = FixedPoint.ONE;
                    for (uint256 i = 0; i < normalizedWeights.length; i++) {
                        invariant = invariant.mulDown(balances[i].powDown(normalizedWeights[i]));
                    }
                    _require(invariant > 0, Errors.ZERO_INVARIANT);
                }
                // Computes how many tokens can be taken out of a pool if `amountIn` are sent, given the
                // current balances and weights.
                function _calcOutGivenIn(
                    uint256 balanceIn,
                    uint256 weightIn,
                    uint256 balanceOut,
                    uint256 weightOut,
                    uint256 amountIn
                ) internal pure returns (uint256) {
                    /**********************************************************************************************
                    // outGivenIn                                                                                //
                    // aO = amountOut                                                                            //
                    // bO = balanceOut                                                                           //
                    // bI = balanceIn              /      /            bI             \\    (wI / wO) \\           //
                    // aI = amountIn    aO = bO * |  1 - | --------------------------  | ^            |          //
                    // wI = weightIn               \\      \\       ( bI + aI )         /              /           //
                    // wO = weightOut                                                                            //
                    **********************************************************************************************/
                    // Amount out, so we round down overall.
                    // The multiplication rounds down, and the subtrahend (power) rounds up (so the base rounds up too).
                    // Because bI / (bI + aI) <= 1, the exponent rounds down.
                    // Cannot exceed maximum in ratio
                    _require(amountIn <= balanceIn.mulDown(_MAX_IN_RATIO), Errors.MAX_IN_RATIO);
                    uint256 denominator = balanceIn.add(amountIn);
                    uint256 base = balanceIn.divUp(denominator);
                    uint256 exponent = weightIn.divDown(weightOut);
                    uint256 power = base.powUp(exponent);
                    return balanceOut.mulDown(power.complement());
                }
                // Computes how many tokens must be sent to a pool in order to take `amountOut`, given the
                // current balances and weights.
                function _calcInGivenOut(
                    uint256 balanceIn,
                    uint256 weightIn,
                    uint256 balanceOut,
                    uint256 weightOut,
                    uint256 amountOut
                ) internal pure returns (uint256) {
                    /**********************************************************************************************
                    // inGivenOut                                                                                //
                    // aO = amountOut                                                                            //
                    // bO = balanceOut                                                                           //
                    // bI = balanceIn              /  /            bO             \\    (wO / wI)      \\          //
                    // aI = amountIn    aI = bI * |  | --------------------------  | ^            - 1  |         //
                    // wI = weightIn               \\  \\       ( bO - aO )         /                   /          //
                    // wO = weightOut                                                                            //
                    **********************************************************************************************/
                    // Amount in, so we round up overall.
                    // The multiplication rounds up, and the power rounds up (so the base rounds up too).
                    // Because b0 / (b0 - a0) >= 1, the exponent rounds up.
                    // Cannot exceed maximum out ratio
                    _require(amountOut <= balanceOut.mulDown(_MAX_OUT_RATIO), Errors.MAX_OUT_RATIO);
                    uint256 base = balanceOut.divUp(balanceOut.sub(amountOut));
                    uint256 exponent = weightOut.divUp(weightIn);
                    uint256 power = base.powUp(exponent);
                    // Because the base is larger than one (and the power rounds up), the power should always be larger than one, so
                    // the following subtraction should never revert.
                    uint256 ratio = power.sub(FixedPoint.ONE);
                    return balanceIn.mulUp(ratio);
                }
                function _calcBptOutGivenExactTokensIn(
                    uint256[] memory balances,
                    uint256[] memory normalizedWeights,
                    uint256[] memory amountsIn,
                    uint256 bptTotalSupply,
                    uint256 swapFeePercentage
                ) internal pure returns (uint256) {
                    // BPT out, so we round down overall.
                    uint256[] memory balanceRatiosWithFee = new uint256[](amountsIn.length);
                    uint256 invariantRatioWithFees = 0;
                    for (uint256 i = 0; i < balances.length; i++) {
                        balanceRatiosWithFee[i] = balances[i].add(amountsIn[i]).divDown(balances[i]);
                        invariantRatioWithFees = invariantRatioWithFees.add(balanceRatiosWithFee[i].mulDown(normalizedWeights[i]));
                    }
                    uint256 invariantRatio = FixedPoint.ONE;
                    for (uint256 i = 0; i < balances.length; i++) {
                        uint256 amountInWithoutFee;
                        if (balanceRatiosWithFee[i] > invariantRatioWithFees) {
                            uint256 nonTaxableAmount = balances[i].mulDown(invariantRatioWithFees.sub(FixedPoint.ONE));
                            uint256 taxableAmount = amountsIn[i].sub(nonTaxableAmount);
                            amountInWithoutFee = nonTaxableAmount.add(taxableAmount.mulDown(FixedPoint.ONE.sub(swapFeePercentage)));
                        } else {
                            amountInWithoutFee = amountsIn[i];
                        }
                        uint256 balanceRatio = balances[i].add(amountInWithoutFee).divDown(balances[i]);
                        invariantRatio = invariantRatio.mulDown(balanceRatio.powDown(normalizedWeights[i]));
                    }
                    if (invariantRatio > FixedPoint.ONE) {
                        return bptTotalSupply.mulDown(invariantRatio.sub(FixedPoint.ONE));
                    } else {
                        return 0;
                    }
                }
                function _calcTokenInGivenExactBptOut(
                    uint256 balance,
                    uint256 normalizedWeight,
                    uint256 bptAmountOut,
                    uint256 bptTotalSupply,
                    uint256 swapFeePercentage
                ) internal pure returns (uint256) {
                    /******************************************************************************************
                    // tokenInForExactBPTOut                                                                 //
                    // a = amountIn                                                                          //
                    // b = balance                      /  /    totalBPT + bptOut      \\    (1 / w)       \\  //
                    // bptOut = bptAmountOut   a = b * |  | --------------------------  | ^          - 1  |  //
                    // bpt = totalBPT                   \\  \\       totalBPT            /                  /  //
                    // w = weight                                                                            //
                    ******************************************************************************************/
                    // Token in, so we round up overall.
                    // Calculate the factor by which the invariant will increase after minting BPTAmountOut
                    uint256 invariantRatio = bptTotalSupply.add(bptAmountOut).divUp(bptTotalSupply);
                    _require(invariantRatio <= _MAX_INVARIANT_RATIO, Errors.MAX_OUT_BPT_FOR_TOKEN_IN);
                    // Calculate by how much the token balance has to increase to match the invariantRatio
                    uint256 balanceRatio = invariantRatio.powUp(FixedPoint.ONE.divUp(normalizedWeight));
                    uint256 amountInWithoutFee = balance.mulUp(balanceRatio.sub(FixedPoint.ONE));
                    // We can now compute how much extra balance is being deposited and used in virtual swaps, and charge swap fees
                    // accordingly.
                    uint256 taxablePercentage = normalizedWeight.complement();
                    uint256 taxableAmount = amountInWithoutFee.mulUp(taxablePercentage);
                    uint256 nonTaxableAmount = amountInWithoutFee.sub(taxableAmount);
                    return nonTaxableAmount.add(taxableAmount.divUp(FixedPoint.ONE.sub(swapFeePercentage)));
                }
                function _calcBptInGivenExactTokensOut(
                    uint256[] memory balances,
                    uint256[] memory normalizedWeights,
                    uint256[] memory amountsOut,
                    uint256 bptTotalSupply,
                    uint256 swapFeePercentage
                ) internal pure returns (uint256) {
                    // BPT in, so we round up overall.
                    uint256[] memory balanceRatiosWithoutFee = new uint256[](amountsOut.length);
                    uint256 invariantRatioWithoutFees = 0;
                    for (uint256 i = 0; i < balances.length; i++) {
                        balanceRatiosWithoutFee[i] = balances[i].sub(amountsOut[i]).divUp(balances[i]);
                        invariantRatioWithoutFees = invariantRatioWithoutFees.add(
                            balanceRatiosWithoutFee[i].mulUp(normalizedWeights[i])
                        );
                    }
                    uint256 invariantRatio = FixedPoint.ONE;
                    for (uint256 i = 0; i < balances.length; i++) {
                        // Swap fees are typically charged on 'token in', but there is no 'token in' here, so we apply it to
                        // 'token out'. This results in slightly larger price impact.
                        uint256 amountOutWithFee;
                        if (invariantRatioWithoutFees > balanceRatiosWithoutFee[i]) {
                            uint256 nonTaxableAmount = balances[i].mulDown(invariantRatioWithoutFees.complement());
                            uint256 taxableAmount = amountsOut[i].sub(nonTaxableAmount);
                            amountOutWithFee = nonTaxableAmount.add(taxableAmount.divUp(FixedPoint.ONE.sub(swapFeePercentage)));
                        } else {
                            amountOutWithFee = amountsOut[i];
                        }
                        uint256 balanceRatio = balances[i].sub(amountOutWithFee).divDown(balances[i]);
                        invariantRatio = invariantRatio.mulDown(balanceRatio.powDown(normalizedWeights[i]));
                    }
                    return bptTotalSupply.mulUp(invariantRatio.complement());
                }
                function _calcTokenOutGivenExactBptIn(
                    uint256 balance,
                    uint256 normalizedWeight,
                    uint256 bptAmountIn,
                    uint256 bptTotalSupply,
                    uint256 swapFeePercentage
                ) internal pure returns (uint256) {
                    /*****************************************************************************************
                    // exactBPTInForTokenOut                                                                //
                    // a = amountOut                                                                        //
                    // b = balance                     /      /    totalBPT - bptIn       \\    (1 / w)  \\   //
                    // bptIn = bptAmountIn    a = b * |  1 - | --------------------------  | ^           |  //
                    // bpt = totalBPT                  \\      \\       totalBPT            /             /   //
                    // w = weight                                                                           //
                    *****************************************************************************************/
                    // Token out, so we round down overall. The multiplication rounds down, but the power rounds up (so the base
                    // rounds up). Because (totalBPT - bptIn) / totalBPT <= 1, the exponent rounds down.
                    // Calculate the factor by which the invariant will decrease after burning BPTAmountIn
                    uint256 invariantRatio = bptTotalSupply.sub(bptAmountIn).divUp(bptTotalSupply);
                    _require(invariantRatio >= _MIN_INVARIANT_RATIO, Errors.MIN_BPT_IN_FOR_TOKEN_OUT);
                    // Calculate by how much the token balance has to decrease to match invariantRatio
                    uint256 balanceRatio = invariantRatio.powUp(FixedPoint.ONE.divDown(normalizedWeight));
                    // Because of rounding up, balanceRatio can be greater than one. Using complement prevents reverts.
                    uint256 amountOutWithoutFee = balance.mulDown(balanceRatio.complement());
                    // We can now compute how much excess balance is being withdrawn as a result of the virtual swaps, which result
                    // in swap fees.
                    uint256 taxablePercentage = normalizedWeight.complement();
                    // Swap fees are typically charged on 'token in', but there is no 'token in' here, so we apply it
                    // to 'token out'. This results in slightly larger price impact. Fees are rounded up.
                    uint256 taxableAmount = amountOutWithoutFee.mulUp(taxablePercentage);
                    uint256 nonTaxableAmount = amountOutWithoutFee.sub(taxableAmount);
                    return nonTaxableAmount.add(taxableAmount.mulDown(FixedPoint.ONE.sub(swapFeePercentage)));
                }
                function _calcTokensOutGivenExactBptIn(
                    uint256[] memory balances,
                    uint256 bptAmountIn,
                    uint256 totalBPT
                ) internal pure returns (uint256[] memory) {
                    /**********************************************************************************************
                    // exactBPTInForTokensOut                                                                    //
                    // (per token)                                                                               //
                    // aO = amountOut                  /        bptIn         \\                                  //
                    // b = balance           a0 = b * | ---------------------  |                                 //
                    // bptIn = bptAmountIn             \\       totalBPT       /                                  //
                    // bpt = totalBPT                                                                            //
                    **********************************************************************************************/
                    // Since we're computing an amount out, we round down overall. This means rounding down on both the
                    // multiplication and division.
                    uint256 bptRatio = bptAmountIn.divDown(totalBPT);
                    uint256[] memory amountsOut = new uint256[](balances.length);
                    for (uint256 i = 0; i < balances.length; i++) {
                        amountsOut[i] = balances[i].mulDown(bptRatio);
                    }
                    return amountsOut;
                }
                function _calcDueTokenProtocolSwapFeeAmount(
                    uint256 balance,
                    uint256 normalizedWeight,
                    uint256 previousInvariant,
                    uint256 currentInvariant,
                    uint256 protocolSwapFeePercentage
                ) internal pure returns (uint256) {
                    /*********************************************************************************
                    /*  protocolSwapFeePercentage * balanceToken * ( 1 - (previousInvariant / currentInvariant) ^ (1 / weightToken))
                    *********************************************************************************/
                    if (currentInvariant <= previousInvariant) {
                        // This shouldn't happen outside of rounding errors, but have this safeguard nonetheless to prevent the Pool
                        // from entering a locked state in which joins and exits revert while computing accumulated swap fees.
                        return 0;
                    }
                    // We round down to prevent issues in the Pool's accounting, even if it means paying slightly less in protocol
                    // fees to the Vault.
                    // Fee percentage and balance multiplications round down, while the subtrahend (power) rounds up (as does the
                    // base). Because previousInvariant / currentInvariant <= 1, the exponent rounds down.
                    uint256 base = previousInvariant.divUp(currentInvariant);
                    uint256 exponent = FixedPoint.ONE.divDown(normalizedWeight);
                    // Because the exponent is larger than one, the base of the power function has a lower bound. We cap to this
                    // value to avoid numeric issues, which means in the extreme case (where the invariant growth is larger than
                    // 1 / min exponent) the Pool will pay less in protocol fees than it should.
                    base = Math.max(base, FixedPoint.MIN_POW_BASE_FREE_EXPONENT);
                    uint256 power = base.powUp(exponent);
                    uint256 tokenAccruedFees = balance.mulDown(power.complement());
                    return tokenAccruedFees.mulDown(protocolSwapFeePercentage);
                }
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/IERC20.sol";
            import "./BaseWeightedPool.sol";
            library WeightedPoolUserDataHelpers {
                function joinKind(bytes memory self) internal pure returns (BaseWeightedPool.JoinKind) {
                    return abi.decode(self, (BaseWeightedPool.JoinKind));
                }
                function exitKind(bytes memory self) internal pure returns (BaseWeightedPool.ExitKind) {
                    return abi.decode(self, (BaseWeightedPool.ExitKind));
                }
                // Joins
                function initialAmountsIn(bytes memory self) internal pure returns (uint256[] memory amountsIn) {
                    (, amountsIn) = abi.decode(self, (BaseWeightedPool.JoinKind, uint256[]));
                }
                function exactTokensInForBptOut(bytes memory self)
                    internal
                    pure
                    returns (uint256[] memory amountsIn, uint256 minBPTAmountOut)
                {
                    (, amountsIn, minBPTAmountOut) = abi.decode(self, (BaseWeightedPool.JoinKind, uint256[], uint256));
                }
                function tokenInForExactBptOut(bytes memory self) internal pure returns (uint256 bptAmountOut, uint256 tokenIndex) {
                    (, bptAmountOut, tokenIndex) = abi.decode(self, (BaseWeightedPool.JoinKind, uint256, uint256));
                }
                // Exits
                function exactBptInForTokenOut(bytes memory self) internal pure returns (uint256 bptAmountIn, uint256 tokenIndex) {
                    (, bptAmountIn, tokenIndex) = abi.decode(self, (BaseWeightedPool.ExitKind, uint256, uint256));
                }
                function exactBptInForTokensOut(bytes memory self) internal pure returns (uint256 bptAmountIn) {
                    (, bptAmountIn) = abi.decode(self, (BaseWeightedPool.ExitKind, uint256));
                }
                function bptInForExactTokensOut(bytes memory self)
                    internal
                    pure
                    returns (uint256[] memory amountsOut, uint256 maxBPTAmountIn)
                {
                    (, amountsOut, maxBPTAmountIn) = abi.decode(self, (BaseWeightedPool.ExitKind, uint256[], uint256));
                }
            }
            // SPDX-License-Identifier: MIT
            // Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated
            // documentation files (the “Software”), to deal in the Software without restriction, including without limitation the
            // rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
            // permit persons to whom the Software is furnished to do so, subject to the following conditions:
            // The above copyright notice and this permission notice shall be included in all copies or substantial portions of the
            // Software.
            // THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
            // WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
            // COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
            // OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
            pragma solidity ^0.7.0;
            import "../helpers/BalancerErrors.sol";
            /* solhint-disable */
            /**
             * @dev Exponentiation and logarithm functions for 18 decimal fixed point numbers (both base and exponent/argument).
             *
             * Exponentiation and logarithm with arbitrary bases (x^y and log_x(y)) are implemented by conversion to natural
             * exponentiation and logarithm (where the base is Euler's number).
             *
             * @author Fernando Martinelli - @fernandomartinelli
             * @author Sergio Yuhjtman - @sergioyuhjtman
             * @author Daniel Fernandez - @dmf7z
             */
            library LogExpMath {
                // All fixed point multiplications and divisions are inlined. This means we need to divide by ONE when multiplying
                // two numbers, and multiply by ONE when dividing them.
                // All arguments and return values are 18 decimal fixed point numbers.
                int256 constant ONE_18 = 1e18;
                // Internally, intermediate values are computed with higher precision as 20 decimal fixed point numbers, and in the
                // case of ln36, 36 decimals.
                int256 constant ONE_20 = 1e20;
                int256 constant ONE_36 = 1e36;
                // The domain of natural exponentiation is bound by the word size and number of decimals used.
                //
                // Because internally the result will be stored using 20 decimals, the largest possible result is
                // (2^255 - 1) / 10^20, which makes the largest exponent ln((2^255 - 1) / 10^20) = 130.700829182905140221.
                // The smallest possible result is 10^(-18), which makes largest negative argument
                // ln(10^(-18)) = -41.446531673892822312.
                // We use 130.0 and -41.0 to have some safety margin.
                int256 constant MAX_NATURAL_EXPONENT = 130e18;
                int256 constant MIN_NATURAL_EXPONENT = -41e18;
                // Bounds for ln_36's argument. Both ln(0.9) and ln(1.1) can be represented with 36 decimal places in a fixed point
                // 256 bit integer.
                int256 constant LN_36_LOWER_BOUND = ONE_18 - 1e17;
                int256 constant LN_36_UPPER_BOUND = ONE_18 + 1e17;
                uint256 constant MILD_EXPONENT_BOUND = 2**254 / uint256(ONE_20);
                // 18 decimal constants
                int256 constant x0 = 128000000000000000000; // 2ˆ7
                int256 constant a0 = 38877084059945950922200000000000000000000000000000000000; // eˆ(x0) (no decimals)
                int256 constant x1 = 64000000000000000000; // 2ˆ6
                int256 constant a1 = 6235149080811616882910000000; // eˆ(x1) (no decimals)
                // 20 decimal constants
                int256 constant x2 = 3200000000000000000000; // 2ˆ5
                int256 constant a2 = 7896296018268069516100000000000000; // eˆ(x2)
                int256 constant x3 = 1600000000000000000000; // 2ˆ4
                int256 constant a3 = 888611052050787263676000000; // eˆ(x3)
                int256 constant x4 = 800000000000000000000; // 2ˆ3
                int256 constant a4 = 298095798704172827474000; // eˆ(x4)
                int256 constant x5 = 400000000000000000000; // 2ˆ2
                int256 constant a5 = 5459815003314423907810; // eˆ(x5)
                int256 constant x6 = 200000000000000000000; // 2ˆ1
                int256 constant a6 = 738905609893065022723; // eˆ(x6)
                int256 constant x7 = 100000000000000000000; // 2ˆ0
                int256 constant a7 = 271828182845904523536; // eˆ(x7)
                int256 constant x8 = 50000000000000000000; // 2ˆ-1
                int256 constant a8 = 164872127070012814685; // eˆ(x8)
                int256 constant x9 = 25000000000000000000; // 2ˆ-2
                int256 constant a9 = 128402541668774148407; // eˆ(x9)
                int256 constant x10 = 12500000000000000000; // 2ˆ-3
                int256 constant a10 = 113314845306682631683; // eˆ(x10)
                int256 constant x11 = 6250000000000000000; // 2ˆ-4
                int256 constant a11 = 106449445891785942956; // eˆ(x11)
                /**
                 * @dev Exponentiation (x^y) with unsigned 18 decimal fixed point base and exponent.
                 *
                 * Reverts if ln(x) * y is smaller than `MIN_NATURAL_EXPONENT`, or larger than `MAX_NATURAL_EXPONENT`.
                 */
                function pow(uint256 x, uint256 y) internal pure returns (uint256) {
                    if (y == 0) {
                        // We solve the 0^0 indetermination by making it equal one.
                        return uint256(ONE_18);
                    }
                    if (x == 0) {
                        return 0;
                    }
                    // Instead of computing x^y directly, we instead rely on the properties of logarithms and exponentiation to
                    // arrive at that result. In particular, exp(ln(x)) = x, and ln(x^y) = y * ln(x). This means
                    // x^y = exp(y * ln(x)).
                    // The ln function takes a signed value, so we need to make sure x fits in the signed 256 bit range.
                    _require(x < 2**255, Errors.X_OUT_OF_BOUNDS);
                    int256 x_int256 = int256(x);
                    // We will compute y * ln(x) in a single step. Depending on the value of x, we can either use ln or ln_36. In
                    // both cases, we leave the division by ONE_18 (due to fixed point multiplication) to the end.
                    // This prevents y * ln(x) from overflowing, and at the same time guarantees y fits in the signed 256 bit range.
                    _require(y < MILD_EXPONENT_BOUND, Errors.Y_OUT_OF_BOUNDS);
                    int256 y_int256 = int256(y);
                    int256 logx_times_y;
                    if (LN_36_LOWER_BOUND < x_int256 && x_int256 < LN_36_UPPER_BOUND) {
                        int256 ln_36_x = _ln_36(x_int256);
                        // ln_36_x has 36 decimal places, so multiplying by y_int256 isn't as straightforward, since we can't just
                        // bring y_int256 to 36 decimal places, as it might overflow. Instead, we perform two 18 decimal
                        // multiplications and add the results: one with the first 18 decimals of ln_36_x, and one with the
                        // (downscaled) last 18 decimals.
                        logx_times_y = ((ln_36_x / ONE_18) * y_int256 + ((ln_36_x % ONE_18) * y_int256) / ONE_18);
                    } else {
                        logx_times_y = _ln(x_int256) * y_int256;
                    }
                    logx_times_y /= ONE_18;
                    // Finally, we compute exp(y * ln(x)) to arrive at x^y
                    _require(
                        MIN_NATURAL_EXPONENT <= logx_times_y && logx_times_y <= MAX_NATURAL_EXPONENT,
                        Errors.PRODUCT_OUT_OF_BOUNDS
                    );
                    return uint256(exp(logx_times_y));
                }
                /**
                 * @dev Natural exponentiation (e^x) with signed 18 decimal fixed point exponent.
                 *
                 * Reverts if `x` is smaller than MIN_NATURAL_EXPONENT, or larger than `MAX_NATURAL_EXPONENT`.
                 */
                function exp(int256 x) internal pure returns (int256) {
                    _require(x >= MIN_NATURAL_EXPONENT && x <= MAX_NATURAL_EXPONENT, Errors.INVALID_EXPONENT);
                    if (x < 0) {
                        // We only handle positive exponents: e^(-x) is computed as 1 / e^x. We can safely make x positive since it
                        // fits in the signed 256 bit range (as it is larger than MIN_NATURAL_EXPONENT).
                        // Fixed point division requires multiplying by ONE_18.
                        return ((ONE_18 * ONE_18) / exp(-x));
                    }
                    // First, we use the fact that e^(x+y) = e^x * e^y to decompose x into a sum of powers of two, which we call x_n,
                    // where x_n == 2^(7 - n), and e^x_n = a_n has been precomputed. We choose the first x_n, x0, to equal 2^7
                    // because all larger powers are larger than MAX_NATURAL_EXPONENT, and therefore not present in the
                    // decomposition.
                    // At the end of this process we will have the product of all e^x_n = a_n that apply, and the remainder of this
                    // decomposition, which will be lower than the smallest x_n.
                    // exp(x) = k_0 * a_0 * k_1 * a_1 * ... + k_n * a_n * exp(remainder), where each k_n equals either 0 or 1.
                    // We mutate x by subtracting x_n, making it the remainder of the decomposition.
                    // The first two a_n (e^(2^7) and e^(2^6)) are too large if stored as 18 decimal numbers, and could cause
                    // intermediate overflows. Instead we store them as plain integers, with 0 decimals.
                    // Additionally, x0 + x1 is larger than MAX_NATURAL_EXPONENT, which means they will not both be present in the
                    // decomposition.
                    // For each x_n, we test if that term is present in the decomposition (if x is larger than it), and if so deduct
                    // it and compute the accumulated product.
                    int256 firstAN;
                    if (x >= x0) {
                        x -= x0;
                        firstAN = a0;
                    } else if (x >= x1) {
                        x -= x1;
                        firstAN = a1;
                    } else {
                        firstAN = 1; // One with no decimal places
                    }
                    // We now transform x into a 20 decimal fixed point number, to have enhanced precision when computing the
                    // smaller terms.
                    x *= 100;
                    // `product` is the accumulated product of all a_n (except a0 and a1), which starts at 20 decimal fixed point
                    // one. Recall that fixed point multiplication requires dividing by ONE_20.
                    int256 product = ONE_20;
                    if (x >= x2) {
                        x -= x2;
                        product = (product * a2) / ONE_20;
                    }
                    if (x >= x3) {
                        x -= x3;
                        product = (product * a3) / ONE_20;
                    }
                    if (x >= x4) {
                        x -= x4;
                        product = (product * a4) / ONE_20;
                    }
                    if (x >= x5) {
                        x -= x5;
                        product = (product * a5) / ONE_20;
                    }
                    if (x >= x6) {
                        x -= x6;
                        product = (product * a6) / ONE_20;
                    }
                    if (x >= x7) {
                        x -= x7;
                        product = (product * a7) / ONE_20;
                    }
                    if (x >= x8) {
                        x -= x8;
                        product = (product * a8) / ONE_20;
                    }
                    if (x >= x9) {
                        x -= x9;
                        product = (product * a9) / ONE_20;
                    }
                    // x10 and x11 are unnecessary here since we have high enough precision already.
                    // Now we need to compute e^x, where x is small (in particular, it is smaller than x9). We use the Taylor series
                    // expansion for e^x: 1 + x + (x^2 / 2!) + (x^3 / 3!) + ... + (x^n / n!).
                    int256 seriesSum = ONE_20; // The initial one in the sum, with 20 decimal places.
                    int256 term; // Each term in the sum, where the nth term is (x^n / n!).
                    // The first term is simply x.
                    term = x;
                    seriesSum += term;
                    // Each term (x^n / n!) equals the previous one times x, divided by n. Since x is a fixed point number,
                    // multiplying by it requires dividing by ONE_20, but dividing by the non-fixed point n values does not.
                    term = ((term * x) / ONE_20) / 2;
                    seriesSum += term;
                    term = ((term * x) / ONE_20) / 3;
                    seriesSum += term;
                    term = ((term * x) / ONE_20) / 4;
                    seriesSum += term;
                    term = ((term * x) / ONE_20) / 5;
                    seriesSum += term;
                    term = ((term * x) / ONE_20) / 6;
                    seriesSum += term;
                    term = ((term * x) / ONE_20) / 7;
                    seriesSum += term;
                    term = ((term * x) / ONE_20) / 8;
                    seriesSum += term;
                    term = ((term * x) / ONE_20) / 9;
                    seriesSum += term;
                    term = ((term * x) / ONE_20) / 10;
                    seriesSum += term;
                    term = ((term * x) / ONE_20) / 11;
                    seriesSum += term;
                    term = ((term * x) / ONE_20) / 12;
                    seriesSum += term;
                    // 12 Taylor terms are sufficient for 18 decimal precision.
                    // We now have the first a_n (with no decimals), and the product of all other a_n present, and the Taylor
                    // approximation of the exponentiation of the remainder (both with 20 decimals). All that remains is to multiply
                    // all three (one 20 decimal fixed point multiplication, dividing by ONE_20, and one integer multiplication),
                    // and then drop two digits to return an 18 decimal value.
                    return (((product * seriesSum) / ONE_20) * firstAN) / 100;
                }
                /**
                 * @dev Logarithm (log(arg, base), with signed 18 decimal fixed point base and argument.
                 */
                function log(int256 arg, int256 base) internal pure returns (int256) {
                    // This performs a simple base change: log(arg, base) = ln(arg) / ln(base).
                    // Both logBase and logArg are computed as 36 decimal fixed point numbers, either by using ln_36, or by
                    // upscaling.
                    int256 logBase;
                    if (LN_36_LOWER_BOUND < base && base < LN_36_UPPER_BOUND) {
                        logBase = _ln_36(base);
                    } else {
                        logBase = _ln(base) * ONE_18;
                    }
                    int256 logArg;
                    if (LN_36_LOWER_BOUND < arg && arg < LN_36_UPPER_BOUND) {
                        logArg = _ln_36(arg);
                    } else {
                        logArg = _ln(arg) * ONE_18;
                    }
                    // When dividing, we multiply by ONE_18 to arrive at a result with 18 decimal places
                    return (logArg * ONE_18) / logBase;
                }
                /**
                 * @dev Natural logarithm (ln(a)) with signed 18 decimal fixed point argument.
                 */
                function ln(int256 a) internal pure returns (int256) {
                    // The real natural logarithm is not defined for negative numbers or zero.
                    _require(a > 0, Errors.OUT_OF_BOUNDS);
                    if (LN_36_LOWER_BOUND < a && a < LN_36_UPPER_BOUND) {
                        return _ln_36(a) / ONE_18;
                    } else {
                        return _ln(a);
                    }
                }
                /**
                 * @dev Internal natural logarithm (ln(a)) with signed 18 decimal fixed point argument.
                 */
                function _ln(int256 a) private pure returns (int256) {
                    if (a < ONE_18) {
                        // Since ln(a^k) = k * ln(a), we can compute ln(a) as ln(a) = ln((1/a)^(-1)) = - ln((1/a)). If a is less
                        // than one, 1/a will be greater than one, and this if statement will not be entered in the recursive call.
                        // Fixed point division requires multiplying by ONE_18.
                        return (-_ln((ONE_18 * ONE_18) / a));
                    }
                    // First, we use the fact that ln^(a * b) = ln(a) + ln(b) to decompose ln(a) into a sum of powers of two, which
                    // we call x_n, where x_n == 2^(7 - n), which are the natural logarithm of precomputed quantities a_n (that is,
                    // ln(a_n) = x_n). We choose the first x_n, x0, to equal 2^7 because the exponential of all larger powers cannot
                    // be represented as 18 fixed point decimal numbers in 256 bits, and are therefore larger than a.
                    // At the end of this process we will have the sum of all x_n = ln(a_n) that apply, and the remainder of this
                    // decomposition, which will be lower than the smallest a_n.
                    // ln(a) = k_0 * x_0 + k_1 * x_1 + ... + k_n * x_n + ln(remainder), where each k_n equals either 0 or 1.
                    // We mutate a by subtracting a_n, making it the remainder of the decomposition.
                    // For reasons related to how `exp` works, the first two a_n (e^(2^7) and e^(2^6)) are not stored as fixed point
                    // numbers with 18 decimals, but instead as plain integers with 0 decimals, so we need to multiply them by
                    // ONE_18 to convert them to fixed point.
                    // For each a_n, we test if that term is present in the decomposition (if a is larger than it), and if so divide
                    // by it and compute the accumulated sum.
                    int256 sum = 0;
                    if (a >= a0 * ONE_18) {
                        a /= a0; // Integer, not fixed point division
                        sum += x0;
                    }
                    if (a >= a1 * ONE_18) {
                        a /= a1; // Integer, not fixed point division
                        sum += x1;
                    }
                    // All other a_n and x_n are stored as 20 digit fixed point numbers, so we convert the sum and a to this format.
                    sum *= 100;
                    a *= 100;
                    // Because further a_n are  20 digit fixed point numbers, we multiply by ONE_20 when dividing by them.
                    if (a >= a2) {
                        a = (a * ONE_20) / a2;
                        sum += x2;
                    }
                    if (a >= a3) {
                        a = (a * ONE_20) / a3;
                        sum += x3;
                    }
                    if (a >= a4) {
                        a = (a * ONE_20) / a4;
                        sum += x4;
                    }
                    if (a >= a5) {
                        a = (a * ONE_20) / a5;
                        sum += x5;
                    }
                    if (a >= a6) {
                        a = (a * ONE_20) / a6;
                        sum += x6;
                    }
                    if (a >= a7) {
                        a = (a * ONE_20) / a7;
                        sum += x7;
                    }
                    if (a >= a8) {
                        a = (a * ONE_20) / a8;
                        sum += x8;
                    }
                    if (a >= a9) {
                        a = (a * ONE_20) / a9;
                        sum += x9;
                    }
                    if (a >= a10) {
                        a = (a * ONE_20) / a10;
                        sum += x10;
                    }
                    if (a >= a11) {
                        a = (a * ONE_20) / a11;
                        sum += x11;
                    }
                    // a is now a small number (smaller than a_11, which roughly equals 1.06). This means we can use a Taylor series
                    // that converges rapidly for values of `a` close to one - the same one used in ln_36.
                    // Let z = (a - 1) / (a + 1).
                    // ln(a) = 2 * (z + z^3 / 3 + z^5 / 5 + z^7 / 7 + ... + z^(2 * n + 1) / (2 * n + 1))
                    // Recall that 20 digit fixed point division requires multiplying by ONE_20, and multiplication requires
                    // division by ONE_20.
                    int256 z = ((a - ONE_20) * ONE_20) / (a + ONE_20);
                    int256 z_squared = (z * z) / ONE_20;
                    // num is the numerator of the series: the z^(2 * n + 1) term
                    int256 num = z;
                    // seriesSum holds the accumulated sum of each term in the series, starting with the initial z
                    int256 seriesSum = num;
                    // In each step, the numerator is multiplied by z^2
                    num = (num * z_squared) / ONE_20;
                    seriesSum += num / 3;
                    num = (num * z_squared) / ONE_20;
                    seriesSum += num / 5;
                    num = (num * z_squared) / ONE_20;
                    seriesSum += num / 7;
                    num = (num * z_squared) / ONE_20;
                    seriesSum += num / 9;
                    num = (num * z_squared) / ONE_20;
                    seriesSum += num / 11;
                    // 6 Taylor terms are sufficient for 36 decimal precision.
                    // Finally, we multiply by 2 (non fixed point) to compute ln(remainder)
                    seriesSum *= 2;
                    // We now have the sum of all x_n present, and the Taylor approximation of the logarithm of the remainder (both
                    // with 20 decimals). All that remains is to sum these two, and then drop two digits to return a 18 decimal
                    // value.
                    return (sum + seriesSum) / 100;
                }
                /**
                 * @dev Intrnal high precision (36 decimal places) natural logarithm (ln(x)) with signed 18 decimal fixed point argument,
                 * for x close to one.
                 *
                 * Should only be used if x is between LN_36_LOWER_BOUND and LN_36_UPPER_BOUND.
                 */
                function _ln_36(int256 x) private pure returns (int256) {
                    // Since ln(1) = 0, a value of x close to one will yield a very small result, which makes using 36 digits
                    // worthwhile.
                    // First, we transform x to a 36 digit fixed point value.
                    x *= ONE_18;
                    // We will use the following Taylor expansion, which converges very rapidly. Let z = (x - 1) / (x + 1).
                    // ln(x) = 2 * (z + z^3 / 3 + z^5 / 5 + z^7 / 7 + ... + z^(2 * n + 1) / (2 * n + 1))
                    // Recall that 36 digit fixed point division requires multiplying by ONE_36, and multiplication requires
                    // division by ONE_36.
                    int256 z = ((x - ONE_36) * ONE_36) / (x + ONE_36);
                    int256 z_squared = (z * z) / ONE_36;
                    // num is the numerator of the series: the z^(2 * n + 1) term
                    int256 num = z;
                    // seriesSum holds the accumulated sum of each term in the series, starting with the initial z
                    int256 seriesSum = num;
                    // In each step, the numerator is multiplied by z^2
                    num = (num * z_squared) / ONE_36;
                    seriesSum += num / 3;
                    num = (num * z_squared) / ONE_36;
                    seriesSum += num / 5;
                    num = (num * z_squared) / ONE_36;
                    seriesSum += num / 7;
                    num = (num * z_squared) / ONE_36;
                    seriesSum += num / 9;
                    num = (num * z_squared) / ONE_36;
                    seriesSum += num / 11;
                    num = (num * z_squared) / ONE_36;
                    seriesSum += num / 13;
                    num = (num * z_squared) / ONE_36;
                    seriesSum += num / 15;
                    // 8 Taylor terms are sufficient for 36 decimal precision.
                    // All that remains is multiplying by 2 (non fixed point).
                    return seriesSum * 2;
                }
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            // solhint-disable
            /**
             * @dev Reverts if `condition` is false, with a revert reason containing `errorCode`. Only codes up to 999 are
             * supported.
             */
            function _require(bool condition, uint256 errorCode) pure {
                if (!condition) _revert(errorCode);
            }
            /**
             * @dev Reverts with a revert reason containing `errorCode`. Only codes up to 999 are supported.
             */
            function _revert(uint256 errorCode) pure {
                // We're going to dynamically create a revert string based on the error code, with the following format:
                // 'BAL#{errorCode}'
                // where the code is left-padded with zeroes to three digits (so they range from 000 to 999).
                //
                // We don't have revert strings embedded in the contract to save bytecode size: it takes much less space to store a
                // number (8 to 16 bits) than the individual string characters.
                //
                // The dynamic string creation algorithm that follows could be implemented in Solidity, but assembly allows for a
                // much denser implementation, again saving bytecode size. Given this function unconditionally reverts, this is a
                // safe place to rely on it without worrying about how its usage might affect e.g. memory contents.
                assembly {
                    // First, we need to compute the ASCII representation of the error code. We assume that it is in the 0-999
                    // range, so we only need to convert three digits. To convert the digits to ASCII, we add 0x30, the value for
                    // the '0' character.
                    let units := add(mod(errorCode, 10), 0x30)
                    errorCode := div(errorCode, 10)
                    let tenths := add(mod(errorCode, 10), 0x30)
                    errorCode := div(errorCode, 10)
                    let hundreds := add(mod(errorCode, 10), 0x30)
                    // With the individual characters, we can now construct the full string. The "BAL#" part is a known constant
                    // (0x42414c23): we simply shift this by 24 (to provide space for the 3 bytes of the error code), and add the
                    // characters to it, each shifted by a multiple of 8.
                    // The revert reason is then shifted left by 200 bits (256 minus the length of the string, 7 characters * 8 bits
                    // per character = 56) to locate it in the most significant part of the 256 slot (the beginning of a byte
                    // array).
                    let revertReason := shl(200, add(0x42414c23000000, add(add(units, shl(8, tenths)), shl(16, hundreds))))
                    // We can now encode the reason in memory, which can be safely overwritten as we're about to revert. The encoded
                    // message will have the following layout:
                    // [ revert reason identifier ] [ string location offset ] [ string length ] [ string contents ]
                    // The Solidity revert reason identifier is 0x08c739a0, the function selector of the Error(string) function. We
                    // also write zeroes to the next 28 bytes of memory, but those are about to be overwritten.
                    mstore(0x0, 0x08c379a000000000000000000000000000000000000000000000000000000000)
                    // Next is the offset to the location of the string, which will be placed immediately after (20 bytes away).
                    mstore(0x04, 0x0000000000000000000000000000000000000000000000000000000000000020)
                    // The string length is fixed: 7 characters.
                    mstore(0x24, 7)
                    // Finally, the string itself is stored.
                    mstore(0x44, revertReason)
                    // Even if the string is only 7 bytes long, we need to return a full 32 byte slot containing it. The length of
                    // the encoded message is therefore 4 + 32 + 32 + 32 = 100.
                    revert(0, 100)
                }
            }
            library Errors {
                // Math
                uint256 internal constant ADD_OVERFLOW = 0;
                uint256 internal constant SUB_OVERFLOW = 1;
                uint256 internal constant SUB_UNDERFLOW = 2;
                uint256 internal constant MUL_OVERFLOW = 3;
                uint256 internal constant ZERO_DIVISION = 4;
                uint256 internal constant DIV_INTERNAL = 5;
                uint256 internal constant X_OUT_OF_BOUNDS = 6;
                uint256 internal constant Y_OUT_OF_BOUNDS = 7;
                uint256 internal constant PRODUCT_OUT_OF_BOUNDS = 8;
                uint256 internal constant INVALID_EXPONENT = 9;
                // Input
                uint256 internal constant OUT_OF_BOUNDS = 100;
                uint256 internal constant UNSORTED_ARRAY = 101;
                uint256 internal constant UNSORTED_TOKENS = 102;
                uint256 internal constant INPUT_LENGTH_MISMATCH = 103;
                uint256 internal constant ZERO_TOKEN = 104;
                // Shared pools
                uint256 internal constant MIN_TOKENS = 200;
                uint256 internal constant MAX_TOKENS = 201;
                uint256 internal constant MAX_SWAP_FEE_PERCENTAGE = 202;
                uint256 internal constant MIN_SWAP_FEE_PERCENTAGE = 203;
                uint256 internal constant MINIMUM_BPT = 204;
                uint256 internal constant CALLER_NOT_VAULT = 205;
                uint256 internal constant UNINITIALIZED = 206;
                uint256 internal constant BPT_IN_MAX_AMOUNT = 207;
                uint256 internal constant BPT_OUT_MIN_AMOUNT = 208;
                uint256 internal constant EXPIRED_PERMIT = 209;
                uint256 internal constant NOT_TWO_TOKENS = 210;
                uint256 internal constant DISABLED = 211;
                // Pools
                uint256 internal constant MIN_AMP = 300;
                uint256 internal constant MAX_AMP = 301;
                uint256 internal constant MIN_WEIGHT = 302;
                uint256 internal constant MAX_STABLE_TOKENS = 303;
                uint256 internal constant MAX_IN_RATIO = 304;
                uint256 internal constant MAX_OUT_RATIO = 305;
                uint256 internal constant MIN_BPT_IN_FOR_TOKEN_OUT = 306;
                uint256 internal constant MAX_OUT_BPT_FOR_TOKEN_IN = 307;
                uint256 internal constant NORMALIZED_WEIGHT_INVARIANT = 308;
                uint256 internal constant INVALID_TOKEN = 309;
                uint256 internal constant UNHANDLED_JOIN_KIND = 310;
                uint256 internal constant ZERO_INVARIANT = 311;
                uint256 internal constant ORACLE_INVALID_SECONDS_QUERY = 312;
                uint256 internal constant ORACLE_NOT_INITIALIZED = 313;
                uint256 internal constant ORACLE_QUERY_TOO_OLD = 314;
                uint256 internal constant ORACLE_INVALID_INDEX = 315;
                uint256 internal constant ORACLE_BAD_SECS = 316;
                uint256 internal constant AMP_END_TIME_TOO_CLOSE = 317;
                uint256 internal constant AMP_ONGOING_UPDATE = 318;
                uint256 internal constant AMP_RATE_TOO_HIGH = 319;
                uint256 internal constant AMP_NO_ONGOING_UPDATE = 320;
                uint256 internal constant STABLE_INVARIANT_DIDNT_CONVERGE = 321;
                uint256 internal constant STABLE_GET_BALANCE_DIDNT_CONVERGE = 322;
                uint256 internal constant RELAYER_NOT_CONTRACT = 323;
                uint256 internal constant BASE_POOL_RELAYER_NOT_CALLED = 324;
                uint256 internal constant REBALANCING_RELAYER_REENTERED = 325;
                uint256 internal constant GRADUAL_UPDATE_TIME_TRAVEL = 326;
                uint256 internal constant SWAPS_DISABLED = 327;
                uint256 internal constant CALLER_IS_NOT_LBP_OWNER = 328;
                uint256 internal constant PRICE_RATE_OVERFLOW = 329;
                // Lib
                uint256 internal constant REENTRANCY = 400;
                uint256 internal constant SENDER_NOT_ALLOWED = 401;
                uint256 internal constant PAUSED = 402;
                uint256 internal constant PAUSE_WINDOW_EXPIRED = 403;
                uint256 internal constant MAX_PAUSE_WINDOW_DURATION = 404;
                uint256 internal constant MAX_BUFFER_PERIOD_DURATION = 405;
                uint256 internal constant INSUFFICIENT_BALANCE = 406;
                uint256 internal constant INSUFFICIENT_ALLOWANCE = 407;
                uint256 internal constant ERC20_TRANSFER_FROM_ZERO_ADDRESS = 408;
                uint256 internal constant ERC20_TRANSFER_TO_ZERO_ADDRESS = 409;
                uint256 internal constant ERC20_MINT_TO_ZERO_ADDRESS = 410;
                uint256 internal constant ERC20_BURN_FROM_ZERO_ADDRESS = 411;
                uint256 internal constant ERC20_APPROVE_FROM_ZERO_ADDRESS = 412;
                uint256 internal constant ERC20_APPROVE_TO_ZERO_ADDRESS = 413;
                uint256 internal constant ERC20_TRANSFER_EXCEEDS_ALLOWANCE = 414;
                uint256 internal constant ERC20_DECREASED_ALLOWANCE_BELOW_ZERO = 415;
                uint256 internal constant ERC20_TRANSFER_EXCEEDS_BALANCE = 416;
                uint256 internal constant ERC20_BURN_EXCEEDS_ALLOWANCE = 417;
                uint256 internal constant SAFE_ERC20_CALL_FAILED = 418;
                uint256 internal constant ADDRESS_INSUFFICIENT_BALANCE = 419;
                uint256 internal constant ADDRESS_CANNOT_SEND_VALUE = 420;
                uint256 internal constant SAFE_CAST_VALUE_CANT_FIT_INT256 = 421;
                uint256 internal constant GRANT_SENDER_NOT_ADMIN = 422;
                uint256 internal constant REVOKE_SENDER_NOT_ADMIN = 423;
                uint256 internal constant RENOUNCE_SENDER_NOT_ALLOWED = 424;
                uint256 internal constant BUFFER_PERIOD_EXPIRED = 425;
                uint256 internal constant CALLER_IS_NOT_OWNER = 426;
                uint256 internal constant NEW_OWNER_IS_ZERO = 427;
                uint256 internal constant CODE_DEPLOYMENT_FAILED = 428;
                uint256 internal constant CALL_TO_NON_CONTRACT = 429;
                uint256 internal constant LOW_LEVEL_CALL_FAILED = 430;
                // Vault
                uint256 internal constant INVALID_POOL_ID = 500;
                uint256 internal constant CALLER_NOT_POOL = 501;
                uint256 internal constant SENDER_NOT_ASSET_MANAGER = 502;
                uint256 internal constant USER_DOESNT_ALLOW_RELAYER = 503;
                uint256 internal constant INVALID_SIGNATURE = 504;
                uint256 internal constant EXIT_BELOW_MIN = 505;
                uint256 internal constant JOIN_ABOVE_MAX = 506;
                uint256 internal constant SWAP_LIMIT = 507;
                uint256 internal constant SWAP_DEADLINE = 508;
                uint256 internal constant CANNOT_SWAP_SAME_TOKEN = 509;
                uint256 internal constant UNKNOWN_AMOUNT_IN_FIRST_SWAP = 510;
                uint256 internal constant MALCONSTRUCTED_MULTIHOP_SWAP = 511;
                uint256 internal constant INTERNAL_BALANCE_OVERFLOW = 512;
                uint256 internal constant INSUFFICIENT_INTERNAL_BALANCE = 513;
                uint256 internal constant INVALID_ETH_INTERNAL_BALANCE = 514;
                uint256 internal constant INVALID_POST_LOAN_BALANCE = 515;
                uint256 internal constant INSUFFICIENT_ETH = 516;
                uint256 internal constant UNALLOCATED_ETH = 517;
                uint256 internal constant ETH_TRANSFER = 518;
                uint256 internal constant CANNOT_USE_ETH_SENTINEL = 519;
                uint256 internal constant TOKENS_MISMATCH = 520;
                uint256 internal constant TOKEN_NOT_REGISTERED = 521;
                uint256 internal constant TOKEN_ALREADY_REGISTERED = 522;
                uint256 internal constant TOKENS_ALREADY_SET = 523;
                uint256 internal constant TOKENS_LENGTH_MUST_BE_2 = 524;
                uint256 internal constant NONZERO_TOKEN_BALANCE = 525;
                uint256 internal constant BALANCE_TOTAL_OVERFLOW = 526;
                uint256 internal constant POOL_NO_TOKENS = 527;
                uint256 internal constant INSUFFICIENT_FLASH_LOAN_BALANCE = 528;
                // Fees
                uint256 internal constant SWAP_FEE_PERCENTAGE_TOO_HIGH = 600;
                uint256 internal constant FLASH_LOAN_FEE_PERCENTAGE_TOO_HIGH = 601;
                uint256 internal constant INSUFFICIENT_FLASH_LOAN_FEE_AMOUNT = 602;
            }
            // SPDX-License-Identifier: MIT
            pragma solidity ^0.7.0;
            /**
             * @dev Interface of the ERC20 standard as defined in the EIP.
             */
            interface IERC20 {
                /**
                 * @dev Returns the amount of tokens in existence.
                 */
                function totalSupply() external view returns (uint256);
                /**
                 * @dev Returns the amount of tokens owned by `account`.
                 */
                function balanceOf(address account) external view returns (uint256);
                /**
                 * @dev Moves `amount` tokens from the caller's account to `recipient`.
                 *
                 * Returns a boolean value indicating whether the operation succeeded.
                 *
                 * Emits a {Transfer} event.
                 */
                function transfer(address recipient, uint256 amount) external returns (bool);
                /**
                 * @dev Returns the remaining number of tokens that `spender` will be
                 * allowed to spend on behalf of `owner` through {transferFrom}. This is
                 * zero by default.
                 *
                 * This value changes when {approve} or {transferFrom} are called.
                 */
                function allowance(address owner, address spender) external view returns (uint256);
                /**
                 * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
                 *
                 * Returns a boolean value indicating whether the operation succeeded.
                 *
                 * IMPORTANT: Beware that changing an allowance with this method brings the risk
                 * that someone may use both the old and the new allowance by unfortunate
                 * transaction ordering. One possible solution to mitigate this race
                 * condition is to first reduce the spender's allowance to 0 and set the
                 * desired value afterwards:
                 * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
                 *
                 * Emits an {Approval} event.
                 */
                function approve(address spender, uint256 amount) external returns (bool);
                /**
                 * @dev Moves `amount` tokens from `sender` to `recipient` using the
                 * allowance mechanism. `amount` is then deducted from the caller's
                 * allowance.
                 *
                 * Returns a boolean value indicating whether the operation succeeded.
                 *
                 * Emits a {Transfer} event.
                 */
                function transferFrom(
                    address sender,
                    address recipient,
                    uint256 amount
                ) external returns (bool);
                /**
                 * @dev Emitted when `value` tokens are moved from one account (`from`) to
                 * another (`to`).
                 *
                 * Note that `value` may be zero.
                 */
                event Transfer(address indexed from, address indexed to, uint256 value);
                /**
                 * @dev Emitted when the allowance of a `spender` for an `owner` is set by
                 * a call to {approve}. `value` is the new allowance.
                 */
                event Approval(address indexed owner, address indexed spender, uint256 value);
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            pragma experimental ABIEncoderV2;
            import "@balancer-labs/v2-solidity-utils/contracts/math/Math.sol";
            import "@balancer-labs/v2-solidity-utils/contracts/math/FixedPoint.sol";
            import "@balancer-labs/v2-solidity-utils/contracts/helpers/InputHelpers.sol";
            import "@balancer-labs/v2-solidity-utils/contracts/helpers/TemporarilyPausable.sol";
            import "@balancer-labs/v2-solidity-utils/contracts/helpers/WordCodec.sol";
            import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/ERC20.sol";
            import "@balancer-labs/v2-vault/contracts/interfaces/IVault.sol";
            import "@balancer-labs/v2-vault/contracts/interfaces/IBasePool.sol";
            import "@balancer-labs/v2-asset-manager-utils/contracts/IAssetManager.sol";
            import "./BalancerPoolToken.sol";
            import "./BasePoolAuthorization.sol";
            // solhint-disable max-states-count
            /**
             * @dev Reference implementation for the base layer of a Pool contract that manages a single Pool with optional
             * Asset Managers, an admin-controlled swap fee percentage, and an emergency pause mechanism.
             *
             * Note that neither swap fees nor the pause mechanism are used by this contract. They are passed through so that
             * derived contracts can use them via the `_addSwapFeeAmount` and `_subtractSwapFeeAmount` functions, and the
             * `whenNotPaused` modifier.
             *
             * No admin permissions are checked here: instead, this contract delegates that to the Vault's own Authorizer.
             *
             * Because this contract doesn't implement the swap hooks, derived contracts should generally inherit from
             * BaseGeneralPool or BaseMinimalSwapInfoPool. Otherwise, subclasses must inherit from the corresponding interfaces
             * and implement the swap callbacks themselves.
             */
            abstract contract BasePool is IBasePool, BasePoolAuthorization, BalancerPoolToken, TemporarilyPausable {
                using WordCodec for bytes32;
                using FixedPoint for uint256;
                uint256 private constant _MIN_TOKENS = 2;
                // 1e18 corresponds to 1.0, or a 100% fee
                uint256 private constant _MIN_SWAP_FEE_PERCENTAGE = 1e12; // 0.0001%
                uint256 private constant _MAX_SWAP_FEE_PERCENTAGE = 1e17; // 10%
                uint256 private constant _MINIMUM_BPT = 1e6;
                // Storage slot that can be used to store unrelated pieces of information. In particular, by default is used
                // to store only the swap fee percentage of a pool. But it can be extended to store some more pieces of information.
                // The swap fee percentage is stored in the most-significant 64 bits, therefore the remaining 192 bits can be
                // used to store any other piece of information.
                bytes32 private _miscData;
                uint256 private constant _SWAP_FEE_PERCENTAGE_OFFSET = 192;
                IVault private immutable _vault;
                bytes32 private immutable _poolId;
                event SwapFeePercentageChanged(uint256 swapFeePercentage);
                constructor(
                    IVault vault,
                    IVault.PoolSpecialization specialization,
                    string memory name,
                    string memory symbol,
                    IERC20[] memory tokens,
                    address[] memory assetManagers,
                    uint256 swapFeePercentage,
                    uint256 pauseWindowDuration,
                    uint256 bufferPeriodDuration,
                    address owner
                )
                    // Base Pools are expected to be deployed using factories. By using the factory address as the action
                    // disambiguator, we make all Pools deployed by the same factory share action identifiers. This allows for
                    // simpler management of permissions (such as being able to manage granting the 'set fee percentage' action in
                    // any Pool created by the same factory), while still making action identifiers unique among different factories
                    // if the selectors match, preventing accidental errors.
                    Authentication(bytes32(uint256(msg.sender)))
                    BalancerPoolToken(name, symbol)
                    BasePoolAuthorization(owner)
                    TemporarilyPausable(pauseWindowDuration, bufferPeriodDuration)
                {
                    _require(tokens.length >= _MIN_TOKENS, Errors.MIN_TOKENS);
                    _require(tokens.length <= _getMaxTokens(), Errors.MAX_TOKENS);
                    // The Vault only requires the token list to be ordered for the Two Token Pools specialization. However,
                    // to make the developer experience consistent, we are requiring this condition for all the native pools.
                    // Also, since these Pools will register tokens only once, we can ensure the Pool tokens will follow the same
                    // order. We rely on this property to make Pools simpler to write, as it lets us assume that the
                    // order of token-specific parameters (such as token weights) will not change.
                    InputHelpers.ensureArrayIsSorted(tokens);
                    _setSwapFeePercentage(swapFeePercentage);
                    bytes32 poolId = vault.registerPool(specialization);
                    vault.registerTokens(poolId, tokens, assetManagers);
                    // Set immutable state variables - these cannot be read from during construction
                    _vault = vault;
                    _poolId = poolId;
                }
                // Getters / Setters
                function getVault() public view returns (IVault) {
                    return _vault;
                }
                function getPoolId() public view override returns (bytes32) {
                    return _poolId;
                }
                function _getTotalTokens() internal view virtual returns (uint256);
                function _getMaxTokens() internal pure virtual returns (uint256);
                function getSwapFeePercentage() public view returns (uint256) {
                    return _miscData.decodeUint64(_SWAP_FEE_PERCENTAGE_OFFSET);
                }
                function setSwapFeePercentage(uint256 swapFeePercentage) external virtual authenticate whenNotPaused {
                    _setSwapFeePercentage(swapFeePercentage);
                }
                function _setSwapFeePercentage(uint256 swapFeePercentage) private {
                    _require(swapFeePercentage >= _MIN_SWAP_FEE_PERCENTAGE, Errors.MIN_SWAP_FEE_PERCENTAGE);
                    _require(swapFeePercentage <= _MAX_SWAP_FEE_PERCENTAGE, Errors.MAX_SWAP_FEE_PERCENTAGE);
                    _miscData = _miscData.insertUint64(swapFeePercentage, _SWAP_FEE_PERCENTAGE_OFFSET);
                    emit SwapFeePercentageChanged(swapFeePercentage);
                }
                function setAssetManagerPoolConfig(IERC20 token, bytes memory poolConfig)
                    public
                    virtual
                    authenticate
                    whenNotPaused
                {
                    _setAssetManagerPoolConfig(token, poolConfig);
                }
                function _setAssetManagerPoolConfig(IERC20 token, bytes memory poolConfig) private {
                    bytes32 poolId = getPoolId();
                    (, , , address assetManager) = getVault().getPoolTokenInfo(poolId, token);
                    IAssetManager(assetManager).setConfig(poolId, poolConfig);
                }
                function setPaused(bool paused) external authenticate {
                    _setPaused(paused);
                }
                function _isOwnerOnlyAction(bytes32 actionId) internal view virtual override returns (bool) {
                    return
                        (actionId == getActionId(this.setSwapFeePercentage.selector)) ||
                        (actionId == getActionId(this.setAssetManagerPoolConfig.selector));
                }
                function _getMiscData() internal view returns (bytes32) {
                    return _miscData;
                }
                /**
                 * Inserts data into the least-significant 192 bits of the misc data storage slot.
                 * Note that the remaining 64 bits are used for the swap fee percentage and cannot be overloaded.
                 */
                function _setMiscData(bytes32 newData) internal {
                    _miscData = _miscData.insertBits192(newData, 0);
                }
                // Join / Exit Hooks
                modifier onlyVault(bytes32 poolId) {
                    _require(msg.sender == address(getVault()), Errors.CALLER_NOT_VAULT);
                    _require(poolId == getPoolId(), Errors.INVALID_POOL_ID);
                    _;
                }
                function onJoinPool(
                    bytes32 poolId,
                    address sender,
                    address recipient,
                    uint256[] memory balances,
                    uint256 lastChangeBlock,
                    uint256 protocolSwapFeePercentage,
                    bytes memory userData
                ) public virtual override onlyVault(poolId) returns (uint256[] memory, uint256[] memory) {
                    uint256[] memory scalingFactors = _scalingFactors();
                    if (totalSupply() == 0) {
                        (uint256 bptAmountOut, uint256[] memory amountsIn) = _onInitializePool(
                            poolId,
                            sender,
                            recipient,
                            scalingFactors,
                            userData
                        );
                        // On initialization, we lock _MINIMUM_BPT by minting it for the zero address. This BPT acts as a minimum
                        // as it will never be burned, which reduces potential issues with rounding, and also prevents the Pool from
                        // ever being fully drained.
                        _require(bptAmountOut >= _MINIMUM_BPT, Errors.MINIMUM_BPT);
                        _mintPoolTokens(address(0), _MINIMUM_BPT);
                        _mintPoolTokens(recipient, bptAmountOut - _MINIMUM_BPT);
                        // amountsIn are amounts entering the Pool, so we round up.
                        _downscaleUpArray(amountsIn, scalingFactors);
                        return (amountsIn, new uint256[](_getTotalTokens()));
                    } else {
                        _upscaleArray(balances, scalingFactors);
                        (uint256 bptAmountOut, uint256[] memory amountsIn, uint256[] memory dueProtocolFeeAmounts) = _onJoinPool(
                            poolId,
                            sender,
                            recipient,
                            balances,
                            lastChangeBlock,
                            protocolSwapFeePercentage,
                            scalingFactors,
                            userData
                        );
                        // Note we no longer use `balances` after calling `_onJoinPool`, which may mutate it.
                        _mintPoolTokens(recipient, bptAmountOut);
                        // amountsIn are amounts entering the Pool, so we round up.
                        _downscaleUpArray(amountsIn, scalingFactors);
                        // dueProtocolFeeAmounts are amounts exiting the Pool, so we round down.
                        _downscaleDownArray(dueProtocolFeeAmounts, scalingFactors);
                        return (amountsIn, dueProtocolFeeAmounts);
                    }
                }
                function onExitPool(
                    bytes32 poolId,
                    address sender,
                    address recipient,
                    uint256[] memory balances,
                    uint256 lastChangeBlock,
                    uint256 protocolSwapFeePercentage,
                    bytes memory userData
                ) public virtual override onlyVault(poolId) returns (uint256[] memory, uint256[] memory) {
                    uint256[] memory scalingFactors = _scalingFactors();
                    _upscaleArray(balances, scalingFactors);
                    (uint256 bptAmountIn, uint256[] memory amountsOut, uint256[] memory dueProtocolFeeAmounts) = _onExitPool(
                        poolId,
                        sender,
                        recipient,
                        balances,
                        lastChangeBlock,
                        protocolSwapFeePercentage,
                        scalingFactors,
                        userData
                    );
                    // Note we no longer use `balances` after calling `_onExitPool`, which may mutate it.
                    _burnPoolTokens(sender, bptAmountIn);
                    // Both amountsOut and dueProtocolFeeAmounts are amounts exiting the Pool, so we round down.
                    _downscaleDownArray(amountsOut, scalingFactors);
                    _downscaleDownArray(dueProtocolFeeAmounts, scalingFactors);
                    return (amountsOut, dueProtocolFeeAmounts);
                }
                // Query functions
                /**
                 * @dev Returns the amount of BPT that would be granted to `recipient` if the `onJoinPool` hook were called by the
                 * Vault with the same arguments, along with the number of tokens `sender` would have to supply.
                 *
                 * This function is not meant to be called directly, but rather from a helper contract that fetches current Vault
                 * data, such as the protocol swap fee percentage and Pool balances.
                 *
                 * Like `IVault.queryBatchSwap`, this function is not view due to internal implementation details: the caller must
                 * explicitly use eth_call instead of eth_sendTransaction.
                 */
                function queryJoin(
                    bytes32 poolId,
                    address sender,
                    address recipient,
                    uint256[] memory balances,
                    uint256 lastChangeBlock,
                    uint256 protocolSwapFeePercentage,
                    bytes memory userData
                ) external returns (uint256 bptOut, uint256[] memory amountsIn) {
                    InputHelpers.ensureInputLengthMatch(balances.length, _getTotalTokens());
                    _queryAction(
                        poolId,
                        sender,
                        recipient,
                        balances,
                        lastChangeBlock,
                        protocolSwapFeePercentage,
                        userData,
                        _onJoinPool,
                        _downscaleUpArray
                    );
                    // The `return` opcode is executed directly inside `_queryAction`, so execution never reaches this statement,
                    // and we don't need to return anything here - it just silences compiler warnings.
                    return (bptOut, amountsIn);
                }
                /**
                 * @dev Returns the amount of BPT that would be burned from `sender` if the `onExitPool` hook were called by the
                 * Vault with the same arguments, along with the number of tokens `recipient` would receive.
                 *
                 * This function is not meant to be called directly, but rather from a helper contract that fetches current Vault
                 * data, such as the protocol swap fee percentage and Pool balances.
                 *
                 * Like `IVault.queryBatchSwap`, this function is not view due to internal implementation details: the caller must
                 * explicitly use eth_call instead of eth_sendTransaction.
                 */
                function queryExit(
                    bytes32 poolId,
                    address sender,
                    address recipient,
                    uint256[] memory balances,
                    uint256 lastChangeBlock,
                    uint256 protocolSwapFeePercentage,
                    bytes memory userData
                ) external returns (uint256 bptIn, uint256[] memory amountsOut) {
                    InputHelpers.ensureInputLengthMatch(balances.length, _getTotalTokens());
                    _queryAction(
                        poolId,
                        sender,
                        recipient,
                        balances,
                        lastChangeBlock,
                        protocolSwapFeePercentage,
                        userData,
                        _onExitPool,
                        _downscaleDownArray
                    );
                    // The `return` opcode is executed directly inside `_queryAction`, so execution never reaches this statement,
                    // and we don't need to return anything here - it just silences compiler warnings.
                    return (bptIn, amountsOut);
                }
                // Internal hooks to be overridden by derived contracts - all token amounts (except BPT) in these interfaces are
                // upscaled.
                /**
                 * @dev Called when the Pool is joined for the first time; that is, when the BPT total supply is zero.
                 *
                 * Returns the amount of BPT to mint, and the token amounts the Pool will receive in return.
                 *
                 * Minted BPT will be sent to `recipient`, except for _MINIMUM_BPT, which will be deducted from this amount and sent
                 * to the zero address instead. This will cause that BPT to remain forever locked there, preventing total BTP from
                 * ever dropping below that value, and ensuring `_onInitializePool` can only be called once in the entire Pool's
                 * lifetime.
                 *
                 * The tokens granted to the Pool will be transferred from `sender`. These amounts are considered upscaled and will
                 * be downscaled (rounding up) before being returned to the Vault.
                 */
                function _onInitializePool(
                    bytes32 poolId,
                    address sender,
                    address recipient,
                    uint256[] memory scalingFactors,
                    bytes memory userData
                ) internal virtual returns (uint256 bptAmountOut, uint256[] memory amountsIn);
                /**
                 * @dev Called whenever the Pool is joined after the first initialization join (see `_onInitializePool`).
                 *
                 * Returns the amount of BPT to mint, the token amounts that the Pool will receive in return, and the number of
                 * tokens to pay in protocol swap fees.
                 *
                 * Implementations of this function might choose to mutate the `balances` array to save gas (e.g. when
                 * performing intermediate calculations, such as subtraction of due protocol fees). This can be done safely.
                 *
                 * Minted BPT will be sent to `recipient`.
                 *
                 * The tokens granted to the Pool will be transferred from `sender`. These amounts are considered upscaled and will
                 * be downscaled (rounding up) before being returned to the Vault.
                 *
                 * Due protocol swap fees will be taken from the Pool's balance in the Vault (see `IBasePool.onJoinPool`). These
                 * amounts are considered upscaled and will be downscaled (rounding down) before being returned to the Vault.
                 */
                function _onJoinPool(
                    bytes32 poolId,
                    address sender,
                    address recipient,
                    uint256[] memory balances,
                    uint256 lastChangeBlock,
                    uint256 protocolSwapFeePercentage,
                    uint256[] memory scalingFactors,
                    bytes memory userData
                )
                    internal
                    virtual
                    returns (
                        uint256 bptAmountOut,
                        uint256[] memory amountsIn,
                        uint256[] memory dueProtocolFeeAmounts
                    );
                /**
                 * @dev Called whenever the Pool is exited.
                 *
                 * Returns the amount of BPT to burn, the token amounts for each Pool token that the Pool will grant in return, and
                 * the number of tokens to pay in protocol swap fees.
                 *
                 * Implementations of this function might choose to mutate the `balances` array to save gas (e.g. when
                 * performing intermediate calculations, such as subtraction of due protocol fees). This can be done safely.
                 *
                 * BPT will be burnt from `sender`.
                 *
                 * The Pool will grant tokens to `recipient`. These amounts are considered upscaled and will be downscaled
                 * (rounding down) before being returned to the Vault.
                 *
                 * Due protocol swap fees will be taken from the Pool's balance in the Vault (see `IBasePool.onExitPool`). These
                 * amounts are considered upscaled and will be downscaled (rounding down) before being returned to the Vault.
                 */
                function _onExitPool(
                    bytes32 poolId,
                    address sender,
                    address recipient,
                    uint256[] memory balances,
                    uint256 lastChangeBlock,
                    uint256 protocolSwapFeePercentage,
                    uint256[] memory scalingFactors,
                    bytes memory userData
                )
                    internal
                    virtual
                    returns (
                        uint256 bptAmountIn,
                        uint256[] memory amountsOut,
                        uint256[] memory dueProtocolFeeAmounts
                    );
                // Internal functions
                /**
                 * @dev Adds swap fee amount to `amount`, returning a higher value.
                 */
                function _addSwapFeeAmount(uint256 amount) internal view returns (uint256) {
                    // This returns amount + fee amount, so we round up (favoring a higher fee amount).
                    return amount.divUp(FixedPoint.ONE.sub(getSwapFeePercentage()));
                }
                /**
                 * @dev Subtracts swap fee amount from `amount`, returning a lower value.
                 */
                function _subtractSwapFeeAmount(uint256 amount) internal view returns (uint256) {
                    // This returns amount - fee amount, so we round up (favoring a higher fee amount).
                    uint256 feeAmount = amount.mulUp(getSwapFeePercentage());
                    return amount.sub(feeAmount);
                }
                // Scaling
                /**
                 * @dev Returns a scaling factor that, when multiplied to a token amount for `token`, normalizes its balance as if
                 * it had 18 decimals.
                 */
                function _computeScalingFactor(IERC20 token) internal view returns (uint256) {
                    // Tokens that don't implement the `decimals` method are not supported.
                    uint256 tokenDecimals = ERC20(address(token)).decimals();
                    // Tokens with more than 18 decimals are not supported.
                    uint256 decimalsDifference = Math.sub(18, tokenDecimals);
                    return FixedPoint.ONE * 10**decimalsDifference;
                }
                /**
                 * @dev Returns the scaling factor for one of the Pool's tokens. Reverts if `token` is not a token registered by the
                 * Pool.
                 *
                 * All scaling factors are fixed-point values with 18 decimals, to allow for this function to be overridden by
                 * derived contracts that need to apply further scaling, making these factors potentially non-integer.
                 *
                 * The largest 'base' scaling factor (i.e. in tokens with less than 18 decimals) is 10**18, which in fixed-point is
                 * 10**36. This value can be multiplied with a 112 bit Vault balance with no overflow by a factor of ~1e7, making
                 * even relatively 'large' factors safe to use.
                 *
                 * The 1e7 figure is the result of 2**256 / (1e18 * 1e18 * 2**112).
                 */
                function _scalingFactor(IERC20 token) internal view virtual returns (uint256);
                /**
                 * @dev Same as `_scalingFactor()`, except for all registered tokens (in the same order as registered). The Vault
                 * will always pass balances in this order when calling any of the Pool hooks.
                 */
                function _scalingFactors() internal view virtual returns (uint256[] memory);
                function getScalingFactors() external view returns (uint256[] memory) {
                    return _scalingFactors();
                }
                /**
                 * @dev Applies `scalingFactor` to `amount`, resulting in a larger or equal value depending on whether it needed
                 * scaling or not.
                 */
                function _upscale(uint256 amount, uint256 scalingFactor) internal pure returns (uint256) {
                    // Upscale rounding wouldn't necessarily always go in the same direction: in a swap for example the balance of
                    // token in should be rounded up, and that of token out rounded down. This is the only place where we round in
                    // the same direction for all amounts, as the impact of this rounding is expected to be minimal (and there's no
                    // rounding error unless `_scalingFactor()` is overriden).
                    return FixedPoint.mulDown(amount, scalingFactor);
                }
                /**
                 * @dev Same as `_upscale`, but for an entire array. This function does not return anything, but instead *mutates*
                 * the `amounts` array.
                 */
                function _upscaleArray(uint256[] memory amounts, uint256[] memory scalingFactors) internal view {
                    for (uint256 i = 0; i < _getTotalTokens(); ++i) {
                        amounts[i] = FixedPoint.mulDown(amounts[i], scalingFactors[i]);
                    }
                }
                /**
                 * @dev Reverses the `scalingFactor` applied to `amount`, resulting in a smaller or equal value depending on
                 * whether it needed scaling or not. The result is rounded down.
                 */
                function _downscaleDown(uint256 amount, uint256 scalingFactor) internal pure returns (uint256) {
                    return FixedPoint.divDown(amount, scalingFactor);
                }
                /**
                 * @dev Same as `_downscaleDown`, but for an entire array. This function does not return anything, but instead
                 * *mutates* the `amounts` array.
                 */
                function _downscaleDownArray(uint256[] memory amounts, uint256[] memory scalingFactors) internal view {
                    for (uint256 i = 0; i < _getTotalTokens(); ++i) {
                        amounts[i] = FixedPoint.divDown(amounts[i], scalingFactors[i]);
                    }
                }
                /**
                 * @dev Reverses the `scalingFactor` applied to `amount`, resulting in a smaller or equal value depending on
                 * whether it needed scaling or not. The result is rounded up.
                 */
                function _downscaleUp(uint256 amount, uint256 scalingFactor) internal pure returns (uint256) {
                    return FixedPoint.divUp(amount, scalingFactor);
                }
                /**
                 * @dev Same as `_downscaleUp`, but for an entire array. This function does not return anything, but instead
                 * *mutates* the `amounts` array.
                 */
                function _downscaleUpArray(uint256[] memory amounts, uint256[] memory scalingFactors) internal view {
                    for (uint256 i = 0; i < _getTotalTokens(); ++i) {
                        amounts[i] = FixedPoint.divUp(amounts[i], scalingFactors[i]);
                    }
                }
                function _getAuthorizer() internal view override returns (IAuthorizer) {
                    // Access control management is delegated to the Vault's Authorizer. This lets Balancer Governance manage which
                    // accounts can call permissioned functions: for example, to perform emergency pauses.
                    // If the owner is delegated, then *all* permissioned functions, including `setSwapFeePercentage`, will be under
                    // Governance control.
                    return getVault().getAuthorizer();
                }
                function _queryAction(
                    bytes32 poolId,
                    address sender,
                    address recipient,
                    uint256[] memory balances,
                    uint256 lastChangeBlock,
                    uint256 protocolSwapFeePercentage,
                    bytes memory userData,
                    function(bytes32, address, address, uint256[] memory, uint256, uint256, uint256[] memory, bytes memory)
                        internal
                        returns (uint256, uint256[] memory, uint256[] memory) _action,
                    function(uint256[] memory, uint256[] memory) internal view _downscaleArray
                ) private {
                    // This uses the same technique used by the Vault in queryBatchSwap. Refer to that function for a detailed
                    // explanation.
                    if (msg.sender != address(this)) {
                        // We perform an external call to ourselves, forwarding the same calldata. In this call, the else clause of
                        // the preceding if statement will be executed instead.
                        // solhint-disable-next-line avoid-low-level-calls
                        (bool success, ) = address(this).call(msg.data);
                        // solhint-disable-next-line no-inline-assembly
                        assembly {
                            // This call should always revert to decode the bpt and token amounts from the revert reason
                            switch success
                                case 0 {
                                    // Note we are manually writing the memory slot 0. We can safely overwrite whatever is
                                    // stored there as we take full control of the execution and then immediately return.
                                    // We copy the first 4 bytes to check if it matches with the expected signature, otherwise
                                    // there was another revert reason and we should forward it.
                                    returndatacopy(0, 0, 0x04)
                                    let error := and(mload(0), 0xffffffff00000000000000000000000000000000000000000000000000000000)
                                    // If the first 4 bytes don't match with the expected signature, we forward the revert reason.
                                    if eq(eq(error, 0x43adbafb00000000000000000000000000000000000000000000000000000000), 0) {
                                        returndatacopy(0, 0, returndatasize())
                                        revert(0, returndatasize())
                                    }
                                    // The returndata contains the signature, followed by the raw memory representation of the
                                    // `bptAmount` and `tokenAmounts` (array: length + data). We need to return an ABI-encoded
                                    // representation of these.
                                    // An ABI-encoded response will include one additional field to indicate the starting offset of
                                    // the `tokenAmounts` array. The `bptAmount` will be laid out in the first word of the
                                    // returndata.
                                    //
                                    // In returndata:
                                    // [ signature ][ bptAmount ][ tokenAmounts length ][ tokenAmounts values ]
                                    // [  4 bytes  ][  32 bytes ][       32 bytes      ][ (32 * length) bytes ]
                                    //
                                    // We now need to return (ABI-encoded values):
                                    // [ bptAmount ][ tokeAmounts offset ][ tokenAmounts length ][ tokenAmounts values ]
                                    // [  32 bytes ][       32 bytes     ][       32 bytes      ][ (32 * length) bytes ]
                                    // We copy 32 bytes for the `bptAmount` from returndata into memory.
                                    // Note that we skip the first 4 bytes for the error signature
                                    returndatacopy(0, 0x04, 32)
                                    // The offsets are 32-bytes long, so the array of `tokenAmounts` will start after
                                    // the initial 64 bytes.
                                    mstore(0x20, 64)
                                    // We now copy the raw memory array for the `tokenAmounts` from returndata into memory.
                                    // Since bpt amount and offset take up 64 bytes, we start copying at address 0x40. We also
                                    // skip the first 36 bytes from returndata, which correspond to the signature plus bpt amount.
                                    returndatacopy(0x40, 0x24, sub(returndatasize(), 36))
                                    // We finally return the ABI-encoded uint256 and the array, which has a total length equal to
                                    // the size of returndata, plus the 32 bytes of the offset but without the 4 bytes of the
                                    // error signature.
                                    return(0, add(returndatasize(), 28))
                                }
                                default {
                                    // This call should always revert, but we fail nonetheless if that didn't happen
                                    invalid()
                                }
                        }
                    } else {
                        uint256[] memory scalingFactors = _scalingFactors();
                        _upscaleArray(balances, scalingFactors);
                        (uint256 bptAmount, uint256[] memory tokenAmounts, ) = _action(
                            poolId,
                            sender,
                            recipient,
                            balances,
                            lastChangeBlock,
                            protocolSwapFeePercentage,
                            scalingFactors,
                            userData
                        );
                        _downscaleArray(tokenAmounts, scalingFactors);
                        // solhint-disable-next-line no-inline-assembly
                        assembly {
                            // We will return a raw representation of `bptAmount` and `tokenAmounts` in memory, which is composed of
                            // a 32-byte uint256, followed by a 32-byte for the array length, and finally the 32-byte uint256 values
                            // Because revert expects a size in bytes, we multiply the array length (stored at `tokenAmounts`) by 32
                            let size := mul(mload(tokenAmounts), 32)
                            // We store the `bptAmount` in the previous slot to the `tokenAmounts` array. We can make sure there
                            // will be at least one available slot due to how the memory scratch space works.
                            // We can safely overwrite whatever is stored in this slot as we will revert immediately after that.
                            let start := sub(tokenAmounts, 0x20)
                            mstore(start, bptAmount)
                            // We send one extra value for the error signature "QueryError(uint256,uint256[])" which is 0x43adbafb
                            // We use the previous slot to `bptAmount`.
                            mstore(sub(start, 0x20), 0x0000000000000000000000000000000000000000000000000000000043adbafb)
                            start := sub(start, 0x04)
                            // When copying from `tokenAmounts` into returndata, we copy the additional 68 bytes to also return
                            // the `bptAmount`, the array 's length, and the error signature.
                            revert(start, add(size, 68))
                        }
                    }
                }
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            pragma experimental ABIEncoderV2;
            import "./IBasePool.sol";
            /**
             * @dev Pool contracts with the MinimalSwapInfo or TwoToken specialization settings should implement this interface.
             *
             * This is called by the Vault when a user calls `IVault.swap` or `IVault.batchSwap` to swap with this Pool.
             * Returns the number of tokens the Pool will grant to the user in a 'given in' swap, or that the user will grant
             * to the pool in a 'given out' swap.
             *
             * This can often be implemented by a `view` function, since many pricing algorithms don't need to track state
             * changes in swaps. However, contracts implementing this in non-view functions should check that the caller is
             * indeed the Vault.
             */
            interface IMinimalSwapInfoPool is IBasePool {
                function onSwap(
                    SwapRequest memory swapRequest,
                    uint256 currentBalanceTokenIn,
                    uint256 currentBalanceTokenOut
                ) external returns (uint256 amount);
            }
            // SPDX-License-Identifier: MIT
            pragma solidity ^0.7.0;
            import "../helpers/BalancerErrors.sol";
            /**
             * @dev Wrappers over Solidity's arithmetic operations with added overflow checks.
             * Adapted from OpenZeppelin's SafeMath library
             */
            library Math {
                /**
                 * @dev Returns the addition of two unsigned integers of 256 bits, reverting on overflow.
                 */
                function add(uint256 a, uint256 b) internal pure returns (uint256) {
                    uint256 c = a + b;
                    _require(c >= a, Errors.ADD_OVERFLOW);
                    return c;
                }
                /**
                 * @dev Returns the addition of two signed integers, reverting on overflow.
                 */
                function add(int256 a, int256 b) internal pure returns (int256) {
                    int256 c = a + b;
                    _require((b >= 0 && c >= a) || (b < 0 && c < a), Errors.ADD_OVERFLOW);
                    return c;
                }
                /**
                 * @dev Returns the subtraction of two unsigned integers of 256 bits, reverting on overflow.
                 */
                function sub(uint256 a, uint256 b) internal pure returns (uint256) {
                    _require(b <= a, Errors.SUB_OVERFLOW);
                    uint256 c = a - b;
                    return c;
                }
                /**
                 * @dev Returns the subtraction of two signed integers, reverting on overflow.
                 */
                function sub(int256 a, int256 b) internal pure returns (int256) {
                    int256 c = a - b;
                    _require((b >= 0 && c <= a) || (b < 0 && c > a), Errors.SUB_OVERFLOW);
                    return c;
                }
                /**
                 * @dev Returns the largest of two numbers of 256 bits.
                 */
                function max(uint256 a, uint256 b) internal pure returns (uint256) {
                    return a >= b ? a : b;
                }
                /**
                 * @dev Returns the smallest of two numbers of 256 bits.
                 */
                function min(uint256 a, uint256 b) internal pure returns (uint256) {
                    return a < b ? a : b;
                }
                function mul(uint256 a, uint256 b) internal pure returns (uint256) {
                    uint256 c = a * b;
                    _require(a == 0 || c / a == b, Errors.MUL_OVERFLOW);
                    return c;
                }
                function div(
                    uint256 a,
                    uint256 b,
                    bool roundUp
                ) internal pure returns (uint256) {
                    return roundUp ? divUp(a, b) : divDown(a, b);
                }
                function divDown(uint256 a, uint256 b) internal pure returns (uint256) {
                    _require(b != 0, Errors.ZERO_DIVISION);
                    return a / b;
                }
                function divUp(uint256 a, uint256 b) internal pure returns (uint256) {
                    _require(b != 0, Errors.ZERO_DIVISION);
                    if (a == 0) {
                        return 0;
                    } else {
                        return 1 + (a - 1) / b;
                    }
                }
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            import "./BalancerErrors.sol";
            import "./ITemporarilyPausable.sol";
            /**
             * @dev Allows for a contract to be paused during an initial period after deployment, disabling functionality. Can be
             * used as an emergency switch in case a security vulnerability or threat is identified.
             *
             * The contract can only be paused during the Pause Window, a period that starts at deployment. It can also be
             * unpaused and repaused any number of times during this period. This is intended to serve as a safety measure: it lets
             * system managers react quickly to potentially dangerous situations, knowing that this action is reversible if careful
             * analysis later determines there was a false alarm.
             *
             * If the contract is paused when the Pause Window finishes, it will remain in the paused state through an additional
             * Buffer Period, after which it will be automatically unpaused forever. This is to ensure there is always enough time
             * to react to an emergency, even if the threat is discovered shortly before the Pause Window expires.
             *
             * Note that since the contract can only be paused within the Pause Window, unpausing during the Buffer Period is
             * irreversible.
             */
            abstract contract TemporarilyPausable is ITemporarilyPausable {
                // The Pause Window and Buffer Period are timestamp-based: they should not be relied upon for sub-minute accuracy.
                // solhint-disable not-rely-on-time
                uint256 private constant _MAX_PAUSE_WINDOW_DURATION = 90 days;
                uint256 private constant _MAX_BUFFER_PERIOD_DURATION = 30 days;
                uint256 private immutable _pauseWindowEndTime;
                uint256 private immutable _bufferPeriodEndTime;
                bool private _paused;
                constructor(uint256 pauseWindowDuration, uint256 bufferPeriodDuration) {
                    _require(pauseWindowDuration <= _MAX_PAUSE_WINDOW_DURATION, Errors.MAX_PAUSE_WINDOW_DURATION);
                    _require(bufferPeriodDuration <= _MAX_BUFFER_PERIOD_DURATION, Errors.MAX_BUFFER_PERIOD_DURATION);
                    uint256 pauseWindowEndTime = block.timestamp + pauseWindowDuration;
                    _pauseWindowEndTime = pauseWindowEndTime;
                    _bufferPeriodEndTime = pauseWindowEndTime + bufferPeriodDuration;
                }
                /**
                 * @dev Reverts if the contract is paused.
                 */
                modifier whenNotPaused() {
                    _ensureNotPaused();
                    _;
                }
                /**
                 * @dev Returns the current contract pause status, as well as the end times of the Pause Window and Buffer
                 * Period.
                 */
                function getPausedState()
                    external
                    view
                    override
                    returns (
                        bool paused,
                        uint256 pauseWindowEndTime,
                        uint256 bufferPeriodEndTime
                    )
                {
                    paused = !_isNotPaused();
                    pauseWindowEndTime = _getPauseWindowEndTime();
                    bufferPeriodEndTime = _getBufferPeriodEndTime();
                }
                /**
                 * @dev Sets the pause state to `paused`. The contract can only be paused until the end of the Pause Window, and
                 * unpaused until the end of the Buffer Period.
                 *
                 * Once the Buffer Period expires, this function reverts unconditionally.
                 */
                function _setPaused(bool paused) internal {
                    if (paused) {
                        _require(block.timestamp < _getPauseWindowEndTime(), Errors.PAUSE_WINDOW_EXPIRED);
                    } else {
                        _require(block.timestamp < _getBufferPeriodEndTime(), Errors.BUFFER_PERIOD_EXPIRED);
                    }
                    _paused = paused;
                    emit PausedStateChanged(paused);
                }
                /**
                 * @dev Reverts if the contract is paused.
                 */
                function _ensureNotPaused() internal view {
                    _require(_isNotPaused(), Errors.PAUSED);
                }
                /**
                 * @dev Returns true if the contract is unpaused.
                 *
                 * Once the Buffer Period expires, the gas cost of calling this function is reduced dramatically, as storage is no
                 * longer accessed.
                 */
                function _isNotPaused() internal view returns (bool) {
                    // After the Buffer Period, the (inexpensive) timestamp check short-circuits the storage access.
                    return block.timestamp > _getBufferPeriodEndTime() || !_paused;
                }
                // These getters lead to reduced bytecode size by inlining the immutable variables in a single place.
                function _getPauseWindowEndTime() private view returns (uint256) {
                    return _pauseWindowEndTime;
                }
                function _getBufferPeriodEndTime() private view returns (uint256) {
                    return _bufferPeriodEndTime;
                }
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            /**
             * @dev Library for encoding and decoding values stored inside a 256 bit word. Typically used to pack multiple values in
             * a single storage slot, saving gas by performing less storage accesses.
             *
             * Each value is defined by its size and the least significant bit in the word, also known as offset. For example, two
             * 128 bit values may be encoded in a word by assigning one an offset of 0, and the other an offset of 128.
             */
            library WordCodec {
                // Masks are values with the least significant N bits set. They can be used to extract an encoded value from a word,
                // or to insert a new one replacing the old.
                uint256 private constant _MASK_1 = 2**(1) - 1;
                uint256 private constant _MASK_10 = 2**(10) - 1;
                uint256 private constant _MASK_16 = 2**(16) - 1;
                uint256 private constant _MASK_22 = 2**(22) - 1;
                uint256 private constant _MASK_31 = 2**(31) - 1;
                uint256 private constant _MASK_32 = 2**(32) - 1;
                uint256 private constant _MASK_53 = 2**(53) - 1;
                uint256 private constant _MASK_64 = 2**(64) - 1;
                uint256 private constant _MASK_128 = 2**(128) - 1;
                uint256 private constant _MASK_192 = 2**(192) - 1;
                // Largest positive values that can be represented as N bits signed integers.
                int256 private constant _MAX_INT_22 = 2**(21) - 1;
                int256 private constant _MAX_INT_53 = 2**(52) - 1;
                // In-place insertion
                /**
                 * @dev Inserts a boolean value shifted by an offset into a 256 bit word, replacing the old value. Returns the new
                 * word.
                 */
                function insertBool(
                    bytes32 word,
                    bool value,
                    uint256 offset
                ) internal pure returns (bytes32) {
                    bytes32 clearedWord = bytes32(uint256(word) & ~(_MASK_1 << offset));
                    return clearedWord | bytes32(uint256(value ? 1 : 0) << offset);
                }
                // Unsigned
                /**
                 * @dev Inserts a 10 bit unsigned integer shifted by an offset into a 256 bit word, replacing the old value. Returns
                 * the new word.
                 *
                 * Assumes `value` only uses its least significant 10 bits, otherwise it may overwrite sibling bytes.
                 */
                function insertUint10(
                    bytes32 word,
                    uint256 value,
                    uint256 offset
                ) internal pure returns (bytes32) {
                    bytes32 clearedWord = bytes32(uint256(word) & ~(_MASK_10 << offset));
                    return clearedWord | bytes32(value << offset);
                }
                /**
                 * @dev Inserts a 16 bit unsigned integer shifted by an offset into a 256 bit word, replacing the old value.
                 * Returns the new word.
                 *
                 * Assumes `value` only uses its least significant 16 bits, otherwise it may overwrite sibling bytes.
                 */
                function insertUint16(
                    bytes32 word,
                    uint256 value,
                    uint256 offset
                ) internal pure returns (bytes32) {
                    bytes32 clearedWord = bytes32(uint256(word) & ~(_MASK_16 << offset));
                    return clearedWord | bytes32(value << offset);
                }
                /**
                 * @dev Inserts a 31 bit unsigned integer shifted by an offset into a 256 bit word, replacing the old value. Returns
                 * the new word.
                 *
                 * Assumes `value` can be represented using 31 bits.
                 */
                function insertUint31(
                    bytes32 word,
                    uint256 value,
                    uint256 offset
                ) internal pure returns (bytes32) {
                    bytes32 clearedWord = bytes32(uint256(word) & ~(_MASK_31 << offset));
                    return clearedWord | bytes32(value << offset);
                }
                /**
                 * @dev Inserts a 32 bit unsigned integer shifted by an offset into a 256 bit word, replacing the old value. Returns
                 * the new word.
                 *
                 * Assumes `value` only uses its least significant 32 bits, otherwise it may overwrite sibling bytes.
                 */
                function insertUint32(
                    bytes32 word,
                    uint256 value,
                    uint256 offset
                ) internal pure returns (bytes32) {
                    bytes32 clearedWord = bytes32(uint256(word) & ~(_MASK_32 << offset));
                    return clearedWord | bytes32(value << offset);
                }
                /**
                 * @dev Inserts a 64 bit unsigned integer shifted by an offset into a 256 bit word, replacing the old value. Returns
                 * the new word.
                 *
                 * Assumes `value` only uses its least significant 64 bits, otherwise it may overwrite sibling bytes.
                 */
                function insertUint64(
                    bytes32 word,
                    uint256 value,
                    uint256 offset
                ) internal pure returns (bytes32) {
                    bytes32 clearedWord = bytes32(uint256(word) & ~(_MASK_64 << offset));
                    return clearedWord | bytes32(value << offset);
                }
                // Signed
                /**
                 * @dev Inserts a 22 bits signed integer shifted by an offset into a 256 bit word, replacing the old value. Returns
                 * the new word.
                 *
                 * Assumes `value` can be represented using 22 bits.
                 */
                function insertInt22(
                    bytes32 word,
                    int256 value,
                    uint256 offset
                ) internal pure returns (bytes32) {
                    bytes32 clearedWord = bytes32(uint256(word) & ~(_MASK_22 << offset));
                    // Integer values need masking to remove the upper bits of negative values.
                    return clearedWord | bytes32((uint256(value) & _MASK_22) << offset);
                }
                // Bytes
                /**
                 * @dev Inserts 192 bit shifted by an offset into a 256 bit word, replacing the old value. Returns the new word.
                 *
                 * Assumes `value` can be represented using 192 bits.
                 */
                function insertBits192(
                    bytes32 word,
                    bytes32 value,
                    uint256 offset
                ) internal pure returns (bytes32) {
                    bytes32 clearedWord = bytes32(uint256(word) & ~(_MASK_192 << offset));
                    return clearedWord | bytes32((uint256(value) & _MASK_192) << offset);
                }
                // Encoding
                // Unsigned
                /**
                 * @dev Encodes an unsigned integer shifted by an offset. This performs no size checks: it is up to the caller to
                 * ensure that the values are bounded.
                 *
                 * The return value can be logically ORed with other encoded values to form a 256 bit word.
                 */
                function encodeUint(uint256 value, uint256 offset) internal pure returns (bytes32) {
                    return bytes32(value << offset);
                }
                // Signed
                /**
                 * @dev Encodes a 22 bits signed integer shifted by an offset.
                 *
                 * The return value can be logically ORed with other encoded values to form a 256 bit word.
                 */
                function encodeInt22(int256 value, uint256 offset) internal pure returns (bytes32) {
                    // Integer values need masking to remove the upper bits of negative values.
                    return bytes32((uint256(value) & _MASK_22) << offset);
                }
                /**
                 * @dev Encodes a 53 bits signed integer shifted by an offset.
                 *
                 * The return value can be logically ORed with other encoded values to form a 256 bit word.
                 */
                function encodeInt53(int256 value, uint256 offset) internal pure returns (bytes32) {
                    // Integer values need masking to remove the upper bits of negative values.
                    return bytes32((uint256(value) & _MASK_53) << offset);
                }
                // Decoding
                /**
                 * @dev Decodes and returns a boolean shifted by an offset from a 256 bit word.
                 */
                function decodeBool(bytes32 word, uint256 offset) internal pure returns (bool) {
                    return (uint256(word >> offset) & _MASK_1) == 1;
                }
                // Unsigned
                /**
                 * @dev Decodes and returns a 10 bit unsigned integer shifted by an offset from a 256 bit word.
                 */
                function decodeUint10(bytes32 word, uint256 offset) internal pure returns (uint256) {
                    return uint256(word >> offset) & _MASK_10;
                }
                /**
                 * @dev Decodes and returns a 16 bit unsigned integer shifted by an offset from a 256 bit word.
                 */
                function decodeUint16(bytes32 word, uint256 offset) internal pure returns (uint256) {
                    return uint256(word >> offset) & _MASK_16;
                }
                /**
                 * @dev Decodes and returns a 31 bit unsigned integer shifted by an offset from a 256 bit word.
                 */
                function decodeUint31(bytes32 word, uint256 offset) internal pure returns (uint256) {
                    return uint256(word >> offset) & _MASK_31;
                }
                /**
                 * @dev Decodes and returns a 32 bit unsigned integer shifted by an offset from a 256 bit word.
                 */
                function decodeUint32(bytes32 word, uint256 offset) internal pure returns (uint256) {
                    return uint256(word >> offset) & _MASK_32;
                }
                /**
                 * @dev Decodes and returns a 64 bit unsigned integer shifted by an offset from a 256 bit word.
                 */
                function decodeUint64(bytes32 word, uint256 offset) internal pure returns (uint256) {
                    return uint256(word >> offset) & _MASK_64;
                }
                /**
                 * @dev Decodes and returns a 128 bit unsigned integer shifted by an offset from a 256 bit word.
                 */
                function decodeUint128(bytes32 word, uint256 offset) internal pure returns (uint256) {
                    return uint256(word >> offset) & _MASK_128;
                }
                // Signed
                /**
                 * @dev Decodes and returns a 22 bits signed integer shifted by an offset from a 256 bit word.
                 */
                function decodeInt22(bytes32 word, uint256 offset) internal pure returns (int256) {
                    int256 value = int256(uint256(word >> offset) & _MASK_22);
                    // In case the decoded value is greater than the max positive integer that can be represented with 22 bits,
                    // we know it was originally a negative integer. Therefore, we mask it to restore the sign in the 256 bit
                    // representation.
                    return value > _MAX_INT_22 ? (value | int256(~_MASK_22)) : value;
                }
                /**
                 * @dev Decodes and returns a 53 bits signed integer shifted by an offset from a 256 bit word.
                 */
                function decodeInt53(bytes32 word, uint256 offset) internal pure returns (int256) {
                    int256 value = int256(uint256(word >> offset) & _MASK_53);
                    // In case the decoded value is greater than the max positive integer that can be represented with 53 bits,
                    // we know it was originally a negative integer. Therefore, we mask it to restore the sign in the 256 bit
                    // representation.
                    return value > _MAX_INT_53 ? (value | int256(~_MASK_53)) : value;
                }
            }
            // SPDX-License-Identifier: MIT
            pragma solidity ^0.7.0;
            import "../helpers/BalancerErrors.sol";
            import "./IERC20.sol";
            import "./SafeMath.sol";
            /**
             * @dev Implementation of the {IERC20} interface.
             *
             * This implementation is agnostic to the way tokens are created. This means
             * that a supply mechanism has to be added in a derived contract using {_mint}.
             * For a generic mechanism see {ERC20PresetMinterPauser}.
             *
             * TIP: For a detailed writeup see our guide
             * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
             * to implement supply mechanisms].
             *
             * We have followed general OpenZeppelin guidelines: functions revert instead
             * of returning `false` on failure. This behavior is nonetheless conventional
             * and does not conflict with the expectations of ERC20 applications.
             *
             * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
             * This allows applications to reconstruct the allowance for all accounts just
             * by listening to said events. Other implementations of the EIP may not emit
             * these events, as it isn't required by the specification.
             *
             * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
             * functions have been added to mitigate the well-known issues around setting
             * allowances. See {IERC20-approve}.
             */
            contract ERC20 is IERC20 {
                using SafeMath for uint256;
                mapping(address => uint256) private _balances;
                mapping(address => mapping(address => uint256)) private _allowances;
                uint256 private _totalSupply;
                string private _name;
                string private _symbol;
                uint8 private _decimals;
                /**
                 * @dev Sets the values for {name} and {symbol}, initializes {decimals} with
                 * a default value of 18.
                 *
                 * To select a different value for {decimals}, use {_setupDecimals}.
                 *
                 * All three of these values are immutable: they can only be set once during
                 * construction.
                 */
                constructor(string memory name_, string memory symbol_) {
                    _name = name_;
                    _symbol = symbol_;
                    _decimals = 18;
                }
                /**
                 * @dev Returns the name of the token.
                 */
                function name() public view returns (string memory) {
                    return _name;
                }
                /**
                 * @dev Returns the symbol of the token, usually a shorter version of the
                 * name.
                 */
                function symbol() public view returns (string memory) {
                    return _symbol;
                }
                /**
                 * @dev Returns the number of decimals used to get its user representation.
                 * For example, if `decimals` equals `2`, a balance of `505` tokens should
                 * be displayed to a user as `5,05` (`505 / 10 ** 2`).
                 *
                 * Tokens usually opt for a value of 18, imitating the relationship between
                 * Ether and Wei. This is the value {ERC20} uses, unless {_setupDecimals} is
                 * called.
                 *
                 * NOTE: This information is only used for _display_ purposes: it in
                 * no way affects any of the arithmetic of the contract, including
                 * {IERC20-balanceOf} and {IERC20-transfer}.
                 */
                function decimals() public view returns (uint8) {
                    return _decimals;
                }
                /**
                 * @dev See {IERC20-totalSupply}.
                 */
                function totalSupply() public view override returns (uint256) {
                    return _totalSupply;
                }
                /**
                 * @dev See {IERC20-balanceOf}.
                 */
                function balanceOf(address account) public view override returns (uint256) {
                    return _balances[account];
                }
                /**
                 * @dev See {IERC20-transfer}.
                 *
                 * Requirements:
                 *
                 * - `recipient` cannot be the zero address.
                 * - the caller must have a balance of at least `amount`.
                 */
                function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
                    _transfer(msg.sender, recipient, amount);
                    return true;
                }
                /**
                 * @dev See {IERC20-allowance}.
                 */
                function allowance(address owner, address spender) public view virtual override returns (uint256) {
                    return _allowances[owner][spender];
                }
                /**
                 * @dev See {IERC20-approve}.
                 *
                 * Requirements:
                 *
                 * - `spender` cannot be the zero address.
                 */
                function approve(address spender, uint256 amount) public virtual override returns (bool) {
                    _approve(msg.sender, spender, amount);
                    return true;
                }
                /**
                 * @dev See {IERC20-transferFrom}.
                 *
                 * Emits an {Approval} event indicating the updated allowance. This is not
                 * required by the EIP. See the note at the beginning of {ERC20}.
                 *
                 * Requirements:
                 *
                 * - `sender` and `recipient` cannot be the zero address.
                 * - `sender` must have a balance of at least `amount`.
                 * - the caller must have allowance for ``sender``'s tokens of at least
                 * `amount`.
                 */
                function transferFrom(
                    address sender,
                    address recipient,
                    uint256 amount
                ) public virtual override returns (bool) {
                    _transfer(sender, recipient, amount);
                    _approve(
                        sender,
                        msg.sender,
                        _allowances[sender][msg.sender].sub(amount, Errors.ERC20_TRANSFER_EXCEEDS_ALLOWANCE)
                    );
                    return true;
                }
                /**
                 * @dev Atomically increases the allowance granted to `spender` by the caller.
                 *
                 * This is an alternative to {approve} that can be used as a mitigation for
                 * problems described in {IERC20-approve}.
                 *
                 * Emits an {Approval} event indicating the updated allowance.
                 *
                 * Requirements:
                 *
                 * - `spender` cannot be the zero address.
                 */
                function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
                    _approve(msg.sender, spender, _allowances[msg.sender][spender].add(addedValue));
                    return true;
                }
                /**
                 * @dev Atomically decreases the allowance granted to `spender` by the caller.
                 *
                 * This is an alternative to {approve} that can be used as a mitigation for
                 * problems described in {IERC20-approve}.
                 *
                 * Emits an {Approval} event indicating the updated allowance.
                 *
                 * Requirements:
                 *
                 * - `spender` cannot be the zero address.
                 * - `spender` must have allowance for the caller of at least
                 * `subtractedValue`.
                 */
                function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
                    _approve(
                        msg.sender,
                        spender,
                        _allowances[msg.sender][spender].sub(subtractedValue, Errors.ERC20_DECREASED_ALLOWANCE_BELOW_ZERO)
                    );
                    return true;
                }
                /**
                 * @dev Moves tokens `amount` from `sender` to `recipient`.
                 *
                 * This is internal function is equivalent to {transfer}, and can be used to
                 * e.g. implement automatic token fees, slashing mechanisms, etc.
                 *
                 * Emits a {Transfer} event.
                 *
                 * Requirements:
                 *
                 * - `sender` cannot be the zero address.
                 * - `recipient` cannot be the zero address.
                 * - `sender` must have a balance of at least `amount`.
                 */
                function _transfer(
                    address sender,
                    address recipient,
                    uint256 amount
                ) internal virtual {
                    _require(sender != address(0), Errors.ERC20_TRANSFER_FROM_ZERO_ADDRESS);
                    _require(recipient != address(0), Errors.ERC20_TRANSFER_TO_ZERO_ADDRESS);
                    _beforeTokenTransfer(sender, recipient, amount);
                    _balances[sender] = _balances[sender].sub(amount, Errors.ERC20_TRANSFER_EXCEEDS_BALANCE);
                    _balances[recipient] = _balances[recipient].add(amount);
                    emit Transfer(sender, recipient, amount);
                }
                /** @dev Creates `amount` tokens and assigns them to `account`, increasing
                 * the total supply.
                 *
                 * Emits a {Transfer} event with `from` set to the zero address.
                 *
                 * Requirements:
                 *
                 * - `to` cannot be the zero address.
                 */
                function _mint(address account, uint256 amount) internal virtual {
                    _beforeTokenTransfer(address(0), account, amount);
                    _totalSupply = _totalSupply.add(amount);
                    _balances[account] = _balances[account].add(amount);
                    emit Transfer(address(0), account, amount);
                }
                /**
                 * @dev Destroys `amount` tokens from `account`, reducing the
                 * total supply.
                 *
                 * Emits a {Transfer} event with `to` set to the zero address.
                 *
                 * Requirements:
                 *
                 * - `account` cannot be the zero address.
                 * - `account` must have at least `amount` tokens.
                 */
                function _burn(address account, uint256 amount) internal virtual {
                    _require(account != address(0), Errors.ERC20_BURN_FROM_ZERO_ADDRESS);
                    _beforeTokenTransfer(account, address(0), amount);
                    _balances[account] = _balances[account].sub(amount, Errors.ERC20_BURN_EXCEEDS_ALLOWANCE);
                    _totalSupply = _totalSupply.sub(amount);
                    emit Transfer(account, address(0), amount);
                }
                /**
                 * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
                 *
                 * This internal function is equivalent to `approve`, and can be used to
                 * e.g. set automatic allowances for certain subsystems, etc.
                 *
                 * Emits an {Approval} event.
                 *
                 * Requirements:
                 *
                 * - `owner` cannot be the zero address.
                 * - `spender` cannot be the zero address.
                 */
                function _approve(
                    address owner,
                    address spender,
                    uint256 amount
                ) internal virtual {
                    _allowances[owner][spender] = amount;
                    emit Approval(owner, spender, amount);
                }
                /**
                 * @dev Sets {decimals} to a value other than the default one of 18.
                 *
                 * WARNING: This function should only be called from the constructor. Most
                 * applications that interact with token contracts will not expect
                 * {decimals} to ever change, and may work incorrectly if it does.
                 */
                function _setupDecimals(uint8 decimals_) internal {
                    _decimals = decimals_;
                }
                /**
                 * @dev Hook that is called before any transfer of tokens. This includes
                 * minting and burning.
                 *
                 * Calling conditions:
                 *
                 * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
                 * will be to transferred to `to`.
                 * - when `from` is zero, `amount` tokens will be minted for `to`.
                 * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
                 * - `from` and `to` are never both zero.
                 *
                 * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
                 */
                function _beforeTokenTransfer(
                    address from,
                    address to,
                    uint256 amount
                ) internal virtual {}
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma experimental ABIEncoderV2;
            import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/IERC20.sol";
            import "@balancer-labs/v2-solidity-utils/contracts/helpers/ISignaturesValidator.sol";
            import "@balancer-labs/v2-solidity-utils/contracts/helpers/ITemporarilyPausable.sol";
            import "@balancer-labs/v2-solidity-utils/contracts/misc/IWETH.sol";
            import "./IAsset.sol";
            import "./IAuthorizer.sol";
            import "./IFlashLoanRecipient.sol";
            import "./IProtocolFeesCollector.sol";
            pragma solidity ^0.7.0;
            /**
             * @dev Full external interface for the Vault core contract - no external or public methods exist in the contract that
             * don't override one of these declarations.
             */
            interface IVault is ISignaturesValidator, ITemporarilyPausable {
                // Generalities about the Vault:
                //
                // - Whenever documentation refers to 'tokens', it strictly refers to ERC20-compliant token contracts. Tokens are
                // transferred out of the Vault by calling the `IERC20.transfer` function, and transferred in by calling
                // `IERC20.transferFrom`. In these cases, the sender must have previously allowed the Vault to use their tokens by
                // calling `IERC20.approve`. The only deviation from the ERC20 standard that is supported is functions not returning
                // a boolean value: in these scenarios, a non-reverting call is assumed to be successful.
                //
                // - All non-view functions in the Vault are non-reentrant: calling them while another one is mid-execution (e.g.
                // while execution control is transferred to a token contract during a swap) will result in a revert. View
                // functions can be called in a re-reentrant way, but doing so might cause them to return inconsistent results.
                // Contracts calling view functions in the Vault must make sure the Vault has not already been entered.
                //
                // - View functions revert if referring to either unregistered Pools, or unregistered tokens for registered Pools.
                // Authorizer
                //
                // Some system actions are permissioned, like setting and collecting protocol fees. This permissioning system exists
                // outside of the Vault in the Authorizer contract: the Vault simply calls the Authorizer to check if the caller
                // can perform a given action.
                /**
                 * @dev Returns the Vault's Authorizer.
                 */
                function getAuthorizer() external view returns (IAuthorizer);
                /**
                 * @dev Sets a new Authorizer for the Vault. The caller must be allowed by the current Authorizer to do this.
                 *
                 * Emits an `AuthorizerChanged` event.
                 */
                function setAuthorizer(IAuthorizer newAuthorizer) external;
                /**
                 * @dev Emitted when a new authorizer is set by `setAuthorizer`.
                 */
                event AuthorizerChanged(IAuthorizer indexed newAuthorizer);
                // Relayers
                //
                // Additionally, it is possible for an account to perform certain actions on behalf of another one, using their
                // Vault ERC20 allowance and Internal Balance. These accounts are said to be 'relayers' for these Vault functions,
                // and are expected to be smart contracts with sound authentication mechanisms. For an account to be able to wield
                // this power, two things must occur:
                //  - The Authorizer must grant the account the permission to be a relayer for the relevant Vault function. This
                //    means that Balancer governance must approve each individual contract to act as a relayer for the intended
                //    functions.
                //  - Each user must approve the relayer to act on their behalf.
                // This double protection means users cannot be tricked into approving malicious relayers (because they will not
                // have been allowed by the Authorizer via governance), nor can malicious relayers approved by a compromised
                // Authorizer or governance drain user funds, since they would also need to be approved by each individual user.
                /**
                 * @dev Returns true if `user` has approved `relayer` to act as a relayer for them.
                 */
                function hasApprovedRelayer(address user, address relayer) external view returns (bool);
                /**
                 * @dev Allows `relayer` to act as a relayer for `sender` if `approved` is true, and disallows it otherwise.
                 *
                 * Emits a `RelayerApprovalChanged` event.
                 */
                function setRelayerApproval(
                    address sender,
                    address relayer,
                    bool approved
                ) external;
                /**
                 * @dev Emitted every time a relayer is approved or disapproved by `setRelayerApproval`.
                 */
                event RelayerApprovalChanged(address indexed relayer, address indexed sender, bool approved);
                // Internal Balance
                //
                // Users can deposit tokens into the Vault, where they are allocated to their Internal Balance, and later
                // transferred or withdrawn. It can also be used as a source of tokens when joining Pools, as a destination
                // when exiting them, and as either when performing swaps. This usage of Internal Balance results in greatly reduced
                // gas costs when compared to relying on plain ERC20 transfers, leading to large savings for frequent users.
                //
                // Internal Balance management features batching, which means a single contract call can be used to perform multiple
                // operations of different kinds, with different senders and recipients, at once.
                /**
                 * @dev Returns `user`'s Internal Balance for a set of tokens.
                 */
                function getInternalBalance(address user, IERC20[] memory tokens) external view returns (uint256[] memory);
                /**
                 * @dev Performs a set of user balance operations, which involve Internal Balance (deposit, withdraw or transfer)
                 * and plain ERC20 transfers using the Vault's allowance. This last feature is particularly useful for relayers, as
                 * it lets integrators reuse a user's Vault allowance.
                 *
                 * For each operation, if the caller is not `sender`, it must be an authorized relayer for them.
                 */
                function manageUserBalance(UserBalanceOp[] memory ops) external payable;
                /**
                 * @dev Data for `manageUserBalance` operations, which include the possibility for ETH to be sent and received
                 without manual WETH wrapping or unwrapping.
                 */
                struct UserBalanceOp {
                    UserBalanceOpKind kind;
                    IAsset asset;
                    uint256 amount;
                    address sender;
                    address payable recipient;
                }
                // There are four possible operations in `manageUserBalance`:
                //
                // - DEPOSIT_INTERNAL
                // Increases the Internal Balance of the `recipient` account by transferring tokens from the corresponding
                // `sender`. The sender must have allowed the Vault to use their tokens via `IERC20.approve()`.
                //
                // ETH can be used by passing the ETH sentinel value as the asset and forwarding ETH in the call: it will be wrapped
                // and deposited as WETH. Any ETH amount remaining will be sent back to the caller (not the sender, which is
                // relevant for relayers).
                //
                // Emits an `InternalBalanceChanged` event.
                //
                //
                // - WITHDRAW_INTERNAL
                // Decreases the Internal Balance of the `sender` account by transferring tokens to the `recipient`.
                //
                // ETH can be used by passing the ETH sentinel value as the asset. This will deduct WETH instead, unwrap it and send
                // it to the recipient as ETH.
                //
                // Emits an `InternalBalanceChanged` event.
                //
                //
                // - TRANSFER_INTERNAL
                // Transfers tokens from the Internal Balance of the `sender` account to the Internal Balance of `recipient`.
                //
                // Reverts if the ETH sentinel value is passed.
                //
                // Emits an `InternalBalanceChanged` event.
                //
                //
                // - TRANSFER_EXTERNAL
                // Transfers tokens from `sender` to `recipient`, using the Vault's ERC20 allowance. This is typically used by
                // relayers, as it lets them reuse a user's Vault allowance.
                //
                // Reverts if the ETH sentinel value is passed.
                //
                // Emits an `ExternalBalanceTransfer` event.
                enum UserBalanceOpKind { DEPOSIT_INTERNAL, WITHDRAW_INTERNAL, TRANSFER_INTERNAL, TRANSFER_EXTERNAL }
                /**
                 * @dev Emitted when a user's Internal Balance changes, either from calls to `manageUserBalance`, or through
                 * interacting with Pools using Internal Balance.
                 *
                 * Because Internal Balance works exclusively with ERC20 tokens, ETH deposits and withdrawals will use the WETH
                 * address.
                 */
                event InternalBalanceChanged(address indexed user, IERC20 indexed token, int256 delta);
                /**
                 * @dev Emitted when a user's Vault ERC20 allowance is used by the Vault to transfer tokens to an external account.
                 */
                event ExternalBalanceTransfer(IERC20 indexed token, address indexed sender, address recipient, uint256 amount);
                // Pools
                //
                // There are three specialization settings for Pools, which allow for cheaper swaps at the cost of reduced
                // functionality:
                //
                //  - General: no specialization, suited for all Pools. IGeneralPool is used for swap request callbacks, passing the
                // balance of all tokens in the Pool. These Pools have the largest swap costs (because of the extra storage reads),
                // which increase with the number of registered tokens.
                //
                //  - Minimal Swap Info: IMinimalSwapInfoPool is used instead of IGeneralPool, which saves gas by only passing the
                // balance of the two tokens involved in the swap. This is suitable for some pricing algorithms, like the weighted
                // constant product one popularized by Balancer V1. Swap costs are smaller compared to general Pools, and are
                // independent of the number of registered tokens.
                //
                //  - Two Token: only allows two tokens to be registered. This achieves the lowest possible swap gas cost. Like
                // minimal swap info Pools, these are called via IMinimalSwapInfoPool.
                enum PoolSpecialization { GENERAL, MINIMAL_SWAP_INFO, TWO_TOKEN }
                /**
                 * @dev Registers the caller account as a Pool with a given specialization setting. Returns the Pool's ID, which
                 * is used in all Pool-related functions. Pools cannot be deregistered, nor can the Pool's specialization be
                 * changed.
                 *
                 * The caller is expected to be a smart contract that implements either `IGeneralPool` or `IMinimalSwapInfoPool`,
                 * depending on the chosen specialization setting. This contract is known as the Pool's contract.
                 *
                 * Note that the same contract may register itself as multiple Pools with unique Pool IDs, or in other words,
                 * multiple Pools may share the same contract.
                 *
                 * Emits a `PoolRegistered` event.
                 */
                function registerPool(PoolSpecialization specialization) external returns (bytes32);
                /**
                 * @dev Emitted when a Pool is registered by calling `registerPool`.
                 */
                event PoolRegistered(bytes32 indexed poolId, address indexed poolAddress, PoolSpecialization specialization);
                /**
                 * @dev Returns a Pool's contract address and specialization setting.
                 */
                function getPool(bytes32 poolId) external view returns (address, PoolSpecialization);
                /**
                 * @dev Registers `tokens` for the `poolId` Pool. Must be called by the Pool's contract.
                 *
                 * Pools can only interact with tokens they have registered. Users join a Pool by transferring registered tokens,
                 * exit by receiving registered tokens, and can only swap registered tokens.
                 *
                 * Each token can only be registered once. For Pools with the Two Token specialization, `tokens` must have a length
                 * of two, that is, both tokens must be registered in the same `registerTokens` call, and they must be sorted in
                 * ascending order.
                 *
                 * The `tokens` and `assetManagers` arrays must have the same length, and each entry in these indicates the Asset
                 * Manager for the corresponding token. Asset Managers can manage a Pool's tokens via `managePoolBalance`,
                 * depositing and withdrawing them directly, and can even set their balance to arbitrary amounts. They are therefore
                 * expected to be highly secured smart contracts with sound design principles, and the decision to register an
                 * Asset Manager should not be made lightly.
                 *
                 * Pools can choose not to assign an Asset Manager to a given token by passing in the zero address. Once an Asset
                 * Manager is set, it cannot be changed except by deregistering the associated token and registering again with a
                 * different Asset Manager.
                 *
                 * Emits a `TokensRegistered` event.
                 */
                function registerTokens(
                    bytes32 poolId,
                    IERC20[] memory tokens,
                    address[] memory assetManagers
                ) external;
                /**
                 * @dev Emitted when a Pool registers tokens by calling `registerTokens`.
                 */
                event TokensRegistered(bytes32 indexed poolId, IERC20[] tokens, address[] assetManagers);
                /**
                 * @dev Deregisters `tokens` for the `poolId` Pool. Must be called by the Pool's contract.
                 *
                 * Only registered tokens (via `registerTokens`) can be deregistered. Additionally, they must have zero total
                 * balance. For Pools with the Two Token specialization, `tokens` must have a length of two, that is, both tokens
                 * must be deregistered in the same `deregisterTokens` call.
                 *
                 * A deregistered token can be re-registered later on, possibly with a different Asset Manager.
                 *
                 * Emits a `TokensDeregistered` event.
                 */
                function deregisterTokens(bytes32 poolId, IERC20[] memory tokens) external;
                /**
                 * @dev Emitted when a Pool deregisters tokens by calling `deregisterTokens`.
                 */
                event TokensDeregistered(bytes32 indexed poolId, IERC20[] tokens);
                /**
                 * @dev Returns detailed information for a Pool's registered token.
                 *
                 * `cash` is the number of tokens the Vault currently holds for the Pool. `managed` is the number of tokens
                 * withdrawn and held outside the Vault by the Pool's token Asset Manager. The Pool's total balance for `token`
                 * equals the sum of `cash` and `managed`.
                 *
                 * Internally, `cash` and `managed` are stored using 112 bits. No action can ever cause a Pool's token `cash`,
                 * `managed` or `total` balance to be greater than 2^112 - 1.
                 *
                 * `lastChangeBlock` is the number of the block in which `token`'s total balance was last modified (via either a
                 * join, exit, swap, or Asset Manager update). This value is useful to avoid so-called 'sandwich attacks', for
                 * example when developing price oracles. A change of zero (e.g. caused by a swap with amount zero) is considered a
                 * change for this purpose, and will update `lastChangeBlock`.
                 *
                 * `assetManager` is the Pool's token Asset Manager.
                 */
                function getPoolTokenInfo(bytes32 poolId, IERC20 token)
                    external
                    view
                    returns (
                        uint256 cash,
                        uint256 managed,
                        uint256 lastChangeBlock,
                        address assetManager
                    );
                /**
                 * @dev Returns a Pool's registered tokens, the total balance for each, and the latest block when *any* of
                 * the tokens' `balances` changed.
                 *
                 * The order of the `tokens` array is the same order that will be used in `joinPool`, `exitPool`, as well as in all
                 * Pool hooks (where applicable). Calls to `registerTokens` and `deregisterTokens` may change this order.
                 *
                 * If a Pool only registers tokens once, and these are sorted in ascending order, they will be stored in the same
                 * order as passed to `registerTokens`.
                 *
                 * Total balances include both tokens held by the Vault and those withdrawn by the Pool's Asset Managers. These are
                 * the amounts used by joins, exits and swaps. For a detailed breakdown of token balances, use `getPoolTokenInfo`
                 * instead.
                 */
                function getPoolTokens(bytes32 poolId)
                    external
                    view
                    returns (
                        IERC20[] memory tokens,
                        uint256[] memory balances,
                        uint256 lastChangeBlock
                    );
                /**
                 * @dev Called by users to join a Pool, which transfers tokens from `sender` into the Pool's balance. This will
                 * trigger custom Pool behavior, which will typically grant something in return to `recipient` - often tokenized
                 * Pool shares.
                 *
                 * If the caller is not `sender`, it must be an authorized relayer for them.
                 *
                 * The `assets` and `maxAmountsIn` arrays must have the same length, and each entry indicates the maximum amount
                 * to send for each asset. The amounts to send are decided by the Pool and not the Vault: it just enforces
                 * these maximums.
                 *
                 * If joining a Pool that holds WETH, it is possible to send ETH directly: the Vault will do the wrapping. To enable
                 * this mechanism, the IAsset sentinel value (the zero address) must be passed in the `assets` array instead of the
                 * WETH address. Note that it is not possible to combine ETH and WETH in the same join. Any excess ETH will be sent
                 * back to the caller (not the sender, which is important for relayers).
                 *
                 * `assets` must have the same length and order as the array returned by `getPoolTokens`. This prevents issues when
                 * interacting with Pools that register and deregister tokens frequently. If sending ETH however, the array must be
                 * sorted *before* replacing the WETH address with the ETH sentinel value (the zero address), which means the final
                 * `assets` array might not be sorted. Pools with no registered tokens cannot be joined.
                 *
                 * If `fromInternalBalance` is true, the caller's Internal Balance will be preferred: ERC20 transfers will only
                 * be made for the difference between the requested amount and Internal Balance (if any). Note that ETH cannot be
                 * withdrawn from Internal Balance: attempting to do so will trigger a revert.
                 *
                 * This causes the Vault to call the `IBasePool.onJoinPool` hook on the Pool's contract, where Pools implement
                 * their own custom logic. This typically requires additional information from the user (such as the expected number
                 * of Pool shares). This can be encoded in the `userData` argument, which is ignored by the Vault and passed
                 * directly to the Pool's contract, as is `recipient`.
                 *
                 * Emits a `PoolBalanceChanged` event.
                 */
                function joinPool(
                    bytes32 poolId,
                    address sender,
                    address recipient,
                    JoinPoolRequest memory request
                ) external payable;
                struct JoinPoolRequest {
                    IAsset[] assets;
                    uint256[] maxAmountsIn;
                    bytes userData;
                    bool fromInternalBalance;
                }
                /**
                 * @dev Called by users to exit a Pool, which transfers tokens from the Pool's balance to `recipient`. This will
                 * trigger custom Pool behavior, which will typically ask for something in return from `sender` - often tokenized
                 * Pool shares. The amount of tokens that can be withdrawn is limited by the Pool's `cash` balance (see
                 * `getPoolTokenInfo`).
                 *
                 * If the caller is not `sender`, it must be an authorized relayer for them.
                 *
                 * The `tokens` and `minAmountsOut` arrays must have the same length, and each entry in these indicates the minimum
                 * token amount to receive for each token contract. The amounts to send are decided by the Pool and not the Vault:
                 * it just enforces these minimums.
                 *
                 * If exiting a Pool that holds WETH, it is possible to receive ETH directly: the Vault will do the unwrapping. To
                 * enable this mechanism, the IAsset sentinel value (the zero address) must be passed in the `assets` array instead
                 * of the WETH address. Note that it is not possible to combine ETH and WETH in the same exit.
                 *
                 * `assets` must have the same length and order as the array returned by `getPoolTokens`. This prevents issues when
                 * interacting with Pools that register and deregister tokens frequently. If receiving ETH however, the array must
                 * be sorted *before* replacing the WETH address with the ETH sentinel value (the zero address), which means the
                 * final `assets` array might not be sorted. Pools with no registered tokens cannot be exited.
                 *
                 * If `toInternalBalance` is true, the tokens will be deposited to `recipient`'s Internal Balance. Otherwise,
                 * an ERC20 transfer will be performed. Note that ETH cannot be deposited to Internal Balance: attempting to
                 * do so will trigger a revert.
                 *
                 * `minAmountsOut` is the minimum amount of tokens the user expects to get out of the Pool, for each token in the
                 * `tokens` array. This array must match the Pool's registered tokens.
                 *
                 * This causes the Vault to call the `IBasePool.onExitPool` hook on the Pool's contract, where Pools implement
                 * their own custom logic. This typically requires additional information from the user (such as the expected number
                 * of Pool shares to return). This can be encoded in the `userData` argument, which is ignored by the Vault and
                 * passed directly to the Pool's contract.
                 *
                 * Emits a `PoolBalanceChanged` event.
                 */
                function exitPool(
                    bytes32 poolId,
                    address sender,
                    address payable recipient,
                    ExitPoolRequest memory request
                ) external;
                struct ExitPoolRequest {
                    IAsset[] assets;
                    uint256[] minAmountsOut;
                    bytes userData;
                    bool toInternalBalance;
                }
                /**
                 * @dev Emitted when a user joins or exits a Pool by calling `joinPool` or `exitPool`, respectively.
                 */
                event PoolBalanceChanged(
                    bytes32 indexed poolId,
                    address indexed liquidityProvider,
                    IERC20[] tokens,
                    int256[] deltas,
                    uint256[] protocolFeeAmounts
                );
                enum PoolBalanceChangeKind { JOIN, EXIT }
                // Swaps
                //
                // Users can swap tokens with Pools by calling the `swap` and `batchSwap` functions. To do this,
                // they need not trust Pool contracts in any way: all security checks are made by the Vault. They must however be
                // aware of the Pools' pricing algorithms in order to estimate the prices Pools will quote.
                //
                // The `swap` function executes a single swap, while `batchSwap` can perform multiple swaps in sequence.
                // In each individual swap, tokens of one kind are sent from the sender to the Pool (this is the 'token in'),
                // and tokens of another kind are sent from the Pool to the recipient in exchange (this is the 'token out').
                // More complex swaps, such as one token in to multiple tokens out can be achieved by batching together
                // individual swaps.
                //
                // There are two swap kinds:
                //  - 'given in' swaps, where the amount of tokens in (sent to the Pool) is known, and the Pool determines (via the
                // `onSwap` hook) the amount of tokens out (to send to the recipient).
                //  - 'given out' swaps, where the amount of tokens out (received from the Pool) is known, and the Pool determines
                // (via the `onSwap` hook) the amount of tokens in (to receive from the sender).
                //
                // Additionally, it is possible to chain swaps using a placeholder input amount, which the Vault replaces with
                // the calculated output of the previous swap. If the previous swap was 'given in', this will be the calculated
                // tokenOut amount. If the previous swap was 'given out', it will use the calculated tokenIn amount. These extended
                // swaps are known as 'multihop' swaps, since they 'hop' through a number of intermediate tokens before arriving at
                // the final intended token.
                //
                // In all cases, tokens are only transferred in and out of the Vault (or withdrawn from and deposited into Internal
                // Balance) after all individual swaps have been completed, and the net token balance change computed. This makes
                // certain swap patterns, such as multihops, or swaps that interact with the same token pair in multiple Pools, cost
                // much less gas than they would otherwise.
                //
                // It also means that under certain conditions it is possible to perform arbitrage by swapping with multiple
                // Pools in a way that results in net token movement out of the Vault (profit), with no tokens being sent in (only
                // updating the Pool's internal accounting).
                //
                // To protect users from front-running or the market changing rapidly, they supply a list of 'limits' for each token
                // involved in the swap, where either the maximum number of tokens to send (by passing a positive value) or the
                // minimum amount of tokens to receive (by passing a negative value) is specified.
                //
                // Additionally, a 'deadline' timestamp can also be provided, forcing the swap to fail if it occurs after
                // this point in time (e.g. if the transaction failed to be included in a block promptly).
                //
                // If interacting with Pools that hold WETH, it is possible to both send and receive ETH directly: the Vault will do
                // the wrapping and unwrapping. To enable this mechanism, the IAsset sentinel value (the zero address) must be
                // passed in the `assets` array instead of the WETH address. Note that it is possible to combine ETH and WETH in the
                // same swap. Any excess ETH will be sent back to the caller (not the sender, which is relevant for relayers).
                //
                // Finally, Internal Balance can be used when either sending or receiving tokens.
                enum SwapKind { GIVEN_IN, GIVEN_OUT }
                /**
                 * @dev Performs a swap with a single Pool.
                 *
                 * If the swap is 'given in' (the number of tokens to send to the Pool is known), it returns the amount of tokens
                 * taken from the Pool, which must be greater than or equal to `limit`.
                 *
                 * If the swap is 'given out' (the number of tokens to take from the Pool is known), it returns the amount of tokens
                 * sent to the Pool, which must be less than or equal to `limit`.
                 *
                 * Internal Balance usage and the recipient are determined by the `funds` struct.
                 *
                 * Emits a `Swap` event.
                 */
                function swap(
                    SingleSwap memory singleSwap,
                    FundManagement memory funds,
                    uint256 limit,
                    uint256 deadline
                ) external payable returns (uint256);
                /**
                 * @dev Data for a single swap executed by `swap`. `amount` is either `amountIn` or `amountOut` depending on
                 * the `kind` value.
                 *
                 * `assetIn` and `assetOut` are either token addresses, or the IAsset sentinel value for ETH (the zero address).
                 * Note that Pools never interact with ETH directly: it will be wrapped to or unwrapped from WETH by the Vault.
                 *
                 * The `userData` field is ignored by the Vault, but forwarded to the Pool in the `onSwap` hook, and may be
                 * used to extend swap behavior.
                 */
                struct SingleSwap {
                    bytes32 poolId;
                    SwapKind kind;
                    IAsset assetIn;
                    IAsset assetOut;
                    uint256 amount;
                    bytes userData;
                }
                /**
                 * @dev Performs a series of swaps with one or multiple Pools. In each individual swap, the caller determines either
                 * the amount of tokens sent to or received from the Pool, depending on the `kind` value.
                 *
                 * Returns an array with the net Vault asset balance deltas. Positive amounts represent tokens (or ETH) sent to the
                 * Vault, and negative amounts represent tokens (or ETH) sent by the Vault. Each delta corresponds to the asset at
                 * the same index in the `assets` array.
                 *
                 * Swaps are executed sequentially, in the order specified by the `swaps` array. Each array element describes a
                 * Pool, the token to be sent to this Pool, the token to receive from it, and an amount that is either `amountIn` or
                 * `amountOut` depending on the swap kind.
                 *
                 * Multihop swaps can be executed by passing an `amount` value of zero for a swap. This will cause the amount in/out
                 * of the previous swap to be used as the amount in for the current one. In a 'given in' swap, 'tokenIn' must equal
                 * the previous swap's `tokenOut`. For a 'given out' swap, `tokenOut` must equal the previous swap's `tokenIn`.
                 *
                 * The `assets` array contains the addresses of all assets involved in the swaps. These are either token addresses,
                 * or the IAsset sentinel value for ETH (the zero address). Each entry in the `swaps` array specifies tokens in and
                 * out by referencing an index in `assets`. Note that Pools never interact with ETH directly: it will be wrapped to
                 * or unwrapped from WETH by the Vault.
                 *
                 * Internal Balance usage, sender, and recipient are determined by the `funds` struct. The `limits` array specifies
                 * the minimum or maximum amount of each token the vault is allowed to transfer.
                 *
                 * `batchSwap` can be used to make a single swap, like `swap` does, but doing so requires more gas than the
                 * equivalent `swap` call.
                 *
                 * Emits `Swap` events.
                 */
                function batchSwap(
                    SwapKind kind,
                    BatchSwapStep[] memory swaps,
                    IAsset[] memory assets,
                    FundManagement memory funds,
                    int256[] memory limits,
                    uint256 deadline
                ) external payable returns (int256[] memory);
                /**
                 * @dev Data for each individual swap executed by `batchSwap`. The asset in and out fields are indexes into the
                 * `assets` array passed to that function, and ETH assets are converted to WETH.
                 *
                 * If `amount` is zero, the multihop mechanism is used to determine the actual amount based on the amount in/out
                 * from the previous swap, depending on the swap kind.
                 *
                 * The `userData` field is ignored by the Vault, but forwarded to the Pool in the `onSwap` hook, and may be
                 * used to extend swap behavior.
                 */
                struct BatchSwapStep {
                    bytes32 poolId;
                    uint256 assetInIndex;
                    uint256 assetOutIndex;
                    uint256 amount;
                    bytes userData;
                }
                /**
                 * @dev Emitted for each individual swap performed by `swap` or `batchSwap`.
                 */
                event Swap(
                    bytes32 indexed poolId,
                    IERC20 indexed tokenIn,
                    IERC20 indexed tokenOut,
                    uint256 amountIn,
                    uint256 amountOut
                );
                /**
                 * @dev All tokens in a swap are either sent from the `sender` account to the Vault, or from the Vault to the
                 * `recipient` account.
                 *
                 * If the caller is not `sender`, it must be an authorized relayer for them.
                 *
                 * If `fromInternalBalance` is true, the `sender`'s Internal Balance will be preferred, performing an ERC20
                 * transfer for the difference between the requested amount and the User's Internal Balance (if any). The `sender`
                 * must have allowed the Vault to use their tokens via `IERC20.approve()`. This matches the behavior of
                 * `joinPool`.
                 *
                 * If `toInternalBalance` is true, tokens will be deposited to `recipient`'s internal balance instead of
                 * transferred. This matches the behavior of `exitPool`.
                 *
                 * Note that ETH cannot be deposited to or withdrawn from Internal Balance: attempting to do so will trigger a
                 * revert.
                 */
                struct FundManagement {
                    address sender;
                    bool fromInternalBalance;
                    address payable recipient;
                    bool toInternalBalance;
                }
                /**
                 * @dev Simulates a call to `batchSwap`, returning an array of Vault asset deltas. Calls to `swap` cannot be
                 * simulated directly, but an equivalent `batchSwap` call can and will yield the exact same result.
                 *
                 * Each element in the array corresponds to the asset at the same index, and indicates the number of tokens (or ETH)
                 * the Vault would take from the sender (if positive) or send to the recipient (if negative). The arguments it
                 * receives are the same that an equivalent `batchSwap` call would receive.
                 *
                 * Unlike `batchSwap`, this function performs no checks on the sender or recipient field in the `funds` struct.
                 * This makes it suitable to be called by off-chain applications via eth_call without needing to hold tokens,
                 * approve them for the Vault, or even know a user's address.
                 *
                 * Note that this function is not 'view' (due to implementation details): the client code must explicitly execute
                 * eth_call instead of eth_sendTransaction.
                 */
                function queryBatchSwap(
                    SwapKind kind,
                    BatchSwapStep[] memory swaps,
                    IAsset[] memory assets,
                    FundManagement memory funds
                ) external returns (int256[] memory assetDeltas);
                // Flash Loans
                /**
                 * @dev Performs a 'flash loan', sending tokens to `recipient`, executing the `receiveFlashLoan` hook on it,
                 * and then reverting unless the tokens plus a proportional protocol fee have been returned.
                 *
                 * The `tokens` and `amounts` arrays must have the same length, and each entry in these indicates the loan amount
                 * for each token contract. `tokens` must be sorted in ascending order.
                 *
                 * The 'userData' field is ignored by the Vault, and forwarded as-is to `recipient` as part of the
                 * `receiveFlashLoan` call.
                 *
                 * Emits `FlashLoan` events.
                 */
                function flashLoan(
                    IFlashLoanRecipient recipient,
                    IERC20[] memory tokens,
                    uint256[] memory amounts,
                    bytes memory userData
                ) external;
                /**
                 * @dev Emitted for each individual flash loan performed by `flashLoan`.
                 */
                event FlashLoan(IFlashLoanRecipient indexed recipient, IERC20 indexed token, uint256 amount, uint256 feeAmount);
                // Asset Management
                //
                // Each token registered for a Pool can be assigned an Asset Manager, which is able to freely withdraw the Pool's
                // tokens from the Vault, deposit them, or assign arbitrary values to its `managed` balance (see
                // `getPoolTokenInfo`). This makes them extremely powerful and dangerous. Even if an Asset Manager only directly
                // controls one of the tokens in a Pool, a malicious manager could set that token's balance to manipulate the
                // prices of the other tokens, and then drain the Pool with swaps. The risk of using Asset Managers is therefore
                // not constrained to the tokens they are managing, but extends to the entire Pool's holdings.
                //
                // However, a properly designed Asset Manager smart contract can be safely used for the Pool's benefit,
                // for example by lending unused tokens out for interest, or using them to participate in voting protocols.
                //
                // This concept is unrelated to the IAsset interface.
                /**
                 * @dev Performs a set of Pool balance operations, which may be either withdrawals, deposits or updates.
                 *
                 * Pool Balance management features batching, which means a single contract call can be used to perform multiple
                 * operations of different kinds, with different Pools and tokens, at once.
                 *
                 * For each operation, the caller must be registered as the Asset Manager for `token` in `poolId`.
                 */
                function managePoolBalance(PoolBalanceOp[] memory ops) external;
                struct PoolBalanceOp {
                    PoolBalanceOpKind kind;
                    bytes32 poolId;
                    IERC20 token;
                    uint256 amount;
                }
                /**
                 * Withdrawals decrease the Pool's cash, but increase its managed balance, leaving the total balance unchanged.
                 *
                 * Deposits increase the Pool's cash, but decrease its managed balance, leaving the total balance unchanged.
                 *
                 * Updates don't affect the Pool's cash balance, but because the managed balance changes, it does alter the total.
                 * The external amount can be either increased or decreased by this call (i.e., reporting a gain or a loss).
                 */
                enum PoolBalanceOpKind { WITHDRAW, DEPOSIT, UPDATE }
                /**
                 * @dev Emitted when a Pool's token Asset Manager alters its balance via `managePoolBalance`.
                 */
                event PoolBalanceManaged(
                    bytes32 indexed poolId,
                    address indexed assetManager,
                    IERC20 indexed token,
                    int256 cashDelta,
                    int256 managedDelta
                );
                // Protocol Fees
                //
                // Some operations cause the Vault to collect tokens in the form of protocol fees, which can then be withdrawn by
                // permissioned accounts.
                //
                // There are two kinds of protocol fees:
                //
                //  - flash loan fees: charged on all flash loans, as a percentage of the amounts lent.
                //
                //  - swap fees: a percentage of the fees charged by Pools when performing swaps. For a number of reasons, including
                // swap gas costs and interface simplicity, protocol swap fees are not charged on each individual swap. Rather,
                // Pools are expected to keep track of how much they have charged in swap fees, and pay any outstanding debts to the
                // Vault when they are joined or exited. This prevents users from joining a Pool with unpaid debt, as well as
                // exiting a Pool in debt without first paying their share.
                /**
                 * @dev Returns the current protocol fee module.
                 */
                function getProtocolFeesCollector() external view returns (IProtocolFeesCollector);
                /**
                 * @dev Safety mechanism to pause most Vault operations in the event of an emergency - typically detection of an
                 * error in some part of the system.
                 *
                 * The Vault can only be paused during an initial time period, after which pausing is forever disabled.
                 *
                 * While the contract is paused, the following features are disabled:
                 * - depositing and transferring internal balance
                 * - transferring external balance (using the Vault's allowance)
                 * - swaps
                 * - joining Pools
                 * - Asset Manager interactions
                 *
                 * Internal Balance can still be withdrawn, and Pools exited.
                 */
                function setPaused(bool paused) external;
                /**
                 * @dev Returns the Vault's WETH instance.
                 */
                function WETH() external view returns (IWETH);
                // solhint-disable-previous-line func-name-mixedcase
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            pragma experimental ABIEncoderV2;
            import "./IVault.sol";
            import "./IPoolSwapStructs.sol";
            /**
             * @dev Interface for adding and removing liquidity that all Pool contracts should implement. Note that this is not
             * the complete Pool contract interface, as it is missing the swap hooks. Pool contracts should also inherit from
             * either IGeneralPool or IMinimalSwapInfoPool
             */
            interface IBasePool is IPoolSwapStructs {
                /**
                 * @dev Called by the Vault when a user calls `IVault.joinPool` to add liquidity to this Pool. Returns how many of
                 * each registered token the user should provide, as well as the amount of protocol fees the Pool owes to the Vault.
                 * The Vault will then take tokens from `sender` and add them to the Pool's balances, as well as collect
                 * the reported amount in protocol fees, which the pool should calculate based on `protocolSwapFeePercentage`.
                 *
                 * Protocol fees are reported and charged on join events so that the Pool is free of debt whenever new users join.
                 *
                 * `sender` is the account performing the join (from which tokens will be withdrawn), and `recipient` is the account
                 * designated to receive any benefits (typically pool shares). `balances` contains the total balances
                 * for each token the Pool registered in the Vault, in the same order that `IVault.getPoolTokens` would return.
                 *
                 * `lastChangeBlock` is the last block in which *any* of the Pool's registered tokens last changed its total
                 * balance.
                 *
                 * `userData` contains any pool-specific instructions needed to perform the calculations, such as the type of
                 * join (e.g., proportional given an amount of pool shares, single-asset, multi-asset, etc.)
                 *
                 * Contracts implementing this function should check that the caller is indeed the Vault before performing any
                 * state-changing operations, such as minting pool shares.
                 */
                function onJoinPool(
                    bytes32 poolId,
                    address sender,
                    address recipient,
                    uint256[] memory balances,
                    uint256 lastChangeBlock,
                    uint256 protocolSwapFeePercentage,
                    bytes memory userData
                ) external returns (uint256[] memory amountsIn, uint256[] memory dueProtocolFeeAmounts);
                /**
                 * @dev Called by the Vault when a user calls `IVault.exitPool` to remove liquidity from this Pool. Returns how many
                 * tokens the Vault should deduct from the Pool's balances, as well as the amount of protocol fees the Pool owes
                 * to the Vault. The Vault will then take tokens from the Pool's balances and send them to `recipient`,
                 * as well as collect the reported amount in protocol fees, which the Pool should calculate based on
                 * `protocolSwapFeePercentage`.
                 *
                 * Protocol fees are charged on exit events to guarantee that users exiting the Pool have paid their share.
                 *
                 * `sender` is the account performing the exit (typically the pool shareholder), and `recipient` is the account
                 * to which the Vault will send the proceeds. `balances` contains the total token balances for each token
                 * the Pool registered in the Vault, in the same order that `IVault.getPoolTokens` would return.
                 *
                 * `lastChangeBlock` is the last block in which *any* of the Pool's registered tokens last changed its total
                 * balance.
                 *
                 * `userData` contains any pool-specific instructions needed to perform the calculations, such as the type of
                 * exit (e.g., proportional given an amount of pool shares, single-asset, multi-asset, etc.)
                 *
                 * Contracts implementing this function should check that the caller is indeed the Vault before performing any
                 * state-changing operations, such as burning pool shares.
                 */
                function onExitPool(
                    bytes32 poolId,
                    address sender,
                    address recipient,
                    uint256[] memory balances,
                    uint256 lastChangeBlock,
                    uint256 protocolSwapFeePercentage,
                    bytes memory userData
                ) external returns (uint256[] memory amountsOut, uint256[] memory dueProtocolFeeAmounts);
                function getPoolId() external view returns (bytes32);
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            pragma experimental ABIEncoderV2;
            import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/IERC20.sol";
            interface IAssetManager {
                /**
                 * @notice Emitted when asset manager is rebalanced
                 */
                event Rebalance(bytes32 poolId);
                /**
                 * @notice Sets the config
                 */
                function setConfig(bytes32 poolId, bytes calldata config) external;
                /**
                 * Note: No function to read the asset manager config is included in IAssetManager
                 * as the signature is expected to vary between asset manager implementations
                 */
                /**
                 * @notice Returns the asset manager's token
                 */
                function getToken() external view returns (IERC20);
                /**
                 * @return the current assets under management of this asset manager
                 */
                function getAUM(bytes32 poolId) external view returns (uint256);
                /**
                 * @return poolCash - The up-to-date cash balance of the pool
                 * @return poolManaged - The up-to-date managed balance of the pool
                 */
                function getPoolBalances(bytes32 poolId) external view returns (uint256 poolCash, uint256 poolManaged);
                /**
                 * @return The difference in tokens between the target investment
                 * and the currently invested amount (i.e. the amount that can be invested)
                 */
                function maxInvestableBalance(bytes32 poolId) external view returns (int256);
                /**
                 * @notice Updates the Vault on the value of the pool's investment returns
                 */
                function updateBalanceOfPool(bytes32 poolId) external;
                /**
                 * @notice Determines whether the pool should rebalance given the provided balances
                 */
                function shouldRebalance(uint256 cash, uint256 managed) external view returns (bool);
                /**
                 * @notice Rebalances funds between the pool and the asset manager to maintain target investment percentage.
                 * @param poolId - the poolId of the pool to be rebalanced
                 * @param force - a boolean representing whether a rebalance should be forced even when the pool is near balance
                 */
                function rebalance(bytes32 poolId, bool force) external;
                /**
                 * @notice allows an authorized rebalancer to remove capital to facilitate large withdrawals
                 * @param poolId - the poolId of the pool to withdraw funds back to
                 * @param amount - the amount of tokens to withdraw back to the pool
                 */
                function capitalOut(bytes32 poolId, uint256 amount) external;
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/ERC20.sol";
            import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/ERC20Permit.sol";
            /**
             * @title Highly opinionated token implementation
             * @author Balancer Labs
             * @dev
             * - Includes functions to increase and decrease allowance as a workaround
             *   for the well-known issue with `approve`:
             *   https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
             * - Allows for 'infinite allowance', where an allowance of 0xff..ff is not
             *   decreased by calls to transferFrom
             * - Lets a token holder use `transferFrom` to send their own tokens,
             *   without first setting allowance
             * - Emits 'Approval' events whenever allowance is changed by `transferFrom`
             */
            contract BalancerPoolToken is ERC20, ERC20Permit {
                constructor(string memory tokenName, string memory tokenSymbol)
                    ERC20(tokenName, tokenSymbol)
                    ERC20Permit(tokenName)
                {
                    // solhint-disable-previous-line no-empty-blocks
                }
                // Overrides
                /**
                 * @dev Override to allow for 'infinite allowance' and let the token owner use `transferFrom` with no self-allowance
                 */
                function transferFrom(
                    address sender,
                    address recipient,
                    uint256 amount
                ) public override returns (bool) {
                    uint256 currentAllowance = allowance(sender, msg.sender);
                    _require(msg.sender == sender || currentAllowance >= amount, Errors.ERC20_TRANSFER_EXCEEDS_ALLOWANCE);
                    _transfer(sender, recipient, amount);
                    if (msg.sender != sender && currentAllowance != uint256(-1)) {
                        // Because of the previous require, we know that if msg.sender != sender then currentAllowance >= amount
                        _approve(sender, msg.sender, currentAllowance - amount);
                    }
                    return true;
                }
                /**
                 * @dev Override to allow decreasing allowance by more than the current amount (setting it to zero)
                 */
                function decreaseAllowance(address spender, uint256 amount) public override returns (bool) {
                    uint256 currentAllowance = allowance(msg.sender, spender);
                    if (amount >= currentAllowance) {
                        _approve(msg.sender, spender, 0);
                    } else {
                        // No risk of underflow due to if condition
                        _approve(msg.sender, spender, currentAllowance - amount);
                    }
                    return true;
                }
                // Internal functions
                function _mintPoolTokens(address recipient, uint256 amount) internal {
                    _mint(recipient, amount);
                }
                function _burnPoolTokens(address sender, uint256 amount) internal {
                    _burn(sender, amount);
                }
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            import "@balancer-labs/v2-solidity-utils/contracts/helpers/Authentication.sol";
            import "@balancer-labs/v2-vault/contracts/interfaces/IAuthorizer.sol";
            import "./BasePool.sol";
            /**
             * @dev Base authorization layer implementation for Pools.
             *
             * The owner account can call some of the permissioned functions - access control of the rest is delegated to the
             * Authorizer. Note that this owner is immutable: more sophisticated permission schemes, such as multiple ownership,
             * granular roles, etc., could be built on top of this by making the owner a smart contract.
             *
             * Access control of all other permissioned functions is delegated to an Authorizer. It is also possible to delegate
             * control of *all* permissioned functions to the Authorizer by setting the owner address to `_DELEGATE_OWNER`.
             */
            abstract contract BasePoolAuthorization is Authentication {
                address private immutable _owner;
                address private constant _DELEGATE_OWNER = 0xBA1BA1ba1BA1bA1bA1Ba1BA1ba1BA1bA1ba1ba1B;
                constructor(address owner) {
                    _owner = owner;
                }
                function getOwner() public view returns (address) {
                    return _owner;
                }
                function getAuthorizer() external view returns (IAuthorizer) {
                    return _getAuthorizer();
                }
                function _canPerform(bytes32 actionId, address account) internal view override returns (bool) {
                    if ((getOwner() != _DELEGATE_OWNER) && _isOwnerOnlyAction(actionId)) {
                        // Only the owner can perform "owner only" actions, unless the owner is delegated.
                        return msg.sender == getOwner();
                    } else {
                        // Non-owner actions are always processed via the Authorizer, as "owner only" ones are when delegated.
                        return _getAuthorizer().canPerform(actionId, account, address(this));
                    }
                }
                function _isOwnerOnlyAction(bytes32 actionId) internal view virtual returns (bool);
                function _getAuthorizer() internal view virtual returns (IAuthorizer);
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            /**
             * @dev Interface for the TemporarilyPausable helper.
             */
            interface ITemporarilyPausable {
                /**
                 * @dev Emitted every time the pause state changes by `_setPaused`.
                 */
                event PausedStateChanged(bool paused);
                /**
                 * @dev Returns the current paused state.
                 */
                function getPausedState()
                    external
                    view
                    returns (
                        bool paused,
                        uint256 pauseWindowEndTime,
                        uint256 bufferPeriodEndTime
                    );
            }
            // SPDX-License-Identifier: MIT
            pragma solidity ^0.7.0;
            import "../helpers/BalancerErrors.sol";
            /**
             * @dev Wrappers over Solidity's arithmetic operations with added overflow
             * checks.
             *
             * Arithmetic operations in Solidity wrap on overflow. This can easily result
             * in bugs, because programmers usually assume that an overflow raises an
             * error, which is the standard behavior in high level programming languages.
             * `SafeMath` restores this intuition by reverting the transaction when an
             * operation overflows.
             *
             * Using this library instead of the unchecked operations eliminates an entire
             * class of bugs, so it's recommended to use it always.
             */
            library SafeMath {
                /**
                 * @dev Returns the addition of two unsigned integers, reverting on
                 * overflow.
                 *
                 * Counterpart to Solidity's `+` operator.
                 *
                 * Requirements:
                 *
                 * - Addition cannot overflow.
                 */
                function add(uint256 a, uint256 b) internal pure returns (uint256) {
                    uint256 c = a + b;
                    _require(c >= a, Errors.ADD_OVERFLOW);
                    return c;
                }
                /**
                 * @dev Returns the subtraction of two unsigned integers, reverting on
                 * overflow (when the result is negative).
                 *
                 * Counterpart to Solidity's `-` operator.
                 *
                 * Requirements:
                 *
                 * - Subtraction cannot overflow.
                 */
                function sub(uint256 a, uint256 b) internal pure returns (uint256) {
                    return sub(a, b, Errors.SUB_OVERFLOW);
                }
                /**
                 * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
                 * overflow (when the result is negative).
                 *
                 * Counterpart to Solidity's `-` operator.
                 *
                 * Requirements:
                 *
                 * - Subtraction cannot overflow.
                 */
                function sub(uint256 a, uint256 b, uint256 errorCode) internal pure returns (uint256) {
                    _require(b <= a, errorCode);
                    uint256 c = a - b;
                    return c;
                }
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            /**
             * @dev Interface for the SignatureValidator helper, used to support meta-transactions.
             */
            interface ISignaturesValidator {
                /**
                 * @dev Returns the EIP712 domain separator.
                 */
                function getDomainSeparator() external view returns (bytes32);
                /**
                 * @dev Returns the next nonce used by an address to sign messages.
                 */
                function getNextNonce(address user) external view returns (uint256);
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            import "../openzeppelin/IERC20.sol";
            /**
             * @dev Interface for WETH9.
             * See https://github.com/gnosis/canonical-weth/blob/0dd1ea3e295eef916d0c6223ec63141137d22d67/contracts/WETH9.sol
             */
            interface IWETH is IERC20 {
                function deposit() external payable;
                function withdraw(uint256 amount) external;
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            /**
             * @dev This is an empty interface used to represent either ERC20-conforming token contracts or ETH (using the zero
             * address sentinel value). We're just relying on the fact that `interface` can be used to declare new address-like
             * types.
             *
             * This concept is unrelated to a Pool's Asset Managers.
             */
            interface IAsset {
                // solhint-disable-previous-line no-empty-blocks
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            interface IAuthorizer {
                /**
                 * @dev Returns true if `account` can perform the action described by `actionId` in the contract `where`.
                 */
                function canPerform(
                    bytes32 actionId,
                    address account,
                    address where
                ) external view returns (bool);
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            // Inspired by Aave Protocol's IFlashLoanReceiver.
            import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/IERC20.sol";
            interface IFlashLoanRecipient {
                /**
                 * @dev When `flashLoan` is called on the Vault, it invokes the `receiveFlashLoan` hook on the recipient.
                 *
                 * At the time of the call, the Vault will have transferred `amounts` for `tokens` to the recipient. Before this
                 * call returns, the recipient must have transferred `amounts` plus `feeAmounts` for each token back to the
                 * Vault, or else the entire flash loan will revert.
                 *
                 * `userData` is the same value passed in the `IVault.flashLoan` call.
                 */
                function receiveFlashLoan(
                    IERC20[] memory tokens,
                    uint256[] memory amounts,
                    uint256[] memory feeAmounts,
                    bytes memory userData
                ) external;
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            pragma experimental ABIEncoderV2;
            import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/IERC20.sol";
            import "./IVault.sol";
            import "./IAuthorizer.sol";
            interface IProtocolFeesCollector {
                event SwapFeePercentageChanged(uint256 newSwapFeePercentage);
                event FlashLoanFeePercentageChanged(uint256 newFlashLoanFeePercentage);
                function withdrawCollectedFees(
                    IERC20[] calldata tokens,
                    uint256[] calldata amounts,
                    address recipient
                ) external;
                function setSwapFeePercentage(uint256 newSwapFeePercentage) external;
                function setFlashLoanFeePercentage(uint256 newFlashLoanFeePercentage) external;
                function getSwapFeePercentage() external view returns (uint256);
                function getFlashLoanFeePercentage() external view returns (uint256);
                function getCollectedFeeAmounts(IERC20[] memory tokens) external view returns (uint256[] memory feeAmounts);
                function getAuthorizer() external view returns (IAuthorizer);
                function vault() external view returns (IVault);
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            pragma experimental ABIEncoderV2;
            import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/IERC20.sol";
            import "./IVault.sol";
            interface IPoolSwapStructs {
                // This is not really an interface - it just defines common structs used by other interfaces: IGeneralPool and
                // IMinimalSwapInfoPool.
                //
                // This data structure represents a request for a token swap, where `kind` indicates the swap type ('given in' or
                // 'given out') which indicates whether or not the amount sent by the pool is known.
                //
                // The pool receives `tokenIn` and sends `tokenOut`. `amount` is the number of `tokenIn` tokens the pool will take
                // in, or the number of `tokenOut` tokens the Pool will send out, depending on the given swap `kind`.
                //
                // All other fields are not strictly necessary for most swaps, but are provided to support advanced scenarios in
                // some Pools.
                //
                // `poolId` is the ID of the Pool involved in the swap - this is useful for Pool contracts that implement more than
                // one Pool.
                //
                // The meaning of `lastChangeBlock` depends on the Pool specialization:
                //  - Two Token or Minimal Swap Info: the last block in which either `tokenIn` or `tokenOut` changed its total
                //    balance.
                //  - General: the last block in which *any* of the Pool's registered tokens changed its total balance.
                //
                // `from` is the origin address for the funds the Pool receives, and `to` is the destination address
                // where the Pool sends the outgoing tokens.
                //
                // `userData` is extra data provided by the caller - typically a signature from a trusted party.
                struct SwapRequest {
                    IVault.SwapKind kind;
                    IERC20 tokenIn;
                    IERC20 tokenOut;
                    uint256 amount;
                    // Misc data
                    bytes32 poolId;
                    uint256 lastChangeBlock;
                    address from;
                    address to;
                    bytes userData;
                }
            }
            // SPDX-License-Identifier: MIT
            pragma solidity ^0.7.0;
            import "./ERC20.sol";
            import "./IERC20Permit.sol";
            import "./EIP712.sol";
            /**
             * @dev Implementation of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
             * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
             *
             * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
             * presenting a message signed by the account. By not relying on `{IERC20-approve}`, the token holder account doesn't
             * need to send a transaction, and thus is not required to hold Ether at all.
             *
             * _Available since v3.4._
             */
            abstract contract ERC20Permit is ERC20, IERC20Permit, EIP712 {
                mapping(address => uint256) private _nonces;
                // solhint-disable-next-line var-name-mixedcase
                bytes32 private immutable _PERMIT_TYPEHASH =
                    keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)");
                /**
                 * @dev Initializes the {EIP712} domain separator using the `name` parameter, and setting `version` to `"1"`.
                 *
                 * It's a good idea to use the same `name` that is defined as the ERC20 token name.
                 */
                constructor(string memory name) EIP712(name, "1") {}
                /**
                 * @dev See {IERC20Permit-permit}.
                 */
                function permit(
                    address owner,
                    address spender,
                    uint256 value,
                    uint256 deadline,
                    uint8 v,
                    bytes32 r,
                    bytes32 s
                ) public virtual override {
                    // solhint-disable-next-line not-rely-on-time
                    _require(block.timestamp <= deadline, Errors.EXPIRED_PERMIT);
                    uint256 nonce = _nonces[owner];
                    bytes32 structHash = keccak256(abi.encode(_PERMIT_TYPEHASH, owner, spender, value, nonce, deadline));
                    bytes32 hash = _hashTypedDataV4(structHash);
                    address signer = ecrecover(hash, v, r, s);
                    _require((signer != address(0)) && (signer == owner), Errors.INVALID_SIGNATURE);
                    _nonces[owner] = nonce + 1;
                    _approve(owner, spender, value);
                }
                /**
                 * @dev See {IERC20Permit-nonces}.
                 */
                function nonces(address owner) public view override returns (uint256) {
                    return _nonces[owner];
                }
                /**
                 * @dev See {IERC20Permit-DOMAIN_SEPARATOR}.
                 */
                // solhint-disable-next-line func-name-mixedcase
                function DOMAIN_SEPARATOR() external view override returns (bytes32) {
                    return _domainSeparatorV4();
                }
            }
            // SPDX-License-Identifier: MIT
            pragma solidity ^0.7.0;
            /**
             * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
             * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
             *
             * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
             * presenting a message signed by the account. By not relying on `{IERC20-approve}`, the token holder account doesn't
             * need to send a transaction, and thus is not required to hold Ether at all.
             */
            interface IERC20Permit {
                /**
                 * @dev Sets `value` as the allowance of `spender` over `owner`'s tokens,
                 * given `owner`'s signed approval.
                 *
                 * IMPORTANT: The same issues {IERC20-approve} has related to transaction
                 * ordering also apply here.
                 *
                 * Emits an {Approval} event.
                 *
                 * Requirements:
                 *
                 * - `spender` cannot be the zero address.
                 * - `deadline` must be a timestamp in the future.
                 * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
                 * over the EIP712-formatted function arguments.
                 * - the signature must use ``owner``'s current nonce (see {nonces}).
                 *
                 * For more information on the signature format, see the
                 * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
                 * section].
                 */
                function permit(
                    address owner,
                    address spender,
                    uint256 value,
                    uint256 deadline,
                    uint8 v,
                    bytes32 r,
                    bytes32 s
                ) external;
                /**
                 * @dev Returns the current nonce for `owner`. This value must be
                 * included whenever a signature is generated for {permit}.
                 *
                 * Every successful call to {permit} increases ``owner``'s nonce by one. This
                 * prevents a signature from being used multiple times.
                 */
                function nonces(address owner) external view returns (uint256);
                /**
                 * @dev Returns the domain separator used in the encoding of the signature for `permit`, as defined by {EIP712}.
                 */
                // solhint-disable-next-line func-name-mixedcase
                function DOMAIN_SEPARATOR() external view returns (bytes32);
            }
            // SPDX-License-Identifier: MIT
            pragma solidity ^0.7.0;
            /**
             * @dev https://eips.ethereum.org/EIPS/eip-712[EIP 712] is a standard for hashing and signing of typed structured data.
             *
             * The encoding specified in the EIP is very generic, and such a generic implementation in Solidity is not feasible,
             * thus this contract does not implement the encoding itself. Protocols need to implement the type-specific encoding
             * they need in their contracts using a combination of `abi.encode` and `keccak256`.
             *
             * This contract implements the EIP 712 domain separator ({_domainSeparatorV4}) that is used as part of the encoding
             * scheme, and the final step of the encoding to obtain the message digest that is then signed via ECDSA
             * ({_hashTypedDataV4}).
             *
             * The implementation of the domain separator was designed to be as efficient as possible while still properly updating
             * the chain id to protect against replay attacks on an eventual fork of the chain.
             *
             * NOTE: This contract implements the version of the encoding known as "v4", as implemented by the JSON RPC method
             * https://docs.metamask.io/guide/signing-data.html[`eth_signTypedDataV4` in MetaMask].
             *
             * _Available since v3.4._
             */
            abstract contract EIP712 {
                /* solhint-disable var-name-mixedcase */
                bytes32 private immutable _HASHED_NAME;
                bytes32 private immutable _HASHED_VERSION;
                bytes32 private immutable _TYPE_HASH;
                /* solhint-enable var-name-mixedcase */
                /**
                 * @dev Initializes the domain separator and parameter caches.
                 *
                 * The meaning of `name` and `version` is specified in
                 * https://eips.ethereum.org/EIPS/eip-712#definition-of-domainseparator[EIP 712]:
                 *
                 * - `name`: the user readable name of the signing domain, i.e. the name of the DApp or the protocol.
                 * - `version`: the current major version of the signing domain.
                 *
                 * NOTE: These parameters cannot be changed except through a xref:learn::upgrading-smart-contracts.adoc[smart
                 * contract upgrade].
                 */
                constructor(string memory name, string memory version) {
                    _HASHED_NAME = keccak256(bytes(name));
                    _HASHED_VERSION = keccak256(bytes(version));
                    _TYPE_HASH = keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)");
                }
                /**
                 * @dev Returns the domain separator for the current chain.
                 */
                function _domainSeparatorV4() internal view virtual returns (bytes32) {
                    return keccak256(abi.encode(_TYPE_HASH, _HASHED_NAME, _HASHED_VERSION, _getChainId(), address(this)));
                }
                /**
                 * @dev Given an already https://eips.ethereum.org/EIPS/eip-712#definition-of-hashstruct[hashed struct], this
                 * function returns the hash of the fully encoded EIP712 message for this domain.
                 *
                 * This hash can be used together with {ECDSA-recover} to obtain the signer of a message. For example:
                 *
                 * ```solidity
                 * bytes32 digest = _hashTypedDataV4(keccak256(abi.encode(
                 *     keccak256("Mail(address to,string contents)"),
                 *     mailTo,
                 *     keccak256(bytes(mailContents))
                 * )));
                 * address signer = ECDSA.recover(digest, signature);
                 * ```
                 */
                function _hashTypedDataV4(bytes32 structHash) internal view virtual returns (bytes32) {
                    return keccak256(abi.encodePacked("\\x19\\x01", _domainSeparatorV4(), structHash));
                }
                function _getChainId() private view returns (uint256 chainId) {
                    // Silence state mutability warning without generating bytecode.
                    // See https://github.com/ethereum/solidity/issues/10090#issuecomment-741789128 and
                    // https://github.com/ethereum/solidity/issues/2691
                    this;
                    // solhint-disable-next-line no-inline-assembly
                    assembly {
                        chainId := chainid()
                    }
                }
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            import "./BalancerErrors.sol";
            import "./IAuthentication.sol";
            /**
             * @dev Building block for performing access control on external functions.
             *
             * This contract is used via the `authenticate` modifier (or the `_authenticateCaller` function), which can be applied
             * to external functions to only make them callable by authorized accounts.
             *
             * Derived contracts must implement the `_canPerform` function, which holds the actual access control logic.
             */
            abstract contract Authentication is IAuthentication {
                bytes32 private immutable _actionIdDisambiguator;
                /**
                 * @dev The main purpose of the `actionIdDisambiguator` is to prevent accidental function selector collisions in
                 * multi contract systems.
                 *
                 * There are two main uses for it:
                 *  - if the contract is a singleton, any unique identifier can be used to make the associated action identifiers
                 *    unique. The contract's own address is a good option.
                 *  - if the contract belongs to a family that shares action identifiers for the same functions, an identifier
                 *    shared by the entire family (and no other contract) should be used instead.
                 */
                constructor(bytes32 actionIdDisambiguator) {
                    _actionIdDisambiguator = actionIdDisambiguator;
                }
                /**
                 * @dev Reverts unless the caller is allowed to call this function. Should only be applied to external functions.
                 */
                modifier authenticate() {
                    _authenticateCaller();
                    _;
                }
                /**
                 * @dev Reverts unless the caller is allowed to call the entry point function.
                 */
                function _authenticateCaller() internal view {
                    bytes32 actionId = getActionId(msg.sig);
                    _require(_canPerform(actionId, msg.sender), Errors.SENDER_NOT_ALLOWED);
                }
                function getActionId(bytes4 selector) public view override returns (bytes32) {
                    // Each external function is dynamically assigned an action identifier as the hash of the disambiguator and the
                    // function selector. Disambiguation is necessary to avoid potential collisions in the function selectors of
                    // multiple contracts.
                    return keccak256(abi.encodePacked(_actionIdDisambiguator, selector));
                }
                function _canPerform(bytes32 actionId, address user) internal view virtual returns (bool);
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            interface IAuthentication {
                /**
                 * @dev Returns the action identifier associated with the external function described by `selector`.
                 */
                function getActionId(bytes4 selector) external view returns (bytes32);
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            pragma experimental ABIEncoderV2;
            import "./LiquidityBootstrappingPool.sol";
            /**
             * @dev The original Liquidity Bootstrapping Pool computes accumulated swap fees from invariant growth, which
             * incorrectly assumes that the token weights do not change. This version is an exact copy of that flawed contract, with
             * a hotfix that hard-codes the protocol fee swap percentage to 0, ignoring the value stored in the Fee Collector.
             */
            contract NoProtocolFeeLiquidityBootstrappingPool is LiquidityBootstrappingPool {
                constructor(
                    IVault vault,
                    string memory name,
                    string memory symbol,
                    IERC20[] memory tokens,
                    uint256[] memory normalizedWeights,
                    uint256 swapFeePercentage,
                    uint256 pauseWindowDuration,
                    uint256 bufferPeriodDuration,
                    address owner,
                    bool swapEnabledOnStart
                )
                    LiquidityBootstrappingPool(
                        vault,
                        name,
                        symbol,
                        tokens,
                        normalizedWeights,
                        swapFeePercentage,
                        pauseWindowDuration,
                        bufferPeriodDuration,
                        owner,
                        swapEnabledOnStart
                    )
                {
                    // solhint-disable-previous-line no-empty-blocks
                }
                function onJoinPool(
                    bytes32 poolId,
                    address sender,
                    address recipient,
                    uint256[] memory balances,
                    uint256 lastChangeBlock,
                    uint256,
                    bytes memory userData
                ) public virtual override returns (uint256[] memory, uint256[] memory) {
                    return super.onJoinPool(poolId, sender, recipient, balances, lastChangeBlock, 0, userData);
                }
                function onExitPool(
                    bytes32 poolId,
                    address sender,
                    address recipient,
                    uint256[] memory balances,
                    uint256 lastChangeBlock,
                    uint256,
                    bytes memory userData
                ) public virtual override returns (uint256[] memory, uint256[] memory) {
                    return super.onExitPool(poolId, sender, recipient, balances, lastChangeBlock, 0, userData);
                }
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            pragma experimental ABIEncoderV2;
            import "@balancer-labs/v2-solidity-utils/contracts/openzeppelin/ReentrancyGuard.sol";
            import "@balancer-labs/v2-solidity-utils/contracts/helpers/WordCodec.sol";
            import "@balancer-labs/v2-solidity-utils/contracts/math/Math.sol";
            import "../BaseWeightedPool.sol";
            import "./WeightCompression.sol";
            /**
             * @dev Weighted Pool with mutable weights, designed to support V2 Liquidity Bootstrapping
             */
            contract LiquidityBootstrappingPool is BaseWeightedPool, ReentrancyGuard {
                // The Pause Window and Buffer Period are timestamp-based: they should not be relied upon for sub-minute accuracy.
                // solhint-disable not-rely-on-time
                using FixedPoint for uint256;
                using WordCodec for bytes32;
                using WeightCompression for uint256;
                // LBPs often involve only two tokens - we support up to four since we're able to pack the entire config in a single
                // storage slot.
                uint256 private constant _MAX_LBP_TOKENS = 4;
                // State variables
                uint256 private immutable _totalTokens;
                IERC20 internal immutable _token0;
                IERC20 internal immutable _token1;
                IERC20 internal immutable _token2;
                IERC20 internal immutable _token3;
                // All token balances are normalized to behave as if the token had 18 decimals. We assume a token's decimals will
                // not change throughout its lifetime, and store the corresponding scaling factor for each at construction time.
                // These factors are always greater than or equal to one: tokens with more than 18 decimals are not supported.
                uint256 internal immutable _scalingFactor0;
                uint256 internal immutable _scalingFactor1;
                uint256 internal immutable _scalingFactor2;
                uint256 internal immutable _scalingFactor3;
                // For gas optimization, store start/end weights and timestamps in one bytes32
                // Start weights need to be high precision, since restarting the update resets them to "spot"
                // values. Target end weights do not need as much precision.
                // [     32 bits   |     32 bits     |      64 bits     |      124 bits      |    3 bits    |     1 bit    ]
                // [ end timestamp | start timestamp | 4x16 end weights | 4x31 start weights |   not used   | swap enabled ]
                // |MSB                                                                                                 LSB|
                bytes32 private _poolState;
                // Offsets for data elements in _poolState
                uint256 private constant _SWAP_ENABLED_OFFSET = 0;
                uint256 private constant _START_WEIGHT_OFFSET = 4;
                uint256 private constant _END_WEIGHT_OFFSET = 128;
                uint256 private constant _START_TIME_OFFSET = 192;
                uint256 private constant _END_TIME_OFFSET = 224;
                // Event declarations
                event SwapEnabledSet(bool swapEnabled);
                event GradualWeightUpdateScheduled(
                    uint256 startTime,
                    uint256 endTime,
                    uint256[] startWeights,
                    uint256[] endWeights
                );
                constructor(
                    IVault vault,
                    string memory name,
                    string memory symbol,
                    IERC20[] memory tokens,
                    uint256[] memory normalizedWeights,
                    uint256 swapFeePercentage,
                    uint256 pauseWindowDuration,
                    uint256 bufferPeriodDuration,
                    address owner,
                    bool swapEnabledOnStart
                )
                    BaseWeightedPool(
                        vault,
                        name,
                        symbol,
                        tokens,
                        new address[](tokens.length), // Pass the zero address: LBPs can't have asset managers
                        swapFeePercentage,
                        pauseWindowDuration,
                        bufferPeriodDuration,
                        owner
                    )
                {
                    uint256 totalTokens = tokens.length;
                    InputHelpers.ensureInputLengthMatch(totalTokens, normalizedWeights.length);
                    _totalTokens = totalTokens;
                    // Immutable variables cannot be initialized inside an if statement, so we must do conditional assignments
                    _token0 = tokens[0];
                    _token1 = tokens[1];
                    _token2 = totalTokens > 2 ? tokens[2] : IERC20(0);
                    _token3 = totalTokens > 3 ? tokens[3] : IERC20(0);
                    _scalingFactor0 = _computeScalingFactor(tokens[0]);
                    _scalingFactor1 = _computeScalingFactor(tokens[1]);
                    _scalingFactor2 = totalTokens > 2 ? _computeScalingFactor(tokens[2]) : 0;
                    _scalingFactor3 = totalTokens > 3 ? _computeScalingFactor(tokens[3]) : 0;
                    uint256 currentTime = block.timestamp;
                    _startGradualWeightChange(currentTime, currentTime, normalizedWeights, normalizedWeights);
                    // If false, the pool will start in the disabled state (prevents front-running the enable swaps transaction)
                    _setSwapEnabled(swapEnabledOnStart);
                }
                // External functions
                /**
                 * @dev Tells whether swaps are enabled or not for the given pool.
                 */
                function getSwapEnabled() public view returns (bool) {
                    return _poolState.decodeBool(_SWAP_ENABLED_OFFSET);
                }
                /**
                 * @dev Return start time, end time, and endWeights as an array.
                 * Current weights should be retrieved via `getNormalizedWeights()`.
                 */
                function getGradualWeightUpdateParams()
                    external
                    view
                    returns (
                        uint256 startTime,
                        uint256 endTime,
                        uint256[] memory endWeights
                    )
                {
                    // Load current pool state from storage
                    bytes32 poolState = _poolState;
                    startTime = poolState.decodeUint32(_START_TIME_OFFSET);
                    endTime = poolState.decodeUint32(_END_TIME_OFFSET);
                    uint256 totalTokens = _getTotalTokens();
                    endWeights = new uint256[](totalTokens);
                    for (uint256 i = 0; i < totalTokens; i++) {
                        endWeights[i] = poolState.decodeUint16(_END_WEIGHT_OFFSET + i * 16).uncompress16();
                    }
                }
                /**
                 * @dev Can pause/unpause trading
                 */
                function setSwapEnabled(bool swapEnabled) external authenticate whenNotPaused nonReentrant {
                    _setSwapEnabled(swapEnabled);
                }
                /**
                 * @dev Schedule a gradual weight change, from the current weights to the given endWeights,
                 * over startTime to endTime
                 */
                function updateWeightsGradually(
                    uint256 startTime,
                    uint256 endTime,
                    uint256[] memory endWeights
                ) external authenticate whenNotPaused nonReentrant {
                    InputHelpers.ensureInputLengthMatch(_getTotalTokens(), endWeights.length);
                    // If the start time is in the past, "fast forward" to start now
                    // This avoids discontinuities in the weight curve. Otherwise, if you set the start/end times with
                    // only 10% of the period in the future, the weights would immediately jump 90%
                    uint256 currentTime = block.timestamp;
                    startTime = Math.max(currentTime, startTime);
                    _require(startTime <= endTime, Errors.GRADUAL_UPDATE_TIME_TRAVEL);
                    _startGradualWeightChange(startTime, endTime, _getNormalizedWeights(), endWeights);
                }
                // Internal functions
                function _getNormalizedWeight(IERC20 token) internal view override returns (uint256) {
                    uint256 i;
                    // First, convert token address to a token index
                    // prettier-ignore
                    if (token == _token0) { i = 0; }
                    else if (token == _token1) { i = 1; }
                    else if (token == _token2) { i = 2; }
                    else if (token == _token3) { i = 3; }
                    else {
                        _revert(Errors.INVALID_TOKEN);
                    }
                    return _getNormalizedWeightByIndex(i, _poolState);
                }
                function _getNormalizedWeightByIndex(uint256 i, bytes32 poolState) internal view returns (uint256) {
                    uint256 startWeight = poolState.decodeUint31(_START_WEIGHT_OFFSET + i * 31).uncompress31();
                    uint256 endWeight = poolState.decodeUint16(_END_WEIGHT_OFFSET + i * 16).uncompress16();
                    uint256 pctProgress = _calculateWeightChangeProgress(poolState);
                    return _interpolateWeight(startWeight, endWeight, pctProgress);
                }
                function _getNormalizedWeights() internal view override returns (uint256[] memory) {
                    uint256 totalTokens = _getTotalTokens();
                    uint256[] memory normalizedWeights = new uint256[](totalTokens);
                    bytes32 poolState = _poolState;
                    // prettier-ignore
                    {
                        normalizedWeights[0] = _getNormalizedWeightByIndex(0, poolState);
                        normalizedWeights[1] = _getNormalizedWeightByIndex(1, poolState);
                        if (totalTokens == 2) return normalizedWeights;
                        normalizedWeights[2] = _getNormalizedWeightByIndex(2, poolState);
                        if (totalTokens == 3) return normalizedWeights;
                        normalizedWeights[3] = _getNormalizedWeightByIndex(3, poolState);
                    }
                    return normalizedWeights;
                }
                function _getNormalizedWeightsAndMaxWeightIndex()
                    internal
                    view
                    override
                    returns (uint256[] memory normalizedWeights, uint256 maxWeightTokenIndex)
                {
                    normalizedWeights = _getNormalizedWeights();
                    maxWeightTokenIndex = 0;
                    uint256 maxNormalizedWeight = normalizedWeights[0];
                    for (uint256 i = 1; i < normalizedWeights.length; i++) {
                        if (normalizedWeights[i] > maxNormalizedWeight) {
                            maxWeightTokenIndex = i;
                            maxNormalizedWeight = normalizedWeights[i];
                        }
                    }
                }
                // Pool callback functions
                // Prevent any account other than the owner from joining the pool
                function _onInitializePool(
                    bytes32 poolId,
                    address sender,
                    address recipient,
                    uint256[] memory scalingFactors,
                    bytes memory userData
                ) internal override returns (uint256, uint256[] memory) {
                    // Only the owner can initialize the pool
                    _require(sender == getOwner(), Errors.CALLER_IS_NOT_LBP_OWNER);
                    return super._onInitializePool(poolId, sender, recipient, scalingFactors, userData);
                }
                function _onJoinPool(
                    bytes32 poolId,
                    address sender,
                    address recipient,
                    uint256[] memory balances,
                    uint256 lastChangeBlock,
                    uint256 protocolSwapFeePercentage,
                    uint256[] memory scalingFactors,
                    bytes memory userData
                )
                    internal
                    override
                    returns (
                        uint256,
                        uint256[] memory,
                        uint256[] memory
                    )
                {
                    // Only the owner can add liquidity; block public LPs
                    _require(sender == getOwner(), Errors.CALLER_IS_NOT_LBP_OWNER);
                    return
                        super._onJoinPool(
                            poolId,
                            sender,
                            recipient,
                            balances,
                            lastChangeBlock,
                            protocolSwapFeePercentage,
                            scalingFactors,
                            userData
                        );
                }
                // Swap overrides - revert unless swaps are enabled
                function _onSwapGivenIn(
                    SwapRequest memory swapRequest,
                    uint256 currentBalanceTokenIn,
                    uint256 currentBalanceTokenOut
                ) internal view override returns (uint256) {
                    _require(getSwapEnabled(), Errors.SWAPS_DISABLED);
                    return super._onSwapGivenIn(swapRequest, currentBalanceTokenIn, currentBalanceTokenOut);
                }
                function _onSwapGivenOut(
                    SwapRequest memory swapRequest,
                    uint256 currentBalanceTokenIn,
                    uint256 currentBalanceTokenOut
                ) internal view override returns (uint256) {
                    _require(getSwapEnabled(), Errors.SWAPS_DISABLED);
                    return super._onSwapGivenOut(swapRequest, currentBalanceTokenIn, currentBalanceTokenOut);
                }
                /**
                 * @dev Extend ownerOnly functions to include the LBP control functions
                 */
                function _isOwnerOnlyAction(bytes32 actionId) internal view override returns (bool) {
                    return
                        (actionId == getActionId(LiquidityBootstrappingPool.setSwapEnabled.selector)) ||
                        (actionId == getActionId(LiquidityBootstrappingPool.updateWeightsGradually.selector)) ||
                        super._isOwnerOnlyAction(actionId);
                }
                // Private functions
                /**
                 * @dev Returns a fixed-point number representing how far along the current weight change is, where 0 means the
                 * change has not yet started, and FixedPoint.ONE means it has fully completed.
                 */
                function _calculateWeightChangeProgress(bytes32 poolState) private view returns (uint256) {
                    uint256 currentTime = block.timestamp;
                    uint256 startTime = poolState.decodeUint32(_START_TIME_OFFSET);
                    uint256 endTime = poolState.decodeUint32(_END_TIME_OFFSET);
                    if (currentTime > endTime) {
                        return FixedPoint.ONE;
                    } else if (currentTime < startTime) {
                        return 0;
                    }
                    // No need for SafeMath as it was checked right above: endTime >= currentTime >= startTime
                    uint256 totalSeconds = endTime - startTime;
                    uint256 secondsElapsed = currentTime - startTime;
                    // In the degenerate case of a zero duration change, consider it completed (and avoid division by zero)
                    return totalSeconds == 0 ? FixedPoint.ONE : secondsElapsed.divDown(totalSeconds);
                }
                /**
                 * @dev When calling updateWeightsGradually again during an update, reset the start weights to the current weights,
                 * if necessary.
                 */
                function _startGradualWeightChange(
                    uint256 startTime,
                    uint256 endTime,
                    uint256[] memory startWeights,
                    uint256[] memory endWeights
                ) internal virtual {
                    bytes32 newPoolState = _poolState;
                    uint256 normalizedSum = 0;
                    for (uint256 i = 0; i < endWeights.length; i++) {
                        uint256 endWeight = endWeights[i];
                        _require(endWeight >= _MIN_WEIGHT, Errors.MIN_WEIGHT);
                        newPoolState = newPoolState
                            .insertUint31(startWeights[i].compress31(), _START_WEIGHT_OFFSET + i * 31)
                            .insertUint16(endWeight.compress16(), _END_WEIGHT_OFFSET + i * 16);
                        normalizedSum = normalizedSum.add(endWeight);
                    }
                    // Ensure that the normalized weights sum to ONE
                    _require(normalizedSum == FixedPoint.ONE, Errors.NORMALIZED_WEIGHT_INVARIANT);
                    _poolState = newPoolState.insertUint32(startTime, _START_TIME_OFFSET).insertUint32(endTime, _END_TIME_OFFSET);
                    emit GradualWeightUpdateScheduled(startTime, endTime, startWeights, endWeights);
                }
                function _interpolateWeight(
                    uint256 startWeight,
                    uint256 endWeight,
                    uint256 pctProgress
                ) private pure returns (uint256) {
                    if (pctProgress == 0 || startWeight == endWeight) return startWeight;
                    if (pctProgress >= FixedPoint.ONE) return endWeight;
                    if (startWeight > endWeight) {
                        uint256 weightDelta = pctProgress.mulDown(startWeight - endWeight);
                        return startWeight.sub(weightDelta);
                    } else {
                        uint256 weightDelta = pctProgress.mulDown(endWeight - startWeight);
                        return startWeight.add(weightDelta);
                    }
                }
                function _setSwapEnabled(bool swapEnabled) private {
                    _poolState = _poolState.insertBool(swapEnabled, _SWAP_ENABLED_OFFSET);
                    emit SwapEnabledSet(swapEnabled);
                }
                function _getMaxTokens() internal pure override returns (uint256) {
                    return _MAX_LBP_TOKENS;
                }
                function _getTotalTokens() internal view virtual override returns (uint256) {
                    return _totalTokens;
                }
                function _scalingFactor(IERC20 token) internal view virtual override returns (uint256) {
                    // prettier-ignore
                    if (token == _token0) { return _scalingFactor0; }
                    else if (token == _token1) { return _scalingFactor1; }
                    else if (token == _token2) { return _scalingFactor2; }
                    else if (token == _token3) { return _scalingFactor3; }
                    else {
                        _revert(Errors.INVALID_TOKEN);
                    }
                }
                function _scalingFactors() internal view virtual override returns (uint256[] memory) {
                    uint256 totalTokens = _getTotalTokens();
                    uint256[] memory scalingFactors = new uint256[](totalTokens);
                    // prettier-ignore
                    {
                        if (totalTokens > 0) { scalingFactors[0] = _scalingFactor0; } else { return scalingFactors; }
                        if (totalTokens > 1) { scalingFactors[1] = _scalingFactor1; } else { return scalingFactors; }
                        if (totalTokens > 2) { scalingFactors[2] = _scalingFactor2; } else { return scalingFactors; }
                        if (totalTokens > 3) { scalingFactors[3] = _scalingFactor3; } else { return scalingFactors; }
                    }
                    return scalingFactors;
                }
            }
            // SPDX-License-Identifier: MIT
            // Based on the ReentrancyGuard library from OpenZeppelin Contracts, altered to reduce bytecode size.
            // Modifier code is inlined by the compiler, which causes its code to appear multiple times in the codebase. By using
            // private functions, we achieve the same end result with slightly higher runtime gas costs, but reduced bytecode size.
            pragma solidity ^0.7.0;
            import "../helpers/BalancerErrors.sol";
            /**
             * @dev Contract module that helps prevent reentrant calls to a function.
             *
             * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
             * available, which can be applied to functions to make sure there are no nested
             * (reentrant) calls to them.
             *
             * Note that because there is a single `nonReentrant` guard, functions marked as
             * `nonReentrant` may not call one another. This can be worked around by making
             * those functions `private`, and then adding `external` `nonReentrant` entry
             * points to them.
             *
             * TIP: If you would like to learn more about reentrancy and alternative ways
             * to protect against it, check out our blog post
             * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
             */
            abstract contract ReentrancyGuard {
                // Booleans are more expensive than uint256 or any type that takes up a full
                // word because each write operation emits an extra SLOAD to first read the
                // slot's contents, replace the bits taken up by the boolean, and then write
                // back. This is the compiler's defense against contract upgrades and
                // pointer aliasing, and it cannot be disabled.
                // The values being non-zero value makes deployment a bit more expensive,
                // but in exchange the refund on every call to nonReentrant will be lower in
                // amount. Since refunds are capped to a percentage of the total
                // transaction's gas, it is best to keep them low in cases like this one, to
                // increase the likelihood of the full refund coming into effect.
                uint256 private constant _NOT_ENTERED = 1;
                uint256 private constant _ENTERED = 2;
                uint256 private _status;
                constructor() {
                    _status = _NOT_ENTERED;
                }
                /**
                 * @dev Prevents a contract from calling itself, directly or indirectly.
                 * Calling a `nonReentrant` function from another `nonReentrant`
                 * function is not supported. It is possible to prevent this from happening
                 * by making the `nonReentrant` function external, and make it call a
                 * `private` function that does the actual work.
                 */
                modifier nonReentrant() {
                    _enterNonReentrant();
                    _;
                    _exitNonReentrant();
                }
                function _enterNonReentrant() private {
                    // On the first call to nonReentrant, _status will be _NOT_ENTERED
                    _require(_status != _ENTERED, Errors.REENTRANCY);
                    // Any calls to nonReentrant after this point will fail
                    _status = _ENTERED;
                }
                function _exitNonReentrant() private {
                    // By storing the original value once again, a refund is triggered (see
                    // https://eips.ethereum.org/EIPS/eip-2200)
                    _status = _NOT_ENTERED;
                }
            }
            // SPDX-License-Identifier: GPL-3.0-or-later
            // This program is free software: you can redistribute it and/or modify
            // it under the terms of the GNU General Public License as published by
            // the Free Software Foundation, either version 3 of the License, or
            // (at your option) any later version.
            // This program is distributed in the hope that it will be useful,
            // but WITHOUT ANY WARRANTY; without even the implied warranty of
            // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
            // GNU General Public License for more details.
            // You should have received a copy of the GNU General Public License
            // along with this program.  If not, see <http://www.gnu.org/licenses/>.
            pragma solidity ^0.7.0;
            import "@balancer-labs/v2-solidity-utils/contracts/math/FixedPoint.sol";
            /**
             * @dev Library for compressing and uncompresing numbers by using smaller types.
             * All values are 18 decimal fixed-point numbers in the [0.0, 1.0] range,
             * so heavier compression (fewer bits) results in fewer decimals.
             */
            library WeightCompression {
                uint256 private constant _UINT31_MAX = 2**(31) - 1;
                using FixedPoint for uint256;
                /**
                 * @dev Convert a 16-bit value to full FixedPoint
                 */
                function uncompress16(uint256 value) internal pure returns (uint256) {
                    return value.mulUp(FixedPoint.ONE).divUp(type(uint16).max);
                }
                /**
                 * @dev Compress a FixedPoint value to 16 bits
                 */
                function compress16(uint256 value) internal pure returns (uint256) {
                    return value.mulUp(type(uint16).max).divUp(FixedPoint.ONE);
                }
                /**
                 * @dev Convert a 31-bit value to full FixedPoint
                 */
                function uncompress31(uint256 value) internal pure returns (uint256) {
                    return value.mulUp(FixedPoint.ONE).divUp(_UINT31_MAX);
                }
                /**
                 * @dev Compress a FixedPoint value to 31 bits
                 */
                function compress31(uint256 value) internal pure returns (uint256) {
                    return value.mulUp(_UINT31_MAX).divUp(FixedPoint.ONE);
                }
            }