ETH Price: $2,511.09 (-0.56%)

Transaction Decoder

Block:
14097765 at Jan-29-2022 01:42:02 AM +UTC
Transaction Fee:
0.0267980416 ETH $67.29
Gas Used:
190,327 Gas / 140.8 Gwei

Emitted Events:

5 SphynxToken.Transfer( from=[Sender] 0xef3608b7485937fbbbf3a281f08a940257ce6a21, to=0xbe6E1164DBc3917711411A6a24BA6Fd793ab0E78, value=2143389676124335324294 )
6 SphynxToken.Transfer( from=[Sender] 0xef3608b7485937fbbbf3a281f08a940257ce6a21, to=SphynxToken, value=21433896761243353242949 )
7 SphynxToken.Transfer( from=[Sender] 0xef3608b7485937fbbbf3a281f08a940257ce6a21, to=UniswapV2Pair, value=190761681175065843862252 )
8 SphynxToken.Approval( owner=[Sender] 0xef3608b7485937fbbbf3a281f08a940257ce6a21, spender=[Receiver] SwapRouter02, value=0 )
9 WETH9.Transfer( src=UniswapV2Pair, dst=[Receiver] SwapRouter02, wad=72368452535503211 )
10 UniswapV2Pair.Sync( reserve0=217394488627139058711227705, reserve1=82647602462294354512 )
11 UniswapV2Pair.Swap( sender=[Receiver] SwapRouter02, amount0In=190761681175065843862252, amount1In=0, amount0Out=0, amount1Out=72368452535503211, to=[Receiver] SwapRouter02 )
12 WETH9.Withdrawal( src=[Receiver] SwapRouter02, wad=72368452535503211 )

Account State Difference:

  Address   Before After State Difference Code
(F2Pool Old)
6,280.764515496446730553 Eth6,280.76827982147485897 Eth0.003764325028128417
0x94DFd4E2...9dA6640f8
0xC02aaA39...83C756Cc2 8,068,548.985604396098012178 Eth8,068,548.913235943562508967 Eth0.072368452535503211
0xC98cE365...54aB3739B
0xEf3608B7...257CE6A21
0.147029059290130883 Eth
Nonce: 39
0.192599470225634094 Eth
Nonce: 40
0.045570410935503211

Execution Trace

SwapRouter02.multicall( deadline=1643422297, data=[RytD8wAAAAAAAAAAAAAAAAAAAAAAAAAAAAAtY1a2IvzQu6S3AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAPSwXIEH+zkAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAgAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAACAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAIAAAAAAAAAAAAAAACU39TiIQ+lt1LDzQ84HtrZ2mZA+AAAAAAAAAAAAAAAAMAqqjmyI/6NCg5cTyfq2Qg8dWzC, SUBLfAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAD0sFyBB/s5AAAAAAAAAAAAAAAA7zYIt0hZN/u786KB8IqUAlfOaiE=] ) => ( [AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAQEauWJSyWs=, ] )
  • SwapRouter02.swapExactTokensForTokens( amountIn=214338967612433532429495, amountOutMin=68873805665663801, path=[0x94DFd4E2210Fa5B752c3CD0f381edad9dA6640f8, 0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2], to=0x0000000000000000000000000000000000000002 ) => ( amountOut=72368452535503211 )
    • SphynxToken.transferFrom( sender=0xEf3608B7485937FBbBF3a281F08a940257CE6A21, recipient=0xC98cE365c06c4f75aF2399811fB1d8A54aB3739B, amount=214338967612433532429495 ) => ( True )
      • UniswapV2Router02.STATICCALL( )
      • EACAggregatorProxy.STATICCALL( )
        • AccessControlledOffchainAggregator.STATICCALL( )
        • UniswapV2Router02.getAmountsOut( amountIn=196308037120418309, path=[0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2, 0x94DFd4E2210Fa5B752c3CD0f381edad9dA6640f8] ) => ( amounts=[196308037120418309, 512700560845027886690969] )
          • UniswapV2Pair.STATICCALL( )
          • WETH9.balanceOf( 0x68b3465833fb72A70ecDF485E0e4C7bD8665Fc45 ) => ( 0 )
          • UniswapV2Pair.STATICCALL( )
          • SphynxToken.balanceOf( account=0xC98cE365c06c4f75aF2399811fB1d8A54aB3739B ) => ( 217394488627139058711227705 )
          • UniswapV2Pair.swap( amount0Out=0, amount1Out=72368452535503211, to=0x68b3465833fb72A70ecDF485E0e4C7bD8665Fc45, data=0x )
            • WETH9.transfer( dst=0x68b3465833fb72A70ecDF485E0e4C7bD8665Fc45, wad=72368452535503211 ) => ( True )
            • SphynxToken.balanceOf( account=0xC98cE365c06c4f75aF2399811fB1d8A54aB3739B ) => ( 217394488627139058711227705 )
            • WETH9.balanceOf( 0xC98cE365c06c4f75aF2399811fB1d8A54aB3739B ) => ( 82647602462294354512 )
            • WETH9.balanceOf( 0x68b3465833fb72A70ecDF485E0e4C7bD8665Fc45 ) => ( 72368452535503211 )
            • SwapRouter02.unwrapWETH9( amountMinimum=68873805665663801, recipient=0xEf3608B7485937FBbBF3a281F08a940257CE6A21 )
              • WETH9.balanceOf( 0x68b3465833fb72A70ecDF485E0e4C7bD8665Fc45 ) => ( 72368452535503211 )
              • WETH9.withdraw( wad=72368452535503211 )
                • ETH 0.072368452535503211 SwapRouter02.CALL( )
                • ETH 0.072368452535503211 0xef3608b7485937fbbbf3a281f08a940257ce6a21.CALL( )
                  File 1 of 7: SwapRouter02
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity =0.7.6;
                  pragma abicoder v2;
                  import '@uniswap/v3-periphery/contracts/base/SelfPermit.sol';
                  import '@uniswap/v3-periphery/contracts/base/PeripheryImmutableState.sol';
                  import './interfaces/ISwapRouter02.sol';
                  import './V2SwapRouter.sol';
                  import './V3SwapRouter.sol';
                  import './base/ApproveAndCall.sol';
                  import './base/MulticallExtended.sol';
                  /// @title Uniswap V2 and V3 Swap Router
                  contract SwapRouter02 is ISwapRouter02, V2SwapRouter, V3SwapRouter, ApproveAndCall, MulticallExtended, SelfPermit {
                      constructor(
                          address _factoryV2,
                          address factoryV3,
                          address _positionManager,
                          address _WETH9
                      ) ImmutableState(_factoryV2, _positionManager) PeripheryImmutableState(factoryV3, _WETH9) {}
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.5.0;
                  import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
                  import '@openzeppelin/contracts/drafts/IERC20Permit.sol';
                  import '../interfaces/ISelfPermit.sol';
                  import '../interfaces/external/IERC20PermitAllowed.sol';
                  /// @title Self Permit
                  /// @notice Functionality to call permit on any EIP-2612-compliant token for use in the route
                  /// @dev These functions are expected to be embedded in multicalls to allow EOAs to approve a contract and call a function
                  /// that requires an approval in a single transaction.
                  abstract contract SelfPermit is ISelfPermit {
                      /// @inheritdoc ISelfPermit
                      function selfPermit(
                          address token,
                          uint256 value,
                          uint256 deadline,
                          uint8 v,
                          bytes32 r,
                          bytes32 s
                      ) public payable override {
                          IERC20Permit(token).permit(msg.sender, address(this), value, deadline, v, r, s);
                      }
                      /// @inheritdoc ISelfPermit
                      function selfPermitIfNecessary(
                          address token,
                          uint256 value,
                          uint256 deadline,
                          uint8 v,
                          bytes32 r,
                          bytes32 s
                      ) external payable override {
                          if (IERC20(token).allowance(msg.sender, address(this)) < value) selfPermit(token, value, deadline, v, r, s);
                      }
                      /// @inheritdoc ISelfPermit
                      function selfPermitAllowed(
                          address token,
                          uint256 nonce,
                          uint256 expiry,
                          uint8 v,
                          bytes32 r,
                          bytes32 s
                      ) public payable override {
                          IERC20PermitAllowed(token).permit(msg.sender, address(this), nonce, expiry, true, v, r, s);
                      }
                      /// @inheritdoc ISelfPermit
                      function selfPermitAllowedIfNecessary(
                          address token,
                          uint256 nonce,
                          uint256 expiry,
                          uint8 v,
                          bytes32 r,
                          bytes32 s
                      ) external payable override {
                          if (IERC20(token).allowance(msg.sender, address(this)) < type(uint256).max)
                              selfPermitAllowed(token, nonce, expiry, v, r, s);
                      }
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity =0.7.6;
                  import '../interfaces/IPeripheryImmutableState.sol';
                  /// @title Immutable state
                  /// @notice Immutable state used by periphery contracts
                  abstract contract PeripheryImmutableState is IPeripheryImmutableState {
                      /// @inheritdoc IPeripheryImmutableState
                      address public immutable override factory;
                      /// @inheritdoc IPeripheryImmutableState
                      address public immutable override WETH9;
                      constructor(address _factory, address _WETH9) {
                          factory = _factory;
                          WETH9 = _WETH9;
                      }
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.7.5;
                  pragma abicoder v2;
                  import '@uniswap/v3-periphery/contracts/interfaces/ISelfPermit.sol';
                  import './IV2SwapRouter.sol';
                  import './IV3SwapRouter.sol';
                  import './IApproveAndCall.sol';
                  import './IMulticallExtended.sol';
                  /// @title Router token swapping functionality
                  interface ISwapRouter02 is IV2SwapRouter, IV3SwapRouter, IApproveAndCall, IMulticallExtended, ISelfPermit {
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity =0.7.6;
                  pragma abicoder v2;
                  import '@uniswap/v3-core/contracts/libraries/LowGasSafeMath.sol';
                  import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
                  import './interfaces/IV2SwapRouter.sol';
                  import './base/ImmutableState.sol';
                  import './base/PeripheryPaymentsWithFeeExtended.sol';
                  import './libraries/Constants.sol';
                  import './libraries/UniswapV2Library.sol';
                  /// @title Uniswap V2 Swap Router
                  /// @notice Router for stateless execution of swaps against Uniswap V2
                  abstract contract V2SwapRouter is IV2SwapRouter, ImmutableState, PeripheryPaymentsWithFeeExtended {
                      using LowGasSafeMath for uint256;
                      // supports fee-on-transfer tokens
                      // requires the initial amount to have already been sent to the first pair
                      function _swap(address[] memory path, address _to) private {
                          for (uint256 i; i < path.length - 1; i++) {
                              (address input, address output) = (path[i], path[i + 1]);
                              (address token0, ) = UniswapV2Library.sortTokens(input, output);
                              IUniswapV2Pair pair = IUniswapV2Pair(UniswapV2Library.pairFor(factoryV2, input, output));
                              uint256 amountInput;
                              uint256 amountOutput;
                              // scope to avoid stack too deep errors
                              {
                                  (uint256 reserve0, uint256 reserve1, ) = pair.getReserves();
                                  (uint256 reserveInput, uint256 reserveOutput) =
                                      input == token0 ? (reserve0, reserve1) : (reserve1, reserve0);
                                  amountInput = IERC20(input).balanceOf(address(pair)).sub(reserveInput);
                                  amountOutput = UniswapV2Library.getAmountOut(amountInput, reserveInput, reserveOutput);
                              }
                              (uint256 amount0Out, uint256 amount1Out) =
                                  input == token0 ? (uint256(0), amountOutput) : (amountOutput, uint256(0));
                              address to = i < path.length - 2 ? UniswapV2Library.pairFor(factoryV2, output, path[i + 2]) : _to;
                              pair.swap(amount0Out, amount1Out, to, new bytes(0));
                          }
                      }
                      /// @inheritdoc IV2SwapRouter
                      function swapExactTokensForTokens(
                          uint256 amountIn,
                          uint256 amountOutMin,
                          address[] calldata path,
                          address to
                      ) external payable override returns (uint256 amountOut) {
                          // use amountIn == Constants.CONTRACT_BALANCE as a flag to swap the entire balance of the contract
                          bool hasAlreadyPaid;
                          if (amountIn == Constants.CONTRACT_BALANCE) {
                              hasAlreadyPaid = true;
                              amountIn = IERC20(path[0]).balanceOf(address(this));
                          }
                          pay(
                              path[0],
                              hasAlreadyPaid ? address(this) : msg.sender,
                              UniswapV2Library.pairFor(factoryV2, path[0], path[1]),
                              amountIn
                          );
                          // find and replace to addresses
                          if (to == Constants.MSG_SENDER) to = msg.sender;
                          else if (to == Constants.ADDRESS_THIS) to = address(this);
                          uint256 balanceBefore = IERC20(path[path.length - 1]).balanceOf(to);
                          _swap(path, to);
                          amountOut = IERC20(path[path.length - 1]).balanceOf(to).sub(balanceBefore);
                          require(amountOut >= amountOutMin, 'Too little received');
                      }
                      /// @inheritdoc IV2SwapRouter
                      function swapTokensForExactTokens(
                          uint256 amountOut,
                          uint256 amountInMax,
                          address[] calldata path,
                          address to
                      ) external payable override returns (uint256 amountIn) {
                          amountIn = UniswapV2Library.getAmountsIn(factoryV2, amountOut, path)[0];
                          require(amountIn <= amountInMax, 'Too much requested');
                          pay(path[0], msg.sender, UniswapV2Library.pairFor(factoryV2, path[0], path[1]), amountIn);
                          // find and replace to addresses
                          if (to == Constants.MSG_SENDER) to = msg.sender;
                          else if (to == Constants.ADDRESS_THIS) to = address(this);
                          _swap(path, to);
                      }
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity =0.7.6;
                  pragma abicoder v2;
                  import '@uniswap/v3-core/contracts/libraries/SafeCast.sol';
                  import '@uniswap/v3-core/contracts/libraries/TickMath.sol';
                  import '@uniswap/v3-core/contracts/interfaces/IUniswapV3Pool.sol';
                  import '@uniswap/v3-periphery/contracts/libraries/Path.sol';
                  import '@uniswap/v3-periphery/contracts/libraries/PoolAddress.sol';
                  import '@uniswap/v3-periphery/contracts/libraries/CallbackValidation.sol';
                  import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
                  import './interfaces/IV3SwapRouter.sol';
                  import './base/PeripheryPaymentsWithFeeExtended.sol';
                  import './base/OracleSlippage.sol';
                  import './libraries/Constants.sol';
                  /// @title Uniswap V3 Swap Router
                  /// @notice Router for stateless execution of swaps against Uniswap V3
                  abstract contract V3SwapRouter is IV3SwapRouter, PeripheryPaymentsWithFeeExtended, OracleSlippage {
                      using Path for bytes;
                      using SafeCast for uint256;
                      /// @dev Used as the placeholder value for amountInCached, because the computed amount in for an exact output swap
                      /// can never actually be this value
                      uint256 private constant DEFAULT_AMOUNT_IN_CACHED = type(uint256).max;
                      /// @dev Transient storage variable used for returning the computed amount in for an exact output swap.
                      uint256 private amountInCached = DEFAULT_AMOUNT_IN_CACHED;
                      /// @dev Returns the pool for the given token pair and fee. The pool contract may or may not exist.
                      function getPool(
                          address tokenA,
                          address tokenB,
                          uint24 fee
                      ) private view returns (IUniswapV3Pool) {
                          return IUniswapV3Pool(PoolAddress.computeAddress(factory, PoolAddress.getPoolKey(tokenA, tokenB, fee)));
                      }
                      struct SwapCallbackData {
                          bytes path;
                          address payer;
                      }
                      /// @inheritdoc IUniswapV3SwapCallback
                      function uniswapV3SwapCallback(
                          int256 amount0Delta,
                          int256 amount1Delta,
                          bytes calldata _data
                      ) external override {
                          require(amount0Delta > 0 || amount1Delta > 0); // swaps entirely within 0-liquidity regions are not supported
                          SwapCallbackData memory data = abi.decode(_data, (SwapCallbackData));
                          (address tokenIn, address tokenOut, uint24 fee) = data.path.decodeFirstPool();
                          CallbackValidation.verifyCallback(factory, tokenIn, tokenOut, fee);
                          (bool isExactInput, uint256 amountToPay) =
                              amount0Delta > 0
                                  ? (tokenIn < tokenOut, uint256(amount0Delta))
                                  : (tokenOut < tokenIn, uint256(amount1Delta));
                          if (isExactInput) {
                              pay(tokenIn, data.payer, msg.sender, amountToPay);
                          } else {
                              // either initiate the next swap or pay
                              if (data.path.hasMultiplePools()) {
                                  data.path = data.path.skipToken();
                                  exactOutputInternal(amountToPay, msg.sender, 0, data);
                              } else {
                                  amountInCached = amountToPay;
                                  // note that because exact output swaps are executed in reverse order, tokenOut is actually tokenIn
                                  pay(tokenOut, data.payer, msg.sender, amountToPay);
                              }
                          }
                      }
                      /// @dev Performs a single exact input swap
                      function exactInputInternal(
                          uint256 amountIn,
                          address recipient,
                          uint160 sqrtPriceLimitX96,
                          SwapCallbackData memory data
                      ) private returns (uint256 amountOut) {
                          // find and replace recipient addresses
                          if (recipient == Constants.MSG_SENDER) recipient = msg.sender;
                          else if (recipient == Constants.ADDRESS_THIS) recipient = address(this);
                          (address tokenIn, address tokenOut, uint24 fee) = data.path.decodeFirstPool();
                          bool zeroForOne = tokenIn < tokenOut;
                          (int256 amount0, int256 amount1) =
                              getPool(tokenIn, tokenOut, fee).swap(
                                  recipient,
                                  zeroForOne,
                                  amountIn.toInt256(),
                                  sqrtPriceLimitX96 == 0
                                      ? (zeroForOne ? TickMath.MIN_SQRT_RATIO + 1 : TickMath.MAX_SQRT_RATIO - 1)
                                      : sqrtPriceLimitX96,
                                  abi.encode(data)
                              );
                          return uint256(-(zeroForOne ? amount1 : amount0));
                      }
                      /// @inheritdoc IV3SwapRouter
                      function exactInputSingle(ExactInputSingleParams memory params)
                          external
                          payable
                          override
                          returns (uint256 amountOut)
                      {
                          // use amountIn == Constants.CONTRACT_BALANCE as a flag to swap the entire balance of the contract
                          bool hasAlreadyPaid;
                          if (params.amountIn == Constants.CONTRACT_BALANCE) {
                              hasAlreadyPaid = true;
                              params.amountIn = IERC20(params.tokenIn).balanceOf(address(this));
                          }
                          amountOut = exactInputInternal(
                              params.amountIn,
                              params.recipient,
                              params.sqrtPriceLimitX96,
                              SwapCallbackData({
                                  path: abi.encodePacked(params.tokenIn, params.fee, params.tokenOut),
                                  payer: hasAlreadyPaid ? address(this) : msg.sender
                              })
                          );
                          require(amountOut >= params.amountOutMinimum, 'Too little received');
                      }
                      /// @inheritdoc IV3SwapRouter
                      function exactInput(ExactInputParams memory params) external payable override returns (uint256 amountOut) {
                          // use amountIn == Constants.CONTRACT_BALANCE as a flag to swap the entire balance of the contract
                          bool hasAlreadyPaid;
                          if (params.amountIn == Constants.CONTRACT_BALANCE) {
                              hasAlreadyPaid = true;
                              (address tokenIn, , ) = params.path.decodeFirstPool();
                              params.amountIn = IERC20(tokenIn).balanceOf(address(this));
                          }
                          address payer = hasAlreadyPaid ? address(this) : msg.sender;
                          while (true) {
                              bool hasMultiplePools = params.path.hasMultiplePools();
                              // the outputs of prior swaps become the inputs to subsequent ones
                              params.amountIn = exactInputInternal(
                                  params.amountIn,
                                  hasMultiplePools ? address(this) : params.recipient, // for intermediate swaps, this contract custodies
                                  0,
                                  SwapCallbackData({
                                      path: params.path.getFirstPool(), // only the first pool in the path is necessary
                                      payer: payer
                                  })
                              );
                              // decide whether to continue or terminate
                              if (hasMultiplePools) {
                                  payer = address(this);
                                  params.path = params.path.skipToken();
                              } else {
                                  amountOut = params.amountIn;
                                  break;
                              }
                          }
                          require(amountOut >= params.amountOutMinimum, 'Too little received');
                      }
                      /// @dev Performs a single exact output swap
                      function exactOutputInternal(
                          uint256 amountOut,
                          address recipient,
                          uint160 sqrtPriceLimitX96,
                          SwapCallbackData memory data
                      ) private returns (uint256 amountIn) {
                          // find and replace recipient addresses
                          if (recipient == Constants.MSG_SENDER) recipient = msg.sender;
                          else if (recipient == Constants.ADDRESS_THIS) recipient = address(this);
                          (address tokenOut, address tokenIn, uint24 fee) = data.path.decodeFirstPool();
                          bool zeroForOne = tokenIn < tokenOut;
                          (int256 amount0Delta, int256 amount1Delta) =
                              getPool(tokenIn, tokenOut, fee).swap(
                                  recipient,
                                  zeroForOne,
                                  -amountOut.toInt256(),
                                  sqrtPriceLimitX96 == 0
                                      ? (zeroForOne ? TickMath.MIN_SQRT_RATIO + 1 : TickMath.MAX_SQRT_RATIO - 1)
                                      : sqrtPriceLimitX96,
                                  abi.encode(data)
                              );
                          uint256 amountOutReceived;
                          (amountIn, amountOutReceived) = zeroForOne
                              ? (uint256(amount0Delta), uint256(-amount1Delta))
                              : (uint256(amount1Delta), uint256(-amount0Delta));
                          // it's technically possible to not receive the full output amount,
                          // so if no price limit has been specified, require this possibility away
                          if (sqrtPriceLimitX96 == 0) require(amountOutReceived == amountOut);
                      }
                      /// @inheritdoc IV3SwapRouter
                      function exactOutputSingle(ExactOutputSingleParams calldata params)
                          external
                          payable
                          override
                          returns (uint256 amountIn)
                      {
                          // avoid an SLOAD by using the swap return data
                          amountIn = exactOutputInternal(
                              params.amountOut,
                              params.recipient,
                              params.sqrtPriceLimitX96,
                              SwapCallbackData({path: abi.encodePacked(params.tokenOut, params.fee, params.tokenIn), payer: msg.sender})
                          );
                          require(amountIn <= params.amountInMaximum, 'Too much requested');
                          // has to be reset even though we don't use it in the single hop case
                          amountInCached = DEFAULT_AMOUNT_IN_CACHED;
                      }
                      /// @inheritdoc IV3SwapRouter
                      function exactOutput(ExactOutputParams calldata params) external payable override returns (uint256 amountIn) {
                          exactOutputInternal(
                              params.amountOut,
                              params.recipient,
                              0,
                              SwapCallbackData({path: params.path, payer: msg.sender})
                          );
                          amountIn = amountInCached;
                          require(amountIn <= params.amountInMaximum, 'Too much requested');
                          amountInCached = DEFAULT_AMOUNT_IN_CACHED;
                      }
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity =0.7.6;
                  pragma abicoder v2;
                  import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
                  import '@uniswap/v3-periphery/contracts/interfaces/INonfungiblePositionManager.sol';
                  import '../interfaces/IApproveAndCall.sol';
                  import './ImmutableState.sol';
                  /// @title Approve and Call
                  /// @notice Allows callers to approve the Uniswap V3 position manager from this contract,
                  /// for any token, and then make calls into the position manager
                  abstract contract ApproveAndCall is IApproveAndCall, ImmutableState {
                      function tryApprove(address token, uint256 amount) private returns (bool) {
                          (bool success, bytes memory data) =
                              token.call(abi.encodeWithSelector(IERC20.approve.selector, positionManager, amount));
                          return success && (data.length == 0 || abi.decode(data, (bool)));
                      }
                      /// @inheritdoc IApproveAndCall
                      function getApprovalType(address token, uint256 amount) external override returns (ApprovalType) {
                          // check existing approval
                          if (IERC20(token).allowance(address(this), positionManager) >= amount) return ApprovalType.NOT_REQUIRED;
                          // try type(uint256).max / type(uint256).max - 1
                          if (tryApprove(token, type(uint256).max)) return ApprovalType.MAX;
                          if (tryApprove(token, type(uint256).max - 1)) return ApprovalType.MAX_MINUS_ONE;
                          // set approval to 0 (must succeed)
                          require(tryApprove(token, 0));
                          // try type(uint256).max / type(uint256).max - 1
                          if (tryApprove(token, type(uint256).max)) return ApprovalType.ZERO_THEN_MAX;
                          if (tryApprove(token, type(uint256).max - 1)) return ApprovalType.ZERO_THEN_MAX_MINUS_ONE;
                          revert();
                      }
                      /// @inheritdoc IApproveAndCall
                      function approveMax(address token) external payable override {
                          require(tryApprove(token, type(uint256).max));
                      }
                      /// @inheritdoc IApproveAndCall
                      function approveMaxMinusOne(address token) external payable override {
                          require(tryApprove(token, type(uint256).max - 1));
                      }
                      /// @inheritdoc IApproveAndCall
                      function approveZeroThenMax(address token) external payable override {
                          require(tryApprove(token, 0));
                          require(tryApprove(token, type(uint256).max));
                      }
                      /// @inheritdoc IApproveAndCall
                      function approveZeroThenMaxMinusOne(address token) external payable override {
                          require(tryApprove(token, 0));
                          require(tryApprove(token, type(uint256).max - 1));
                      }
                      /// @inheritdoc IApproveAndCall
                      function callPositionManager(bytes memory data) public payable override returns (bytes memory result) {
                          bool success;
                          (success, result) = positionManager.call(data);
                          if (!success) {
                              // Next 5 lines from https://ethereum.stackexchange.com/a/83577
                              if (result.length < 68) revert();
                              assembly {
                                  result := add(result, 0x04)
                              }
                              revert(abi.decode(result, (string)));
                          }
                      }
                      function balanceOf(address token) private view returns (uint256) {
                          return IERC20(token).balanceOf(address(this));
                      }
                      /// @inheritdoc IApproveAndCall
                      function mint(MintParams calldata params) external payable override returns (bytes memory result) {
                          return
                              callPositionManager(
                                  abi.encodeWithSelector(
                                      INonfungiblePositionManager.mint.selector,
                                      INonfungiblePositionManager.MintParams({
                                          token0: params.token0,
                                          token1: params.token1,
                                          fee: params.fee,
                                          tickLower: params.tickLower,
                                          tickUpper: params.tickUpper,
                                          amount0Desired: balanceOf(params.token0),
                                          amount1Desired: balanceOf(params.token1),
                                          amount0Min: params.amount0Min,
                                          amount1Min: params.amount1Min,
                                          recipient: params.recipient,
                                          deadline: type(uint256).max // deadline should be checked via multicall
                                      })
                                  )
                              );
                      }
                      /// @inheritdoc IApproveAndCall
                      function increaseLiquidity(IncreaseLiquidityParams calldata params)
                          external
                          payable
                          override
                          returns (bytes memory result)
                      {
                          return
                              callPositionManager(
                                  abi.encodeWithSelector(
                                      INonfungiblePositionManager.increaseLiquidity.selector,
                                      INonfungiblePositionManager.IncreaseLiquidityParams({
                                          tokenId: params.tokenId,
                                          amount0Desired: balanceOf(params.token0),
                                          amount1Desired: balanceOf(params.token1),
                                          amount0Min: params.amount0Min,
                                          amount1Min: params.amount1Min,
                                          deadline: type(uint256).max // deadline should be checked via multicall
                                      })
                                  )
                              );
                      }
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity =0.7.6;
                  pragma abicoder v2;
                  import '@uniswap/v3-periphery/contracts/base/Multicall.sol';
                  import '../interfaces/IMulticallExtended.sol';
                  import '../base/PeripheryValidationExtended.sol';
                  /// @title Multicall
                  /// @notice Enables calling multiple methods in a single call to the contract
                  abstract contract MulticallExtended is IMulticallExtended, Multicall, PeripheryValidationExtended {
                      /// @inheritdoc IMulticallExtended
                      function multicall(uint256 deadline, bytes[] calldata data)
                          external
                          payable
                          override
                          checkDeadline(deadline)
                          returns (bytes[] memory)
                      {
                          return multicall(data);
                      }
                      /// @inheritdoc IMulticallExtended
                      function multicall(bytes32 previousBlockhash, bytes[] calldata data)
                          external
                          payable
                          override
                          checkPreviousBlockhash(previousBlockhash)
                          returns (bytes[] memory)
                      {
                          return multicall(data);
                      }
                  }
                  // 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: MIT
                  pragma solidity >=0.6.0 <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);
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.7.5;
                  /// @title Self Permit
                  /// @notice Functionality to call permit on any EIP-2612-compliant token for use in the route
                  interface ISelfPermit {
                      /// @notice Permits this contract to spend a given token from `msg.sender`
                      /// @dev The `owner` is always msg.sender and the `spender` is always address(this).
                      /// @param token The address of the token spent
                      /// @param value The amount that can be spent of token
                      /// @param deadline A timestamp, the current blocktime must be less than or equal to this timestamp
                      /// @param v Must produce valid secp256k1 signature from the holder along with `r` and `s`
                      /// @param r Must produce valid secp256k1 signature from the holder along with `v` and `s`
                      /// @param s Must produce valid secp256k1 signature from the holder along with `r` and `v`
                      function selfPermit(
                          address token,
                          uint256 value,
                          uint256 deadline,
                          uint8 v,
                          bytes32 r,
                          bytes32 s
                      ) external payable;
                      /// @notice Permits this contract to spend a given token from `msg.sender`
                      /// @dev The `owner` is always msg.sender and the `spender` is always address(this).
                      /// Can be used instead of #selfPermit to prevent calls from failing due to a frontrun of a call to #selfPermit
                      /// @param token The address of the token spent
                      /// @param value The amount that can be spent of token
                      /// @param deadline A timestamp, the current blocktime must be less than or equal to this timestamp
                      /// @param v Must produce valid secp256k1 signature from the holder along with `r` and `s`
                      /// @param r Must produce valid secp256k1 signature from the holder along with `v` and `s`
                      /// @param s Must produce valid secp256k1 signature from the holder along with `r` and `v`
                      function selfPermitIfNecessary(
                          address token,
                          uint256 value,
                          uint256 deadline,
                          uint8 v,
                          bytes32 r,
                          bytes32 s
                      ) external payable;
                      /// @notice Permits this contract to spend the sender's tokens for permit signatures that have the `allowed` parameter
                      /// @dev The `owner` is always msg.sender and the `spender` is always address(this)
                      /// @param token The address of the token spent
                      /// @param nonce The current nonce of the owner
                      /// @param expiry The timestamp at which the permit is no longer valid
                      /// @param v Must produce valid secp256k1 signature from the holder along with `r` and `s`
                      /// @param r Must produce valid secp256k1 signature from the holder along with `v` and `s`
                      /// @param s Must produce valid secp256k1 signature from the holder along with `r` and `v`
                      function selfPermitAllowed(
                          address token,
                          uint256 nonce,
                          uint256 expiry,
                          uint8 v,
                          bytes32 r,
                          bytes32 s
                      ) external payable;
                      /// @notice Permits this contract to spend the sender's tokens for permit signatures that have the `allowed` parameter
                      /// @dev The `owner` is always msg.sender and the `spender` is always address(this)
                      /// Can be used instead of #selfPermitAllowed to prevent calls from failing due to a frontrun of a call to #selfPermitAllowed.
                      /// @param token The address of the token spent
                      /// @param nonce The current nonce of the owner
                      /// @param expiry The timestamp at which the permit is no longer valid
                      /// @param v Must produce valid secp256k1 signature from the holder along with `r` and `s`
                      /// @param r Must produce valid secp256k1 signature from the holder along with `v` and `s`
                      /// @param s Must produce valid secp256k1 signature from the holder along with `r` and `v`
                      function selfPermitAllowedIfNecessary(
                          address token,
                          uint256 nonce,
                          uint256 expiry,
                          uint8 v,
                          bytes32 r,
                          bytes32 s
                      ) external payable;
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.5.0;
                  /// @title Interface for permit
                  /// @notice Interface used by DAI/CHAI for permit
                  interface IERC20PermitAllowed {
                      /// @notice Approve the spender to spend some tokens via the holder signature
                      /// @dev This is the permit interface used by DAI and CHAI
                      /// @param holder The address of the token holder, the token owner
                      /// @param spender The address of the token spender
                      /// @param nonce The holder's nonce, increases at each call to permit
                      /// @param expiry The timestamp at which the permit is no longer valid
                      /// @param allowed Boolean that sets approval amount, true for type(uint256).max and false for 0
                      /// @param v Must produce valid secp256k1 signature from the holder along with `r` and `s`
                      /// @param r Must produce valid secp256k1 signature from the holder along with `v` and `s`
                      /// @param s Must produce valid secp256k1 signature from the holder along with `r` and `v`
                      function permit(
                          address holder,
                          address spender,
                          uint256 nonce,
                          uint256 expiry,
                          bool allowed,
                          uint8 v,
                          bytes32 r,
                          bytes32 s
                      ) external;
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.5.0;
                  /// @title Immutable state
                  /// @notice Functions that return immutable state of the router
                  interface IPeripheryImmutableState {
                      /// @return Returns the address of the Uniswap V3 factory
                      function factory() external view returns (address);
                      /// @return Returns the address of WETH9
                      function WETH9() external view returns (address);
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.7.5;
                  pragma abicoder v2;
                  /// @title Router token swapping functionality
                  /// @notice Functions for swapping tokens via Uniswap V2
                  interface IV2SwapRouter {
                      /// @notice Swaps `amountIn` of one token for as much as possible of another token
                      /// @dev Setting `amountIn` to 0 will cause the contract to look up its own balance,
                      /// and swap the entire amount, enabling contracts to send tokens before calling this function.
                      /// @param amountIn The amount of token to swap
                      /// @param amountOutMin The minimum amount of output that must be received
                      /// @param path The ordered list of tokens to swap through
                      /// @param to The recipient address
                      /// @return amountOut The amount of the received token
                      function swapExactTokensForTokens(
                          uint256 amountIn,
                          uint256 amountOutMin,
                          address[] calldata path,
                          address to
                      ) external payable returns (uint256 amountOut);
                      /// @notice Swaps as little as possible of one token for an exact amount of another token
                      /// @param amountOut The amount of token to swap for
                      /// @param amountInMax The maximum amount of input that the caller will pay
                      /// @param path The ordered list of tokens to swap through
                      /// @param to The recipient address
                      /// @return amountIn The amount of token to pay
                      function swapTokensForExactTokens(
                          uint256 amountOut,
                          uint256 amountInMax,
                          address[] calldata path,
                          address to
                      ) external payable returns (uint256 amountIn);
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.7.5;
                  pragma abicoder v2;
                  import '@uniswap/v3-core/contracts/interfaces/callback/IUniswapV3SwapCallback.sol';
                  /// @title Router token swapping functionality
                  /// @notice Functions for swapping tokens via Uniswap V3
                  interface IV3SwapRouter is IUniswapV3SwapCallback {
                      struct ExactInputSingleParams {
                          address tokenIn;
                          address tokenOut;
                          uint24 fee;
                          address recipient;
                          uint256 amountIn;
                          uint256 amountOutMinimum;
                          uint160 sqrtPriceLimitX96;
                      }
                      /// @notice Swaps `amountIn` of one token for as much as possible of another token
                      /// @dev Setting `amountIn` to 0 will cause the contract to look up its own balance,
                      /// and swap the entire amount, enabling contracts to send tokens before calling this function.
                      /// @param params The parameters necessary for the swap, encoded as `ExactInputSingleParams` in calldata
                      /// @return amountOut The amount of the received token
                      function exactInputSingle(ExactInputSingleParams calldata params) external payable returns (uint256 amountOut);
                      struct ExactInputParams {
                          bytes path;
                          address recipient;
                          uint256 amountIn;
                          uint256 amountOutMinimum;
                      }
                      /// @notice Swaps `amountIn` of one token for as much as possible of another along the specified path
                      /// @dev Setting `amountIn` to 0 will cause the contract to look up its own balance,
                      /// and swap the entire amount, enabling contracts to send tokens before calling this function.
                      /// @param params The parameters necessary for the multi-hop swap, encoded as `ExactInputParams` in calldata
                      /// @return amountOut The amount of the received token
                      function exactInput(ExactInputParams calldata params) external payable returns (uint256 amountOut);
                      struct ExactOutputSingleParams {
                          address tokenIn;
                          address tokenOut;
                          uint24 fee;
                          address recipient;
                          uint256 amountOut;
                          uint256 amountInMaximum;
                          uint160 sqrtPriceLimitX96;
                      }
                      /// @notice Swaps as little as possible of one token for `amountOut` of another token
                      /// that may remain in the router after the swap.
                      /// @param params The parameters necessary for the swap, encoded as `ExactOutputSingleParams` in calldata
                      /// @return amountIn The amount of the input token
                      function exactOutputSingle(ExactOutputSingleParams calldata params) external payable returns (uint256 amountIn);
                      struct ExactOutputParams {
                          bytes path;
                          address recipient;
                          uint256 amountOut;
                          uint256 amountInMaximum;
                      }
                      /// @notice Swaps as little as possible of one token for `amountOut` of another along the specified path (reversed)
                      /// that may remain in the router after the swap.
                      /// @param params The parameters necessary for the multi-hop swap, encoded as `ExactOutputParams` in calldata
                      /// @return amountIn The amount of the input token
                      function exactOutput(ExactOutputParams calldata params) external payable returns (uint256 amountIn);
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity =0.7.6;
                  pragma abicoder v2;
                  interface IApproveAndCall {
                      enum ApprovalType {NOT_REQUIRED, MAX, MAX_MINUS_ONE, ZERO_THEN_MAX, ZERO_THEN_MAX_MINUS_ONE}
                      /// @dev Lens to be called off-chain to determine which (if any) of the relevant approval functions should be called
                      /// @param token The token to approve
                      /// @param amount The amount to approve
                      /// @return The required approval type
                      function getApprovalType(address token, uint256 amount) external returns (ApprovalType);
                      /// @notice Approves a token for the maximum possible amount
                      /// @param token The token to approve
                      function approveMax(address token) external payable;
                      /// @notice Approves a token for the maximum possible amount minus one
                      /// @param token The token to approve
                      function approveMaxMinusOne(address token) external payable;
                      /// @notice Approves a token for zero, then the maximum possible amount
                      /// @param token The token to approve
                      function approveZeroThenMax(address token) external payable;
                      /// @notice Approves a token for zero, then the maximum possible amount minus one
                      /// @param token The token to approve
                      function approveZeroThenMaxMinusOne(address token) external payable;
                      /// @notice Calls the position manager with arbitrary calldata
                      /// @param data Calldata to pass along to the position manager
                      /// @return result The result from the call
                      function callPositionManager(bytes memory data) external payable returns (bytes memory result);
                      struct MintParams {
                          address token0;
                          address token1;
                          uint24 fee;
                          int24 tickLower;
                          int24 tickUpper;
                          uint256 amount0Min;
                          uint256 amount1Min;
                          address recipient;
                      }
                      /// @notice Calls the position manager's mint function
                      /// @param params Calldata to pass along to the position manager
                      /// @return result The result from the call
                      function mint(MintParams calldata params) external payable returns (bytes memory result);
                      struct IncreaseLiquidityParams {
                          address token0;
                          address token1;
                          uint256 tokenId;
                          uint256 amount0Min;
                          uint256 amount1Min;
                      }
                      /// @notice Calls the position manager's increaseLiquidity function
                      /// @param params Calldata to pass along to the position manager
                      /// @return result The result from the call
                      function increaseLiquidity(IncreaseLiquidityParams calldata params) external payable returns (bytes memory result);
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.7.5;
                  pragma abicoder v2;
                  import '@uniswap/v3-periphery/contracts/interfaces/IMulticall.sol';
                  /// @title MulticallExtended interface
                  /// @notice Enables calling multiple methods in a single call to the contract with optional validation
                  interface IMulticallExtended is IMulticall {
                      /// @notice Call multiple functions in the current contract and return the data from all of them if they all succeed
                      /// @dev The `msg.value` should not be trusted for any method callable from multicall.
                      /// @param deadline The time by which this function must be called before failing
                      /// @param data The encoded function data for each of the calls to make to this contract
                      /// @return results The results from each of the calls passed in via data
                      function multicall(uint256 deadline, bytes[] calldata data) external payable returns (bytes[] memory results);
                      /// @notice Call multiple functions in the current contract and return the data from all of them if they all succeed
                      /// @dev The `msg.value` should not be trusted for any method callable from multicall.
                      /// @param previousBlockhash The expected parent blockHash
                      /// @param data The encoded function data for each of the calls to make to this contract
                      /// @return results The results from each of the calls passed in via data
                      function multicall(bytes32 previousBlockhash, bytes[] calldata data)
                          external
                          payable
                          returns (bytes[] memory results);
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.5.0;
                  /// @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;
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.7.5;
                  pragma abicoder v2;
                  /// @title Multicall interface
                  /// @notice Enables calling multiple methods in a single call to the contract
                  interface IMulticall {
                      /// @notice Call multiple functions in the current contract and return the data from all of them if they all succeed
                      /// @dev The `msg.value` should not be trusted for any method callable from multicall.
                      /// @param data The encoded function data for each of the calls to make to this contract
                      /// @return results The results from each of the calls passed in via data
                      function multicall(bytes[] calldata data) external payable returns (bytes[] memory results);
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.7.0;
                  /// @title Optimized overflow and underflow safe math operations
                  /// @notice Contains methods for doing math operations that revert on overflow or underflow for minimal gas cost
                  library LowGasSafeMath {
                      /// @notice Returns x + y, reverts if sum overflows uint256
                      /// @param x The augend
                      /// @param y The addend
                      /// @return z The sum of x and y
                      function add(uint256 x, uint256 y) internal pure returns (uint256 z) {
                          require((z = x + y) >= x);
                      }
                      /// @notice Returns x - y, reverts if underflows
                      /// @param x The minuend
                      /// @param y The subtrahend
                      /// @return z The difference of x and y
                      function sub(uint256 x, uint256 y) internal pure returns (uint256 z) {
                          require((z = x - y) <= x);
                      }
                      /// @notice Returns x * y, reverts if overflows
                      /// @param x The multiplicand
                      /// @param y The multiplier
                      /// @return z The product of x and y
                      function mul(uint256 x, uint256 y) internal pure returns (uint256 z) {
                          require(x == 0 || (z = x * y) / x == y);
                      }
                      /// @notice Returns x + y, reverts if overflows or underflows
                      /// @param x The augend
                      /// @param y The addend
                      /// @return z The sum of x and y
                      function add(int256 x, int256 y) internal pure returns (int256 z) {
                          require((z = x + y) >= x == (y >= 0));
                      }
                      /// @notice Returns x - y, reverts if overflows or underflows
                      /// @param x The minuend
                      /// @param y The subtrahend
                      /// @return z The difference of x and y
                      function sub(int256 x, int256 y) internal pure returns (int256 z) {
                          require((z = x - y) <= x == (y >= 0));
                      }
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity =0.7.6;
                  import '../interfaces/IImmutableState.sol';
                  /// @title Immutable state
                  /// @notice Immutable state used by the swap router
                  abstract contract ImmutableState is IImmutableState {
                      /// @inheritdoc IImmutableState
                      address public immutable override factoryV2;
                      /// @inheritdoc IImmutableState
                      address public immutable override positionManager;
                      constructor(address _factoryV2, address _positionManager) {
                          factoryV2 = _factoryV2;
                          positionManager = _positionManager;
                      }
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.7.5;
                  import '@uniswap/v3-periphery/contracts/base/PeripheryPaymentsWithFee.sol';
                  import '../interfaces/IPeripheryPaymentsWithFeeExtended.sol';
                  import './PeripheryPaymentsExtended.sol';
                  abstract contract PeripheryPaymentsWithFeeExtended is
                      IPeripheryPaymentsWithFeeExtended,
                      PeripheryPaymentsExtended,
                      PeripheryPaymentsWithFee
                  {
                      /// @inheritdoc IPeripheryPaymentsWithFeeExtended
                      function unwrapWETH9WithFee(
                          uint256 amountMinimum,
                          uint256 feeBips,
                          address feeRecipient
                      ) external payable override {
                          unwrapWETH9WithFee(amountMinimum, msg.sender, feeBips, feeRecipient);
                      }
                      /// @inheritdoc IPeripheryPaymentsWithFeeExtended
                      function sweepTokenWithFee(
                          address token,
                          uint256 amountMinimum,
                          uint256 feeBips,
                          address feeRecipient
                      ) external payable override {
                          sweepTokenWithFee(token, amountMinimum, msg.sender, feeBips, feeRecipient);
                      }
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity =0.7.6;
                  /// @title Constant state
                  /// @notice Constant state used by the swap router
                  library Constants {
                      /// @dev Used for identifying cases when this contract's balance of a token is to be used
                      uint256 internal constant CONTRACT_BALANCE = 0;
                      /// @dev Used as a flag for identifying msg.sender, saves gas by sending more 0 bytes
                      address internal constant MSG_SENDER = address(1);
                      /// @dev Used as a flag for identifying address(this), saves gas by sending more 0 bytes
                      address internal constant ADDRESS_THIS = address(2);
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.5.0;
                  import '@uniswap/v2-core/contracts/interfaces/IUniswapV2Pair.sol';
                  import '@uniswap/v3-core/contracts/libraries/LowGasSafeMath.sol';
                  library UniswapV2Library {
                      using LowGasSafeMath for uint256;
                      // returns sorted token addresses, used to handle return values from pairs sorted in this order
                      function sortTokens(address tokenA, address tokenB) internal pure returns (address token0, address token1) {
                          require(tokenA != tokenB);
                          (token0, token1) = tokenA < tokenB ? (tokenA, tokenB) : (tokenB, tokenA);
                          require(token0 != address(0));
                      }
                      // calculates the CREATE2 address for a pair without making any external calls
                      function pairFor(
                          address factory,
                          address tokenA,
                          address tokenB
                      ) internal pure returns (address pair) {
                          (address token0, address token1) = sortTokens(tokenA, tokenB);
                          pair = address(
                              uint256(
                                  keccak256(
                                      abi.encodePacked(
                                          hex'ff',
                                          factory,
                                          keccak256(abi.encodePacked(token0, token1)),
                                          hex'96e8ac4277198ff8b6f785478aa9a39f403cb768dd02cbee326c3e7da348845f' // init code hash
                                      )
                                  )
                              )
                          );
                      }
                      // fetches and sorts the reserves for a pair
                      function getReserves(
                          address factory,
                          address tokenA,
                          address tokenB
                      ) internal view returns (uint256 reserveA, uint256 reserveB) {
                          (address token0, ) = sortTokens(tokenA, tokenB);
                          (uint256 reserve0, uint256 reserve1, ) = IUniswapV2Pair(pairFor(factory, tokenA, tokenB)).getReserves();
                          (reserveA, reserveB) = tokenA == token0 ? (reserve0, reserve1) : (reserve1, reserve0);
                      }
                      // given an input amount of an asset and pair reserves, returns the maximum output amount of the other asset
                      function getAmountOut(
                          uint256 amountIn,
                          uint256 reserveIn,
                          uint256 reserveOut
                      ) internal pure returns (uint256 amountOut) {
                          require(amountIn > 0, 'INSUFFICIENT_INPUT_AMOUNT');
                          require(reserveIn > 0 && reserveOut > 0);
                          uint256 amountInWithFee = amountIn.mul(997);
                          uint256 numerator = amountInWithFee.mul(reserveOut);
                          uint256 denominator = reserveIn.mul(1000).add(amountInWithFee);
                          amountOut = numerator / denominator;
                      }
                      // given an output amount of an asset and pair reserves, returns a required input amount of the other asset
                      function getAmountIn(
                          uint256 amountOut,
                          uint256 reserveIn,
                          uint256 reserveOut
                      ) internal pure returns (uint256 amountIn) {
                          require(amountOut > 0, 'INSUFFICIENT_OUTPUT_AMOUNT');
                          require(reserveIn > 0 && reserveOut > 0);
                          uint256 numerator = reserveIn.mul(amountOut).mul(1000);
                          uint256 denominator = reserveOut.sub(amountOut).mul(997);
                          amountIn = (numerator / denominator).add(1);
                      }
                      // performs chained getAmountIn calculations on any number of pairs
                      function getAmountsIn(
                          address factory,
                          uint256 amountOut,
                          address[] memory path
                      ) internal view returns (uint256[] memory amounts) {
                          require(path.length >= 2);
                          amounts = new uint256[](path.length);
                          amounts[amounts.length - 1] = amountOut;
                          for (uint256 i = path.length - 1; i > 0; i--) {
                              (uint256 reserveIn, uint256 reserveOut) = getReserves(factory, path[i - 1], path[i]);
                              amounts[i - 1] = getAmountIn(amounts[i], reserveIn, reserveOut);
                          }
                      }
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.5.0;
                  /// @title Immutable state
                  /// @notice Functions that return immutable state of the router
                  interface IImmutableState {
                      /// @return Returns the address of the Uniswap V2 factory
                      function factoryV2() external view returns (address);
                      /// @return Returns the address of Uniswap V3 NFT position manager
                      function positionManager() external view returns (address);
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.7.5;
                  import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
                  import '@uniswap/v3-core/contracts/libraries/LowGasSafeMath.sol';
                  import './PeripheryPayments.sol';
                  import '../interfaces/IPeripheryPaymentsWithFee.sol';
                  import '../interfaces/external/IWETH9.sol';
                  import '../libraries/TransferHelper.sol';
                  abstract contract PeripheryPaymentsWithFee is PeripheryPayments, IPeripheryPaymentsWithFee {
                      using LowGasSafeMath for uint256;
                      /// @inheritdoc IPeripheryPaymentsWithFee
                      function unwrapWETH9WithFee(
                          uint256 amountMinimum,
                          address recipient,
                          uint256 feeBips,
                          address feeRecipient
                      ) public payable override {
                          require(feeBips > 0 && feeBips <= 100);
                          uint256 balanceWETH9 = IWETH9(WETH9).balanceOf(address(this));
                          require(balanceWETH9 >= amountMinimum, 'Insufficient WETH9');
                          if (balanceWETH9 > 0) {
                              IWETH9(WETH9).withdraw(balanceWETH9);
                              uint256 feeAmount = balanceWETH9.mul(feeBips) / 10_000;
                              if (feeAmount > 0) TransferHelper.safeTransferETH(feeRecipient, feeAmount);
                              TransferHelper.safeTransferETH(recipient, balanceWETH9 - feeAmount);
                          }
                      }
                      /// @inheritdoc IPeripheryPaymentsWithFee
                      function sweepTokenWithFee(
                          address token,
                          uint256 amountMinimum,
                          address recipient,
                          uint256 feeBips,
                          address feeRecipient
                      ) public payable override {
                          require(feeBips > 0 && feeBips <= 100);
                          uint256 balanceToken = IERC20(token).balanceOf(address(this));
                          require(balanceToken >= amountMinimum, 'Insufficient token');
                          if (balanceToken > 0) {
                              uint256 feeAmount = balanceToken.mul(feeBips) / 10_000;
                              if (feeAmount > 0) TransferHelper.safeTransfer(token, feeRecipient, feeAmount);
                              TransferHelper.safeTransfer(token, recipient, balanceToken - feeAmount);
                          }
                      }
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.7.5;
                  import '@uniswap/v3-periphery/contracts/interfaces/IPeripheryPaymentsWithFee.sol';
                  import './IPeripheryPaymentsExtended.sol';
                  /// @title Periphery Payments With Fee Extended
                  /// @notice Functions to ease deposits and withdrawals of ETH
                  interface IPeripheryPaymentsWithFeeExtended is IPeripheryPaymentsExtended, IPeripheryPaymentsWithFee {
                      /// @notice Unwraps the contract's WETH9 balance and sends it to msg.sender as ETH, with a percentage between
                      /// 0 (exclusive), and 1 (inclusive) going to feeRecipient
                      /// @dev The amountMinimum parameter prevents malicious contracts from stealing WETH9 from users.
                      function unwrapWETH9WithFee(
                          uint256 amountMinimum,
                          uint256 feeBips,
                          address feeRecipient
                      ) external payable;
                      /// @notice Transfers the full amount of a token held by this contract to msg.sender, with a percentage between
                      /// 0 (exclusive) and 1 (inclusive) going to feeRecipient
                      /// @dev The amountMinimum parameter prevents malicious contracts from stealing the token from users
                      function sweepTokenWithFee(
                          address token,
                          uint256 amountMinimum,
                          uint256 feeBips,
                          address feeRecipient
                      ) external payable;
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.7.5;
                  import '@uniswap/v3-periphery/contracts/base/PeripheryPayments.sol';
                  import '@uniswap/v3-periphery/contracts/libraries/TransferHelper.sol';
                  import '../interfaces/IPeripheryPaymentsExtended.sol';
                  abstract contract PeripheryPaymentsExtended is IPeripheryPaymentsExtended, PeripheryPayments {
                      /// @inheritdoc IPeripheryPaymentsExtended
                      function unwrapWETH9(uint256 amountMinimum) external payable override {
                          unwrapWETH9(amountMinimum, msg.sender);
                      }
                      /// @inheritdoc IPeripheryPaymentsExtended
                      function wrapETH(uint256 value) external payable override {
                          IWETH9(WETH9).deposit{value: value}();
                      }
                      /// @inheritdoc IPeripheryPaymentsExtended
                      function sweepToken(address token, uint256 amountMinimum) external payable override {
                          sweepToken(token, amountMinimum, msg.sender);
                      }
                      /// @inheritdoc IPeripheryPaymentsExtended
                      function pull(address token, uint256 value) external payable override {
                          TransferHelper.safeTransferFrom(token, msg.sender, address(this), value);
                      }
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.7.5;
                  import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
                  import '../interfaces/IPeripheryPayments.sol';
                  import '../interfaces/external/IWETH9.sol';
                  import '../libraries/TransferHelper.sol';
                  import './PeripheryImmutableState.sol';
                  abstract contract PeripheryPayments is IPeripheryPayments, PeripheryImmutableState {
                      receive() external payable {
                          require(msg.sender == WETH9, 'Not WETH9');
                      }
                      /// @inheritdoc IPeripheryPayments
                      function unwrapWETH9(uint256 amountMinimum, address recipient) public payable override {
                          uint256 balanceWETH9 = IWETH9(WETH9).balanceOf(address(this));
                          require(balanceWETH9 >= amountMinimum, 'Insufficient WETH9');
                          if (balanceWETH9 > 0) {
                              IWETH9(WETH9).withdraw(balanceWETH9);
                              TransferHelper.safeTransferETH(recipient, balanceWETH9);
                          }
                      }
                      /// @inheritdoc IPeripheryPayments
                      function sweepToken(
                          address token,
                          uint256 amountMinimum,
                          address recipient
                      ) public payable override {
                          uint256 balanceToken = IERC20(token).balanceOf(address(this));
                          require(balanceToken >= amountMinimum, 'Insufficient token');
                          if (balanceToken > 0) {
                              TransferHelper.safeTransfer(token, recipient, balanceToken);
                          }
                      }
                      /// @inheritdoc IPeripheryPayments
                      function refundETH() external payable override {
                          if (address(this).balance > 0) TransferHelper.safeTransferETH(msg.sender, address(this).balance);
                      }
                      /// @param token The token to pay
                      /// @param payer The entity that must pay
                      /// @param recipient The entity that will receive payment
                      /// @param value The amount to pay
                      function pay(
                          address token,
                          address payer,
                          address recipient,
                          uint256 value
                      ) internal {
                          if (token == WETH9 && address(this).balance >= value) {
                              // pay with WETH9
                              IWETH9(WETH9).deposit{value: value}(); // wrap only what is needed to pay
                              IWETH9(WETH9).transfer(recipient, value);
                          } else if (payer == address(this)) {
                              // pay with tokens already in the contract (for the exact input multihop case)
                              TransferHelper.safeTransfer(token, recipient, value);
                          } else {
                              // pull payment
                              TransferHelper.safeTransferFrom(token, payer, recipient, value);
                          }
                      }
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.7.5;
                  import './IPeripheryPayments.sol';
                  /// @title Periphery Payments
                  /// @notice Functions to ease deposits and withdrawals of ETH
                  interface IPeripheryPaymentsWithFee is IPeripheryPayments {
                      /// @notice Unwraps the contract's WETH9 balance and sends it to recipient as ETH, with a percentage between
                      /// 0 (exclusive), and 1 (inclusive) going to feeRecipient
                      /// @dev The amountMinimum parameter prevents malicious contracts from stealing WETH9 from users.
                      function unwrapWETH9WithFee(
                          uint256 amountMinimum,
                          address recipient,
                          uint256 feeBips,
                          address feeRecipient
                      ) external payable;
                      /// @notice Transfers the full amount of a token held by this contract to recipient, with a percentage between
                      /// 0 (exclusive) and 1 (inclusive) going to feeRecipient
                      /// @dev The amountMinimum parameter prevents malicious contracts from stealing the token from users
                      function sweepTokenWithFee(
                          address token,
                          uint256 amountMinimum,
                          address recipient,
                          uint256 feeBips,
                          address feeRecipient
                      ) external payable;
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity =0.7.6;
                  import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
                  /// @title Interface for WETH9
                  interface IWETH9 is IERC20 {
                      /// @notice Deposit ether to get wrapped ether
                      function deposit() external payable;
                      /// @notice Withdraw wrapped ether to get ether
                      function withdraw(uint256) external;
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.6.0;
                  import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
                  library TransferHelper {
                      /// @notice Transfers tokens from the targeted address to the given destination
                      /// @notice Errors with 'STF' if transfer fails
                      /// @param token The contract address of the token to be transferred
                      /// @param from The originating address from which the tokens will be transferred
                      /// @param to The destination address of the transfer
                      /// @param value The amount to be transferred
                      function safeTransferFrom(
                          address token,
                          address from,
                          address to,
                          uint256 value
                      ) internal {
                          (bool success, bytes memory data) =
                              token.call(abi.encodeWithSelector(IERC20.transferFrom.selector, from, to, value));
                          require(success && (data.length == 0 || abi.decode(data, (bool))), 'STF');
                      }
                      /// @notice Transfers tokens from msg.sender to a recipient
                      /// @dev Errors with ST if transfer fails
                      /// @param token The contract address of the token which will be transferred
                      /// @param to The recipient of the transfer
                      /// @param value The value of the transfer
                      function safeTransfer(
                          address token,
                          address to,
                          uint256 value
                      ) internal {
                          (bool success, bytes memory data) = token.call(abi.encodeWithSelector(IERC20.transfer.selector, to, value));
                          require(success && (data.length == 0 || abi.decode(data, (bool))), 'ST');
                      }
                      /// @notice Approves the stipulated contract to spend the given allowance in the given token
                      /// @dev Errors with 'SA' if transfer fails
                      /// @param token The contract address of the token to be approved
                      /// @param to The target of the approval
                      /// @param value The amount of the given token the target will be allowed to spend
                      function safeApprove(
                          address token,
                          address to,
                          uint256 value
                      ) internal {
                          (bool success, bytes memory data) = token.call(abi.encodeWithSelector(IERC20.approve.selector, to, value));
                          require(success && (data.length == 0 || abi.decode(data, (bool))), 'SA');
                      }
                      /// @notice Transfers ETH to the recipient address
                      /// @dev Fails with `STE`
                      /// @param to The destination of the transfer
                      /// @param value The value to be transferred
                      function safeTransferETH(address to, uint256 value) internal {
                          (bool success, ) = to.call{value: value}(new bytes(0));
                          require(success, 'STE');
                      }
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.7.5;
                  /// @title Periphery Payments
                  /// @notice Functions to ease deposits and withdrawals of ETH
                  interface IPeripheryPayments {
                      /// @notice Unwraps the contract's WETH9 balance and sends it to recipient as ETH.
                      /// @dev The amountMinimum parameter prevents malicious contracts from stealing WETH9 from users.
                      /// @param amountMinimum The minimum amount of WETH9 to unwrap
                      /// @param recipient The address receiving ETH
                      function unwrapWETH9(uint256 amountMinimum, address recipient) external payable;
                      /// @notice Refunds any ETH balance held by this contract to the `msg.sender`
                      /// @dev Useful for bundling with mint or increase liquidity that uses ether, or exact output swaps
                      /// that use ether for the input amount
                      function refundETH() external payable;
                      /// @notice Transfers the full amount of a token held by this contract to recipient
                      /// @dev The amountMinimum parameter prevents malicious contracts from stealing the token from users
                      /// @param token The contract address of the token which will be transferred to `recipient`
                      /// @param amountMinimum The minimum amount of token required for a transfer
                      /// @param recipient The destination address of the token
                      function sweepToken(
                          address token,
                          uint256 amountMinimum,
                          address recipient
                      ) external payable;
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.7.5;
                  import '@uniswap/v3-periphery/contracts/interfaces/IPeripheryPayments.sol';
                  /// @title Periphery Payments Extended
                  /// @notice Functions to ease deposits and withdrawals of ETH and tokens
                  interface IPeripheryPaymentsExtended is IPeripheryPayments {
                      /// @notice Unwraps the contract's WETH9 balance and sends it to msg.sender as ETH.
                      /// @dev The amountMinimum parameter prevents malicious contracts from stealing WETH9 from users.
                      /// @param amountMinimum The minimum amount of WETH9 to unwrap
                      function unwrapWETH9(uint256 amountMinimum) external payable;
                      /// @notice Wraps the contract's ETH balance into WETH9
                      /// @dev The resulting WETH9 is custodied by the router, thus will require further distribution
                      /// @param value The amount of ETH to wrap
                      function wrapETH(uint256 value) external payable;
                      /// @notice Transfers the full amount of a token held by this contract to msg.sender
                      /// @dev The amountMinimum parameter prevents malicious contracts from stealing the token from users
                      /// @param token The contract address of the token which will be transferred to msg.sender
                      /// @param amountMinimum The minimum amount of token required for a transfer
                      function sweepToken(address token, uint256 amountMinimum) external payable;
                      /// @notice Transfers the specified amount of a token from the msg.sender to address(this)
                      /// @param token The token to pull
                      /// @param value The amount to pay
                      function pull(address token, uint256 value) external payable;
                  }
                  pragma solidity >=0.5.0;
                  interface IUniswapV2Pair {
                      event Approval(address indexed owner, address indexed spender, uint value);
                      event Transfer(address indexed from, address indexed to, uint value);
                      function name() external pure returns (string memory);
                      function symbol() external pure returns (string memory);
                      function decimals() external pure returns (uint8);
                      function totalSupply() external view returns (uint);
                      function balanceOf(address owner) external view returns (uint);
                      function allowance(address owner, address spender) external view returns (uint);
                      function approve(address spender, uint value) external returns (bool);
                      function transfer(address to, uint value) external returns (bool);
                      function transferFrom(address from, address to, uint value) external returns (bool);
                      function DOMAIN_SEPARATOR() external view returns (bytes32);
                      function PERMIT_TYPEHASH() external pure returns (bytes32);
                      function nonces(address owner) external view returns (uint);
                      function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external;
                      event Mint(address indexed sender, uint amount0, uint amount1);
                      event Burn(address indexed sender, uint amount0, uint amount1, address indexed to);
                      event Swap(
                          address indexed sender,
                          uint amount0In,
                          uint amount1In,
                          uint amount0Out,
                          uint amount1Out,
                          address indexed to
                      );
                      event Sync(uint112 reserve0, uint112 reserve1);
                      function MINIMUM_LIQUIDITY() external pure returns (uint);
                      function factory() external view returns (address);
                      function token0() external view returns (address);
                      function token1() external view returns (address);
                      function getReserves() external view returns (uint112 reserve0, uint112 reserve1, uint32 blockTimestampLast);
                      function price0CumulativeLast() external view returns (uint);
                      function price1CumulativeLast() external view returns (uint);
                      function kLast() external view returns (uint);
                      function mint(address to) external returns (uint liquidity);
                      function burn(address to) external returns (uint amount0, uint amount1);
                      function swap(uint amount0Out, uint amount1Out, address to, bytes calldata data) external;
                      function skim(address to) external;
                      function sync() external;
                      function initialize(address, address) external;
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.5.0;
                  /// @title Safe casting methods
                  /// @notice Contains methods for safely casting between types
                  library SafeCast {
                      /// @notice Cast a uint256 to a uint160, revert on overflow
                      /// @param y The uint256 to be downcasted
                      /// @return z The downcasted integer, now type uint160
                      function toUint160(uint256 y) internal pure returns (uint160 z) {
                          require((z = uint160(y)) == y);
                      }
                      /// @notice Cast a int256 to a int128, revert on overflow or underflow
                      /// @param y The int256 to be downcasted
                      /// @return z The downcasted integer, now type int128
                      function toInt128(int256 y) internal pure returns (int128 z) {
                          require((z = int128(y)) == y);
                      }
                      /// @notice Cast a uint256 to a int256, revert on overflow
                      /// @param y The uint256 to be casted
                      /// @return z The casted integer, now type int256
                      function toInt256(uint256 y) internal pure returns (int256 z) {
                          require(y < 2**255);
                          z = int256(y);
                      }
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.5.0;
                  /// @title Math library for computing sqrt prices from ticks and vice versa
                  /// @notice Computes sqrt price for ticks of size 1.0001, i.e. sqrt(1.0001^tick) as fixed point Q64.96 numbers. Supports
                  /// prices between 2**-128 and 2**128
                  library TickMath {
                      /// @dev The minimum tick that may be passed to #getSqrtRatioAtTick computed from log base 1.0001 of 2**-128
                      int24 internal constant MIN_TICK = -887272;
                      /// @dev The maximum tick that may be passed to #getSqrtRatioAtTick computed from log base 1.0001 of 2**128
                      int24 internal constant MAX_TICK = -MIN_TICK;
                      /// @dev The minimum value that can be returned from #getSqrtRatioAtTick. Equivalent to getSqrtRatioAtTick(MIN_TICK)
                      uint160 internal constant MIN_SQRT_RATIO = 4295128739;
                      /// @dev The maximum value that can be returned from #getSqrtRatioAtTick. Equivalent to getSqrtRatioAtTick(MAX_TICK)
                      uint160 internal constant MAX_SQRT_RATIO = 1461446703485210103287273052203988822378723970342;
                      /// @notice Calculates sqrt(1.0001^tick) * 2^96
                      /// @dev Throws if |tick| > max tick
                      /// @param tick The input tick for the above formula
                      /// @return sqrtPriceX96 A Fixed point Q64.96 number representing the sqrt of the ratio of the two assets (token1/token0)
                      /// at the given tick
                      function getSqrtRatioAtTick(int24 tick) internal pure returns (uint160 sqrtPriceX96) {
                          uint256 absTick = tick < 0 ? uint256(-int256(tick)) : uint256(int256(tick));
                          require(absTick <= uint256(MAX_TICK), 'T');
                          uint256 ratio = absTick & 0x1 != 0 ? 0xfffcb933bd6fad37aa2d162d1a594001 : 0x100000000000000000000000000000000;
                          if (absTick & 0x2 != 0) ratio = (ratio * 0xfff97272373d413259a46990580e213a) >> 128;
                          if (absTick & 0x4 != 0) ratio = (ratio * 0xfff2e50f5f656932ef12357cf3c7fdcc) >> 128;
                          if (absTick & 0x8 != 0) ratio = (ratio * 0xffe5caca7e10e4e61c3624eaa0941cd0) >> 128;
                          if (absTick & 0x10 != 0) ratio = (ratio * 0xffcb9843d60f6159c9db58835c926644) >> 128;
                          if (absTick & 0x20 != 0) ratio = (ratio * 0xff973b41fa98c081472e6896dfb254c0) >> 128;
                          if (absTick & 0x40 != 0) ratio = (ratio * 0xff2ea16466c96a3843ec78b326b52861) >> 128;
                          if (absTick & 0x80 != 0) ratio = (ratio * 0xfe5dee046a99a2a811c461f1969c3053) >> 128;
                          if (absTick & 0x100 != 0) ratio = (ratio * 0xfcbe86c7900a88aedcffc83b479aa3a4) >> 128;
                          if (absTick & 0x200 != 0) ratio = (ratio * 0xf987a7253ac413176f2b074cf7815e54) >> 128;
                          if (absTick & 0x400 != 0) ratio = (ratio * 0xf3392b0822b70005940c7a398e4b70f3) >> 128;
                          if (absTick & 0x800 != 0) ratio = (ratio * 0xe7159475a2c29b7443b29c7fa6e889d9) >> 128;
                          if (absTick & 0x1000 != 0) ratio = (ratio * 0xd097f3bdfd2022b8845ad8f792aa5825) >> 128;
                          if (absTick & 0x2000 != 0) ratio = (ratio * 0xa9f746462d870fdf8a65dc1f90e061e5) >> 128;
                          if (absTick & 0x4000 != 0) ratio = (ratio * 0x70d869a156d2a1b890bb3df62baf32f7) >> 128;
                          if (absTick & 0x8000 != 0) ratio = (ratio * 0x31be135f97d08fd981231505542fcfa6) >> 128;
                          if (absTick & 0x10000 != 0) ratio = (ratio * 0x9aa508b5b7a84e1c677de54f3e99bc9) >> 128;
                          if (absTick & 0x20000 != 0) ratio = (ratio * 0x5d6af8dedb81196699c329225ee604) >> 128;
                          if (absTick & 0x40000 != 0) ratio = (ratio * 0x2216e584f5fa1ea926041bedfe98) >> 128;
                          if (absTick & 0x80000 != 0) ratio = (ratio * 0x48a170391f7dc42444e8fa2) >> 128;
                          if (tick > 0) ratio = type(uint256).max / ratio;
                          // this divides by 1<<32 rounding up to go from a Q128.128 to a Q128.96.
                          // we then downcast because we know the result always fits within 160 bits due to our tick input constraint
                          // we round up in the division so getTickAtSqrtRatio of the output price is always consistent
                          sqrtPriceX96 = uint160((ratio >> 32) + (ratio % (1 << 32) == 0 ? 0 : 1));
                      }
                      /// @notice Calculates the greatest tick value such that getRatioAtTick(tick) <= ratio
                      /// @dev Throws in case sqrtPriceX96 < MIN_SQRT_RATIO, as MIN_SQRT_RATIO is the lowest value getRatioAtTick may
                      /// ever return.
                      /// @param sqrtPriceX96 The sqrt ratio for which to compute the tick as a Q64.96
                      /// @return tick The greatest tick for which the ratio is less than or equal to the input ratio
                      function getTickAtSqrtRatio(uint160 sqrtPriceX96) internal pure returns (int24 tick) {
                          // second inequality must be < because the price can never reach the price at the max tick
                          require(sqrtPriceX96 >= MIN_SQRT_RATIO && sqrtPriceX96 < MAX_SQRT_RATIO, 'R');
                          uint256 ratio = uint256(sqrtPriceX96) << 32;
                          uint256 r = ratio;
                          uint256 msb = 0;
                          assembly {
                              let f := shl(7, gt(r, 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF))
                              msb := or(msb, f)
                              r := shr(f, r)
                          }
                          assembly {
                              let f := shl(6, gt(r, 0xFFFFFFFFFFFFFFFF))
                              msb := or(msb, f)
                              r := shr(f, r)
                          }
                          assembly {
                              let f := shl(5, gt(r, 0xFFFFFFFF))
                              msb := or(msb, f)
                              r := shr(f, r)
                          }
                          assembly {
                              let f := shl(4, gt(r, 0xFFFF))
                              msb := or(msb, f)
                              r := shr(f, r)
                          }
                          assembly {
                              let f := shl(3, gt(r, 0xFF))
                              msb := or(msb, f)
                              r := shr(f, r)
                          }
                          assembly {
                              let f := shl(2, gt(r, 0xF))
                              msb := or(msb, f)
                              r := shr(f, r)
                          }
                          assembly {
                              let f := shl(1, gt(r, 0x3))
                              msb := or(msb, f)
                              r := shr(f, r)
                          }
                          assembly {
                              let f := gt(r, 0x1)
                              msb := or(msb, f)
                          }
                          if (msb >= 128) r = ratio >> (msb - 127);
                          else r = ratio << (127 - msb);
                          int256 log_2 = (int256(msb) - 128) << 64;
                          assembly {
                              r := shr(127, mul(r, r))
                              let f := shr(128, r)
                              log_2 := or(log_2, shl(63, f))
                              r := shr(f, r)
                          }
                          assembly {
                              r := shr(127, mul(r, r))
                              let f := shr(128, r)
                              log_2 := or(log_2, shl(62, f))
                              r := shr(f, r)
                          }
                          assembly {
                              r := shr(127, mul(r, r))
                              let f := shr(128, r)
                              log_2 := or(log_2, shl(61, f))
                              r := shr(f, r)
                          }
                          assembly {
                              r := shr(127, mul(r, r))
                              let f := shr(128, r)
                              log_2 := or(log_2, shl(60, f))
                              r := shr(f, r)
                          }
                          assembly {
                              r := shr(127, mul(r, r))
                              let f := shr(128, r)
                              log_2 := or(log_2, shl(59, f))
                              r := shr(f, r)
                          }
                          assembly {
                              r := shr(127, mul(r, r))
                              let f := shr(128, r)
                              log_2 := or(log_2, shl(58, f))
                              r := shr(f, r)
                          }
                          assembly {
                              r := shr(127, mul(r, r))
                              let f := shr(128, r)
                              log_2 := or(log_2, shl(57, f))
                              r := shr(f, r)
                          }
                          assembly {
                              r := shr(127, mul(r, r))
                              let f := shr(128, r)
                              log_2 := or(log_2, shl(56, f))
                              r := shr(f, r)
                          }
                          assembly {
                              r := shr(127, mul(r, r))
                              let f := shr(128, r)
                              log_2 := or(log_2, shl(55, f))
                              r := shr(f, r)
                          }
                          assembly {
                              r := shr(127, mul(r, r))
                              let f := shr(128, r)
                              log_2 := or(log_2, shl(54, f))
                              r := shr(f, r)
                          }
                          assembly {
                              r := shr(127, mul(r, r))
                              let f := shr(128, r)
                              log_2 := or(log_2, shl(53, f))
                              r := shr(f, r)
                          }
                          assembly {
                              r := shr(127, mul(r, r))
                              let f := shr(128, r)
                              log_2 := or(log_2, shl(52, f))
                              r := shr(f, r)
                          }
                          assembly {
                              r := shr(127, mul(r, r))
                              let f := shr(128, r)
                              log_2 := or(log_2, shl(51, f))
                              r := shr(f, r)
                          }
                          assembly {
                              r := shr(127, mul(r, r))
                              let f := shr(128, r)
                              log_2 := or(log_2, shl(50, f))
                          }
                          int256 log_sqrt10001 = log_2 * 255738958999603826347141; // 128.128 number
                          int24 tickLow = int24((log_sqrt10001 - 3402992956809132418596140100660247210) >> 128);
                          int24 tickHi = int24((log_sqrt10001 + 291339464771989622907027621153398088495) >> 128);
                          tick = tickLow == tickHi ? tickLow : getSqrtRatioAtTick(tickHi) <= sqrtPriceX96 ? tickHi : tickLow;
                      }
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.5.0;
                  import './pool/IUniswapV3PoolImmutables.sol';
                  import './pool/IUniswapV3PoolState.sol';
                  import './pool/IUniswapV3PoolDerivedState.sol';
                  import './pool/IUniswapV3PoolActions.sol';
                  import './pool/IUniswapV3PoolOwnerActions.sol';
                  import './pool/IUniswapV3PoolEvents.sol';
                  /// @title The interface for a Uniswap V3 Pool
                  /// @notice A Uniswap pool facilitates swapping and automated market making between any two assets that strictly conform
                  /// to the ERC20 specification
                  /// @dev The pool interface is broken up into many smaller pieces
                  interface IUniswapV3Pool is
                      IUniswapV3PoolImmutables,
                      IUniswapV3PoolState,
                      IUniswapV3PoolDerivedState,
                      IUniswapV3PoolActions,
                      IUniswapV3PoolOwnerActions,
                      IUniswapV3PoolEvents
                  {
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.6.0;
                  import './BytesLib.sol';
                  /// @title Functions for manipulating path data for multihop swaps
                  library Path {
                      using BytesLib for bytes;
                      /// @dev The length of the bytes encoded address
                      uint256 private constant ADDR_SIZE = 20;
                      /// @dev The length of the bytes encoded fee
                      uint256 private constant FEE_SIZE = 3;
                      /// @dev The offset of a single token address and pool fee
                      uint256 private constant NEXT_OFFSET = ADDR_SIZE + FEE_SIZE;
                      /// @dev The offset of an encoded pool key
                      uint256 private constant POP_OFFSET = NEXT_OFFSET + ADDR_SIZE;
                      /// @dev The minimum length of an encoding that contains 2 or more pools
                      uint256 private constant MULTIPLE_POOLS_MIN_LENGTH = POP_OFFSET + NEXT_OFFSET;
                      /// @notice Returns true iff the path contains two or more pools
                      /// @param path The encoded swap path
                      /// @return True if path contains two or more pools, otherwise false
                      function hasMultiplePools(bytes memory path) internal pure returns (bool) {
                          return path.length >= MULTIPLE_POOLS_MIN_LENGTH;
                      }
                      /// @notice Returns the number of pools in the path
                      /// @param path The encoded swap path
                      /// @return The number of pools in the path
                      function numPools(bytes memory path) internal pure returns (uint256) {
                          // Ignore the first token address. From then on every fee and token offset indicates a pool.
                          return ((path.length - ADDR_SIZE) / NEXT_OFFSET);
                      }
                      /// @notice Decodes the first pool in path
                      /// @param path The bytes encoded swap path
                      /// @return tokenA The first token of the given pool
                      /// @return tokenB The second token of the given pool
                      /// @return fee The fee level of the pool
                      function decodeFirstPool(bytes memory path)
                          internal
                          pure
                          returns (
                              address tokenA,
                              address tokenB,
                              uint24 fee
                          )
                      {
                          tokenA = path.toAddress(0);
                          fee = path.toUint24(ADDR_SIZE);
                          tokenB = path.toAddress(NEXT_OFFSET);
                      }
                      /// @notice Gets the segment corresponding to the first pool in the path
                      /// @param path The bytes encoded swap path
                      /// @return The segment containing all data necessary to target the first pool in the path
                      function getFirstPool(bytes memory path) internal pure returns (bytes memory) {
                          return path.slice(0, POP_OFFSET);
                      }
                      /// @notice Skips a token + fee element from the buffer and returns the remainder
                      /// @param path The swap path
                      /// @return The remaining token + fee elements in the path
                      function skipToken(bytes memory path) internal pure returns (bytes memory) {
                          return path.slice(NEXT_OFFSET, path.length - NEXT_OFFSET);
                      }
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.5.0;
                  /// @title Provides functions for deriving a pool address from the factory, tokens, and the fee
                  library PoolAddress {
                      bytes32 internal constant POOL_INIT_CODE_HASH = 0xe34f199b19b2b4f47f68442619d555527d244f78a3297ea89325f843f87b8b54;
                      /// @notice The identifying key of the pool
                      struct PoolKey {
                          address token0;
                          address token1;
                          uint24 fee;
                      }
                      /// @notice Returns PoolKey: the ordered tokens with the matched fee levels
                      /// @param tokenA The first token of a pool, unsorted
                      /// @param tokenB The second token of a pool, unsorted
                      /// @param fee The fee level of the pool
                      /// @return Poolkey The pool details with ordered token0 and token1 assignments
                      function getPoolKey(
                          address tokenA,
                          address tokenB,
                          uint24 fee
                      ) internal pure returns (PoolKey memory) {
                          if (tokenA > tokenB) (tokenA, tokenB) = (tokenB, tokenA);
                          return PoolKey({token0: tokenA, token1: tokenB, fee: fee});
                      }
                      /// @notice Deterministically computes the pool address given the factory and PoolKey
                      /// @param factory The Uniswap V3 factory contract address
                      /// @param key The PoolKey
                      /// @return pool The contract address of the V3 pool
                      function computeAddress(address factory, PoolKey memory key) internal pure returns (address pool) {
                          require(key.token0 < key.token1);
                          pool = address(
                              uint256(
                                  keccak256(
                                      abi.encodePacked(
                                          hex'ff',
                                          factory,
                                          keccak256(abi.encode(key.token0, key.token1, key.fee)),
                                          POOL_INIT_CODE_HASH
                                      )
                                  )
                              )
                          );
                      }
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity =0.7.6;
                  import '@uniswap/v3-core/contracts/interfaces/IUniswapV3Pool.sol';
                  import './PoolAddress.sol';
                  /// @notice Provides validation for callbacks from Uniswap V3 Pools
                  library CallbackValidation {
                      /// @notice Returns the address of a valid Uniswap V3 Pool
                      /// @param factory The contract address of the Uniswap V3 factory
                      /// @param tokenA The contract address of either token0 or token1
                      /// @param tokenB The contract address of the other token
                      /// @param fee The fee collected upon every swap in the pool, denominated in hundredths of a bip
                      /// @return pool The V3 pool contract address
                      function verifyCallback(
                          address factory,
                          address tokenA,
                          address tokenB,
                          uint24 fee
                      ) internal view returns (IUniswapV3Pool pool) {
                          return verifyCallback(factory, PoolAddress.getPoolKey(tokenA, tokenB, fee));
                      }
                      /// @notice Returns the address of a valid Uniswap V3 Pool
                      /// @param factory The contract address of the Uniswap V3 factory
                      /// @param poolKey The identifying key of the V3 pool
                      /// @return pool The V3 pool contract address
                      function verifyCallback(address factory, PoolAddress.PoolKey memory poolKey)
                          internal
                          view
                          returns (IUniswapV3Pool pool)
                      {
                          pool = IUniswapV3Pool(PoolAddress.computeAddress(factory, poolKey));
                          require(msg.sender == address(pool));
                      }
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity =0.7.6;
                  pragma abicoder v2;
                  import '../interfaces/IOracleSlippage.sol';
                  import '@uniswap/v3-periphery/contracts/base/PeripheryImmutableState.sol';
                  import '@uniswap/v3-periphery/contracts/base/BlockTimestamp.sol';
                  import '@uniswap/v3-periphery/contracts/libraries/Path.sol';
                  import '@uniswap/v3-periphery/contracts/libraries/PoolAddress.sol';
                  import '@uniswap/v3-core/contracts/interfaces/IUniswapV3Pool.sol';
                  import '@uniswap/v3-periphery/contracts/libraries/OracleLibrary.sol';
                  abstract contract OracleSlippage is IOracleSlippage, PeripheryImmutableState, BlockTimestamp {
                      using Path for bytes;
                      /// @dev Returns the tick as of the beginning of the current block, and as of right now, for the given pool.
                      function getBlockStartingAndCurrentTick(IUniswapV3Pool pool)
                          internal
                          view
                          returns (int24 blockStartingTick, int24 currentTick)
                      {
                          uint16 observationIndex;
                          uint16 observationCardinality;
                          (, currentTick, observationIndex, observationCardinality, , , ) = pool.slot0();
                          // 2 observations are needed to reliably calculate the block starting tick
                          require(observationCardinality > 1, 'NEO');
                          // If the latest observation occurred in the past, then no tick-changing trades have happened in this block
                          // therefore the tick in `slot0` is the same as at the beginning of the current block.
                          // We don't need to check if this observation is initialized - it is guaranteed to be.
                          (uint32 observationTimestamp, int56 tickCumulative, , ) = pool.observations(observationIndex);
                          if (observationTimestamp != uint32(_blockTimestamp())) {
                              blockStartingTick = currentTick;
                          } else {
                              uint256 prevIndex = (uint256(observationIndex) + observationCardinality - 1) % observationCardinality;
                              (uint32 prevObservationTimestamp, int56 prevTickCumulative, , bool prevInitialized) =
                                  pool.observations(prevIndex);
                              require(prevInitialized, 'ONI');
                              uint32 delta = observationTimestamp - prevObservationTimestamp;
                              blockStartingTick = int24((tickCumulative - prevTickCumulative) / delta);
                          }
                      }
                      /// @dev Virtual function to get pool addresses that can be overridden in tests.
                      function getPoolAddress(
                          address tokenA,
                          address tokenB,
                          uint24 fee
                      ) internal view virtual returns (IUniswapV3Pool pool) {
                          pool = IUniswapV3Pool(PoolAddress.computeAddress(factory, PoolAddress.getPoolKey(tokenA, tokenB, fee)));
                      }
                      /// @dev Returns the synthetic time-weighted average tick as of secondsAgo, as well as the current tick,
                      /// for the given path. Returned synthetic ticks always represent tokenOut/tokenIn prices,
                      /// meaning lower ticks are worse.
                      function getSyntheticTicks(bytes memory path, uint32 secondsAgo)
                          internal
                          view
                          returns (int256 syntheticAverageTick, int256 syntheticCurrentTick)
                      {
                          bool lowerTicksAreWorse;
                          uint256 numPools = path.numPools();
                          address previousTokenIn;
                          for (uint256 i = 0; i < numPools; i++) {
                              // this assumes the path is sorted in swap order
                              (address tokenIn, address tokenOut, uint24 fee) = path.decodeFirstPool();
                              IUniswapV3Pool pool = getPoolAddress(tokenIn, tokenOut, fee);
                              // get the average and current ticks for the current pool
                              int256 averageTick;
                              int256 currentTick;
                              if (secondsAgo == 0) {
                                  // we optimize for the secondsAgo == 0 case, i.e. since the beginning of the block
                                  (averageTick, currentTick) = getBlockStartingAndCurrentTick(pool);
                              } else {
                                  (averageTick, ) = OracleLibrary.consult(address(pool), secondsAgo);
                                  (, currentTick, , , , , ) = IUniswapV3Pool(pool).slot0();
                              }
                              if (i == numPools - 1) {
                                  // if we're here, this is the last pool in the path, meaning tokenOut represents the
                                  // destination token. so, if tokenIn < tokenOut, then tokenIn is token0 of the last pool,
                                  // meaning the current running ticks are going to represent tokenOut/tokenIn prices.
                                  // so, the lower these prices get, the worse of a price the swap will get
                                  lowerTicksAreWorse = tokenIn < tokenOut;
                              } else {
                                  // if we're here, we need to iterate over the next pool in the path
                                  path = path.skipToken();
                                  previousTokenIn = tokenIn;
                              }
                              // accumulate the ticks derived from the current pool into the running synthetic ticks,
                              // ensuring that intermediate tokens "cancel out"
                              bool add = (i == 0) || (previousTokenIn < tokenIn ? tokenIn < tokenOut : tokenOut < tokenIn);
                              if (add) {
                                  syntheticAverageTick += averageTick;
                                  syntheticCurrentTick += currentTick;
                              } else {
                                  syntheticAverageTick -= averageTick;
                                  syntheticCurrentTick -= currentTick;
                              }
                          }
                          // flip the sign of the ticks if necessary, to ensure that the lower ticks are always worse
                          if (!lowerTicksAreWorse) {
                              syntheticAverageTick *= -1;
                              syntheticCurrentTick *= -1;
                          }
                      }
                      /// @dev Cast a int256 to a int24, revert on overflow or underflow
                      function toInt24(int256 y) private pure returns (int24 z) {
                          require((z = int24(y)) == y);
                      }
                      /// @dev For each passed path, fetches the synthetic time-weighted average tick as of secondsAgo,
                      /// as well as the current tick. Then, synthetic ticks from all paths are subjected to a weighted
                      /// average, where the weights are the fraction of the total input amount allocated to each path.
                      /// Returned synthetic ticks always represent tokenOut/tokenIn prices, meaning lower ticks are worse.
                      /// Paths must all start and end in the same token.
                      function getSyntheticTicks(
                          bytes[] memory paths,
                          uint128[] memory amounts,
                          uint32 secondsAgo
                      ) internal view returns (int256 averageSyntheticAverageTick, int256 averageSyntheticCurrentTick) {
                          require(paths.length == amounts.length);
                          OracleLibrary.WeightedTickData[] memory weightedSyntheticAverageTicks =
                              new OracleLibrary.WeightedTickData[](paths.length);
                          OracleLibrary.WeightedTickData[] memory weightedSyntheticCurrentTicks =
                              new OracleLibrary.WeightedTickData[](paths.length);
                          for (uint256 i = 0; i < paths.length; i++) {
                              (int256 syntheticAverageTick, int256 syntheticCurrentTick) = getSyntheticTicks(paths[i], secondsAgo);
                              weightedSyntheticAverageTicks[i].tick = toInt24(syntheticAverageTick);
                              weightedSyntheticCurrentTicks[i].tick = toInt24(syntheticCurrentTick);
                              weightedSyntheticAverageTicks[i].weight = amounts[i];
                              weightedSyntheticCurrentTicks[i].weight = amounts[i];
                          }
                          averageSyntheticAverageTick = OracleLibrary.getWeightedArithmeticMeanTick(weightedSyntheticAverageTicks);
                          averageSyntheticCurrentTick = OracleLibrary.getWeightedArithmeticMeanTick(weightedSyntheticCurrentTicks);
                      }
                      /// @inheritdoc IOracleSlippage
                      function checkOracleSlippage(
                          bytes memory path,
                          uint24 maximumTickDivergence,
                          uint32 secondsAgo
                      ) external view override {
                          (int256 syntheticAverageTick, int256 syntheticCurrentTick) = getSyntheticTicks(path, secondsAgo);
                          require(syntheticAverageTick - syntheticCurrentTick < maximumTickDivergence, 'TD');
                      }
                      /// @inheritdoc IOracleSlippage
                      function checkOracleSlippage(
                          bytes[] memory paths,
                          uint128[] memory amounts,
                          uint24 maximumTickDivergence,
                          uint32 secondsAgo
                      ) external view override {
                          (int256 averageSyntheticAverageTick, int256 averageSyntheticCurrentTick) =
                              getSyntheticTicks(paths, amounts, secondsAgo);
                          require(averageSyntheticAverageTick - averageSyntheticCurrentTick < maximumTickDivergence, 'TD');
                      }
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.5.0;
                  /// @title Pool state that never changes
                  /// @notice These parameters are fixed for a pool forever, i.e., the methods will always return the same values
                  interface IUniswapV3PoolImmutables {
                      /// @notice The contract that deployed the pool, which must adhere to the IUniswapV3Factory interface
                      /// @return The contract address
                      function factory() external view returns (address);
                      /// @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);
                      /// @notice The pool tick spacing
                      /// @dev Ticks can only be used at multiples of this value, minimum of 1 and always positive
                      /// e.g.: a tickSpacing of 3 means ticks can be initialized every 3rd tick, i.e., ..., -6, -3, 0, 3, 6, ...
                      /// This value is an int24 to avoid casting even though it is always positive.
                      /// @return The tick spacing
                      function tickSpacing() external view returns (int24);
                      /// @notice The maximum amount of position liquidity that can use any tick in the range
                      /// @dev This parameter is enforced per tick to prevent liquidity from overflowing a uint128 at any point, and
                      /// also prevents out-of-range liquidity from being used to prevent adding in-range liquidity to a pool
                      /// @return The max amount of liquidity per tick
                      function maxLiquidityPerTick() external view returns (uint128);
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.5.0;
                  /// @title Pool state that can change
                  /// @notice These methods compose the pool's state, and can change with any frequency including multiple times
                  /// per transaction
                  interface IUniswapV3PoolState {
                      /// @notice The 0th storage slot in the pool stores many values, and is exposed as a single method to save gas
                      /// when accessed externally.
                      /// @return sqrtPriceX96 The current price of the pool as a sqrt(token1/token0) Q64.96 value
                      /// tick The current tick of the pool, i.e. according to the last tick transition that was run.
                      /// This value may not always be equal to SqrtTickMath.getTickAtSqrtRatio(sqrtPriceX96) if the price is on a tick
                      /// boundary.
                      /// observationIndex The index of the last oracle observation that was written,
                      /// observationCardinality The current maximum number of observations stored in the pool,
                      /// observationCardinalityNext The next maximum number of observations, to be updated when the observation.
                      /// feeProtocol The protocol fee for both tokens of the pool.
                      /// Encoded as two 4 bit values, where the protocol fee of token1 is shifted 4 bits and the protocol fee of token0
                      /// is the lower 4 bits. Used as the denominator of a fraction of the swap fee, e.g. 4 means 1/4th of the swap fee.
                      /// unlocked Whether the pool is currently locked to reentrancy
                      function slot0()
                          external
                          view
                          returns (
                              uint160 sqrtPriceX96,
                              int24 tick,
                              uint16 observationIndex,
                              uint16 observationCardinality,
                              uint16 observationCardinalityNext,
                              uint8 feeProtocol,
                              bool unlocked
                          );
                      /// @notice The fee growth as a Q128.128 fees of token0 collected per unit of liquidity for the entire life of the pool
                      /// @dev This value can overflow the uint256
                      function feeGrowthGlobal0X128() external view returns (uint256);
                      /// @notice The fee growth as a Q128.128 fees of token1 collected per unit of liquidity for the entire life of the pool
                      /// @dev This value can overflow the uint256
                      function feeGrowthGlobal1X128() external view returns (uint256);
                      /// @notice The amounts of token0 and token1 that are owed to the protocol
                      /// @dev Protocol fees will never exceed uint128 max in either token
                      function protocolFees() external view returns (uint128 token0, uint128 token1);
                      /// @notice The currently in range liquidity available to the pool
                      /// @dev This value has no relationship to the total liquidity across all ticks
                      function liquidity() external view returns (uint128);
                      /// @notice Look up information about a specific tick in the pool
                      /// @param tick The tick to look up
                      /// @return liquidityGross the total amount of position liquidity that uses the pool either as tick lower or
                      /// tick upper,
                      /// liquidityNet how much liquidity changes when the pool price crosses the tick,
                      /// feeGrowthOutside0X128 the fee growth on the other side of the tick from the current tick in token0,
                      /// feeGrowthOutside1X128 the fee growth on the other side of the tick from the current tick in token1,
                      /// tickCumulativeOutside the cumulative tick value on the other side of the tick from the current tick
                      /// secondsPerLiquidityOutsideX128 the seconds spent per liquidity on the other side of the tick from the current tick,
                      /// secondsOutside the seconds spent on the other side of the tick from the current tick,
                      /// initialized Set to true if the tick is initialized, i.e. liquidityGross is greater than 0, otherwise equal to false.
                      /// Outside values can only be used if the tick is initialized, i.e. if liquidityGross is greater than 0.
                      /// In addition, these values are only relative and must be used only in comparison to previous snapshots for
                      /// a specific position.
                      function ticks(int24 tick)
                          external
                          view
                          returns (
                              uint128 liquidityGross,
                              int128 liquidityNet,
                              uint256 feeGrowthOutside0X128,
                              uint256 feeGrowthOutside1X128,
                              int56 tickCumulativeOutside,
                              uint160 secondsPerLiquidityOutsideX128,
                              uint32 secondsOutside,
                              bool initialized
                          );
                      /// @notice Returns 256 packed tick initialized boolean values. See TickBitmap for more information
                      function tickBitmap(int16 wordPosition) external view returns (uint256);
                      /// @notice Returns the information about a position by the position's key
                      /// @param key The position's key is a hash of a preimage composed by the owner, tickLower and tickUpper
                      /// @return _liquidity The amount of liquidity in the position,
                      /// Returns feeGrowthInside0LastX128 fee growth of token0 inside the tick range as of the last mint/burn/poke,
                      /// Returns feeGrowthInside1LastX128 fee growth of token1 inside the tick range as of the last mint/burn/poke,
                      /// Returns tokensOwed0 the computed amount of token0 owed to the position as of the last mint/burn/poke,
                      /// Returns tokensOwed1 the computed amount of token1 owed to the position as of the last mint/burn/poke
                      function positions(bytes32 key)
                          external
                          view
                          returns (
                              uint128 _liquidity,
                              uint256 feeGrowthInside0LastX128,
                              uint256 feeGrowthInside1LastX128,
                              uint128 tokensOwed0,
                              uint128 tokensOwed1
                          );
                      /// @notice Returns data about a specific observation index
                      /// @param index The element of the observations array to fetch
                      /// @dev You most likely want to use #observe() instead of this method to get an observation as of some amount of time
                      /// ago, rather than at a specific index in the array.
                      /// @return blockTimestamp The timestamp of the observation,
                      /// Returns tickCumulative the tick multiplied by seconds elapsed for the life of the pool as of the observation timestamp,
                      /// Returns secondsPerLiquidityCumulativeX128 the seconds per in range liquidity for the life of the pool as of the observation timestamp,
                      /// Returns initialized whether the observation has been initialized and the values are safe to use
                      function observations(uint256 index)
                          external
                          view
                          returns (
                              uint32 blockTimestamp,
                              int56 tickCumulative,
                              uint160 secondsPerLiquidityCumulativeX128,
                              bool initialized
                          );
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.5.0;
                  /// @title Pool state that is not stored
                  /// @notice Contains view functions to provide information about the pool that is computed rather than stored on the
                  /// blockchain. The functions here may have variable gas costs.
                  interface IUniswapV3PoolDerivedState {
                      /// @notice Returns the cumulative tick and liquidity as of each timestamp `secondsAgo` from the current block timestamp
                      /// @dev To get a time weighted average tick or liquidity-in-range, you must call this with two values, one representing
                      /// the beginning of the period and another for the end of the period. E.g., to get the last hour time-weighted average tick,
                      /// you must call it with secondsAgos = [3600, 0].
                      /// @dev The time weighted average tick represents the geometric time weighted average price of the pool, in
                      /// log base sqrt(1.0001) of token1 / token0. The TickMath library can be used to go from a tick value to a ratio.
                      /// @param secondsAgos From how long ago each cumulative tick and liquidity value should be returned
                      /// @return tickCumulatives Cumulative tick values as of each `secondsAgos` from the current block timestamp
                      /// @return secondsPerLiquidityCumulativeX128s Cumulative seconds per liquidity-in-range value as of each `secondsAgos` from the current block
                      /// timestamp
                      function observe(uint32[] calldata secondsAgos)
                          external
                          view
                          returns (int56[] memory tickCumulatives, uint160[] memory secondsPerLiquidityCumulativeX128s);
                      /// @notice Returns a snapshot of the tick cumulative, seconds per liquidity and seconds inside a tick range
                      /// @dev Snapshots must only be compared to other snapshots, taken over a period for which a position existed.
                      /// I.e., snapshots cannot be compared if a position is not held for the entire period between when the first
                      /// snapshot is taken and the second snapshot is taken.
                      /// @param tickLower The lower tick of the range
                      /// @param tickUpper The upper tick of the range
                      /// @return tickCumulativeInside The snapshot of the tick accumulator for the range
                      /// @return secondsPerLiquidityInsideX128 The snapshot of seconds per liquidity for the range
                      /// @return secondsInside The snapshot of seconds per liquidity for the range
                      function snapshotCumulativesInside(int24 tickLower, int24 tickUpper)
                          external
                          view
                          returns (
                              int56 tickCumulativeInside,
                              uint160 secondsPerLiquidityInsideX128,
                              uint32 secondsInside
                          );
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.5.0;
                  /// @title Permissionless pool actions
                  /// @notice Contains pool methods that can be called by anyone
                  interface IUniswapV3PoolActions {
                      /// @notice Sets the initial price for the pool
                      /// @dev Price is represented as a sqrt(amountToken1/amountToken0) Q64.96 value
                      /// @param sqrtPriceX96 the initial sqrt price of the pool as a Q64.96
                      function initialize(uint160 sqrtPriceX96) external;
                      /// @notice Adds liquidity for the given recipient/tickLower/tickUpper position
                      /// @dev The caller of this method receives a callback in the form of IUniswapV3MintCallback#uniswapV3MintCallback
                      /// in which they must pay any token0 or token1 owed for the liquidity. The amount of token0/token1 due depends
                      /// on tickLower, tickUpper, the amount of liquidity, and the current price.
                      /// @param recipient The address for which the liquidity will be created
                      /// @param tickLower The lower tick of the position in which to add liquidity
                      /// @param tickUpper The upper tick of the position in which to add liquidity
                      /// @param amount The amount of liquidity to mint
                      /// @param data Any data that should be passed through to the callback
                      /// @return amount0 The amount of token0 that was paid to mint the given amount of liquidity. Matches the value in the callback
                      /// @return amount1 The amount of token1 that was paid to mint the given amount of liquidity. Matches the value in the callback
                      function mint(
                          address recipient,
                          int24 tickLower,
                          int24 tickUpper,
                          uint128 amount,
                          bytes calldata data
                      ) external returns (uint256 amount0, uint256 amount1);
                      /// @notice Collects tokens owed to a position
                      /// @dev Does not recompute fees earned, which must be done either via mint or burn of any amount of liquidity.
                      /// Collect must be called by the position owner. To withdraw only token0 or only token1, amount0Requested or
                      /// amount1Requested may be set to zero. To withdraw all tokens owed, caller may pass any value greater than the
                      /// actual tokens owed, e.g. type(uint128).max. Tokens owed may be from accumulated swap fees or burned liquidity.
                      /// @param recipient The address which should receive the fees collected
                      /// @param tickLower The lower tick of the position for which to collect fees
                      /// @param tickUpper The upper tick of the position for which to collect fees
                      /// @param amount0Requested How much token0 should be withdrawn from the fees owed
                      /// @param amount1Requested How much token1 should be withdrawn from the fees owed
                      /// @return amount0 The amount of fees collected in token0
                      /// @return amount1 The amount of fees collected in token1
                      function collect(
                          address recipient,
                          int24 tickLower,
                          int24 tickUpper,
                          uint128 amount0Requested,
                          uint128 amount1Requested
                      ) external returns (uint128 amount0, uint128 amount1);
                      /// @notice Burn liquidity from the sender and account tokens owed for the liquidity to the position
                      /// @dev Can be used to trigger a recalculation of fees owed to a position by calling with an amount of 0
                      /// @dev Fees must be collected separately via a call to #collect
                      /// @param tickLower The lower tick of the position for which to burn liquidity
                      /// @param tickUpper The upper tick of the position for which to burn liquidity
                      /// @param amount How much liquidity to burn
                      /// @return amount0 The amount of token0 sent to the recipient
                      /// @return amount1 The amount of token1 sent to the recipient
                      function burn(
                          int24 tickLower,
                          int24 tickUpper,
                          uint128 amount
                      ) external returns (uint256 amount0, uint256 amount1);
                      /// @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 Receive token0 and/or token1 and pay it back, plus a fee, in the callback
                      /// @dev The caller of this method receives a callback in the form of IUniswapV3FlashCallback#uniswapV3FlashCallback
                      /// @dev Can be used to donate underlying tokens pro-rata to currently in-range liquidity providers by calling
                      /// with 0 amount{0,1} and sending the donation amount(s) from the callback
                      /// @param recipient The address which will receive the token0 and token1 amounts
                      /// @param amount0 The amount of token0 to send
                      /// @param amount1 The amount of token1 to send
                      /// @param data Any data to be passed through to the callback
                      function flash(
                          address recipient,
                          uint256 amount0,
                          uint256 amount1,
                          bytes calldata data
                      ) external;
                      /// @notice Increase the maximum number of price and liquidity observations that this pool will store
                      /// @dev This method is no-op if the pool already has an observationCardinalityNext greater than or equal to
                      /// the input observationCardinalityNext.
                      /// @param observationCardinalityNext The desired minimum number of observations for the pool to store
                      function increaseObservationCardinalityNext(uint16 observationCardinalityNext) external;
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.5.0;
                  /// @title Permissioned pool actions
                  /// @notice Contains pool methods that may only be called by the factory owner
                  interface IUniswapV3PoolOwnerActions {
                      /// @notice Set the denominator of the protocol's % share of the fees
                      /// @param feeProtocol0 new protocol fee for token0 of the pool
                      /// @param feeProtocol1 new protocol fee for token1 of the pool
                      function setFeeProtocol(uint8 feeProtocol0, uint8 feeProtocol1) external;
                      /// @notice Collect the protocol fee accrued to the pool
                      /// @param recipient The address to which collected protocol fees should be sent
                      /// @param amount0Requested The maximum amount of token0 to send, can be 0 to collect fees in only token1
                      /// @param amount1Requested The maximum amount of token1 to send, can be 0 to collect fees in only token0
                      /// @return amount0 The protocol fee collected in token0
                      /// @return amount1 The protocol fee collected in token1
                      function collectProtocol(
                          address recipient,
                          uint128 amount0Requested,
                          uint128 amount1Requested
                      ) external returns (uint128 amount0, uint128 amount1);
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.5.0;
                  /// @title Events emitted by a pool
                  /// @notice Contains all events emitted by the pool
                  interface IUniswapV3PoolEvents {
                      /// @notice Emitted exactly once by a pool when #initialize is first called on the pool
                      /// @dev Mint/Burn/Swap cannot be emitted by the pool before Initialize
                      /// @param sqrtPriceX96 The initial sqrt price of the pool, as a Q64.96
                      /// @param tick The initial tick of the pool, i.e. log base 1.0001 of the starting price of the pool
                      event Initialize(uint160 sqrtPriceX96, int24 tick);
                      /// @notice Emitted when liquidity is minted for a given position
                      /// @param sender The address that minted the liquidity
                      /// @param owner The owner of the position and recipient of any minted liquidity
                      /// @param tickLower The lower tick of the position
                      /// @param tickUpper The upper tick of the position
                      /// @param amount The amount of liquidity minted to the position range
                      /// @param amount0 How much token0 was required for the minted liquidity
                      /// @param amount1 How much token1 was required for the minted liquidity
                      event Mint(
                          address sender,
                          address indexed owner,
                          int24 indexed tickLower,
                          int24 indexed tickUpper,
                          uint128 amount,
                          uint256 amount0,
                          uint256 amount1
                      );
                      /// @notice Emitted when fees are collected by the owner of a position
                      /// @dev Collect events may be emitted with zero amount0 and amount1 when the caller chooses not to collect fees
                      /// @param owner The owner of the position for which fees are collected
                      /// @param tickLower The lower tick of the position
                      /// @param tickUpper The upper tick of the position
                      /// @param amount0 The amount of token0 fees collected
                      /// @param amount1 The amount of token1 fees collected
                      event Collect(
                          address indexed owner,
                          address recipient,
                          int24 indexed tickLower,
                          int24 indexed tickUpper,
                          uint128 amount0,
                          uint128 amount1
                      );
                      /// @notice Emitted when a position's liquidity is removed
                      /// @dev Does not withdraw any fees earned by the liquidity position, which must be withdrawn via #collect
                      /// @param owner The owner of the position for which liquidity is removed
                      /// @param tickLower The lower tick of the position
                      /// @param tickUpper The upper tick of the position
                      /// @param amount The amount of liquidity to remove
                      /// @param amount0 The amount of token0 withdrawn
                      /// @param amount1 The amount of token1 withdrawn
                      event Burn(
                          address indexed owner,
                          int24 indexed tickLower,
                          int24 indexed tickUpper,
                          uint128 amount,
                          uint256 amount0,
                          uint256 amount1
                      );
                      /// @notice Emitted by the pool for any swaps between token0 and token1
                      /// @param sender The address that initiated the swap call, and that received the callback
                      /// @param recipient The address that received the output of the swap
                      /// @param amount0 The delta of the token0 balance of the pool
                      /// @param amount1 The delta of the token1 balance of the pool
                      /// @param sqrtPriceX96 The sqrt(price) of the pool after the swap, as a Q64.96
                      /// @param liquidity The liquidity of the pool after the swap
                      /// @param tick The log base 1.0001 of price of the pool after the swap
                      event Swap(
                          address indexed sender,
                          address indexed recipient,
                          int256 amount0,
                          int256 amount1,
                          uint160 sqrtPriceX96,
                          uint128 liquidity,
                          int24 tick
                      );
                      /// @notice Emitted by the pool for any flashes of token0/token1
                      /// @param sender The address that initiated the swap call, and that received the callback
                      /// @param recipient The address that received the tokens from flash
                      /// @param amount0 The amount of token0 that was flashed
                      /// @param amount1 The amount of token1 that was flashed
                      /// @param paid0 The amount of token0 paid for the flash, which can exceed the amount0 plus the fee
                      /// @param paid1 The amount of token1 paid for the flash, which can exceed the amount1 plus the fee
                      event Flash(
                          address indexed sender,
                          address indexed recipient,
                          uint256 amount0,
                          uint256 amount1,
                          uint256 paid0,
                          uint256 paid1
                      );
                      /// @notice Emitted by the pool for increases to the number of observations that can be stored
                      /// @dev observationCardinalityNext is not the observation cardinality until an observation is written at the index
                      /// just before a mint/swap/burn.
                      /// @param observationCardinalityNextOld The previous value of the next observation cardinality
                      /// @param observationCardinalityNextNew The updated value of the next observation cardinality
                      event IncreaseObservationCardinalityNext(
                          uint16 observationCardinalityNextOld,
                          uint16 observationCardinalityNextNew
                      );
                      /// @notice Emitted when the protocol fee is changed by the pool
                      /// @param feeProtocol0Old The previous value of the token0 protocol fee
                      /// @param feeProtocol1Old The previous value of the token1 protocol fee
                      /// @param feeProtocol0New The updated value of the token0 protocol fee
                      /// @param feeProtocol1New The updated value of the token1 protocol fee
                      event SetFeeProtocol(uint8 feeProtocol0Old, uint8 feeProtocol1Old, uint8 feeProtocol0New, uint8 feeProtocol1New);
                      /// @notice Emitted when the collected protocol fees are withdrawn by the factory owner
                      /// @param sender The address that collects the protocol fees
                      /// @param recipient The address that receives the collected protocol fees
                      /// @param amount0 The amount of token0 protocol fees that is withdrawn
                      /// @param amount0 The amount of token1 protocol fees that is withdrawn
                      event CollectProtocol(address indexed sender, address indexed recipient, uint128 amount0, uint128 amount1);
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  /*
                   * @title Solidity Bytes Arrays Utils
                   * @author Gonçalo Sá <[email protected]>
                   *
                   * @dev Bytes tightly packed arrays utility library for ethereum contracts written in Solidity.
                   *      The library lets you concatenate, slice and type cast bytes arrays both in memory and storage.
                   */
                  pragma solidity >=0.5.0 <0.8.0;
                  library BytesLib {
                      function slice(
                          bytes memory _bytes,
                          uint256 _start,
                          uint256 _length
                      ) internal pure returns (bytes memory) {
                          require(_length + 31 >= _length, 'slice_overflow');
                          require(_start + _length >= _start, 'slice_overflow');
                          require(_bytes.length >= _start + _length, 'slice_outOfBounds');
                          bytes memory tempBytes;
                          assembly {
                              switch iszero(_length)
                                  case 0 {
                                      // Get a location of some free memory and store it in tempBytes as
                                      // Solidity does for memory variables.
                                      tempBytes := mload(0x40)
                                      // The first word of the slice result is potentially a partial
                                      // word read from the original array. To read it, we calculate
                                      // the length of that partial word and start copying that many
                                      // bytes into the array. The first word we copy will start with
                                      // data we don't care about, but the last `lengthmod` bytes will
                                      // land at the beginning of the contents of the new array. When
                                      // we're done copying, we overwrite the full first word with
                                      // the actual length of the slice.
                                      let lengthmod := and(_length, 31)
                                      // The multiplication in the next line is necessary
                                      // because when slicing multiples of 32 bytes (lengthmod == 0)
                                      // the following copy loop was copying the origin's length
                                      // and then ending prematurely not copying everything it should.
                                      let mc := add(add(tempBytes, lengthmod), mul(0x20, iszero(lengthmod)))
                                      let end := add(mc, _length)
                                      for {
                                          // The multiplication in the next line has the same exact purpose
                                          // as the one above.
                                          let cc := add(add(add(_bytes, lengthmod), mul(0x20, iszero(lengthmod))), _start)
                                      } lt(mc, end) {
                                          mc := add(mc, 0x20)
                                          cc := add(cc, 0x20)
                                      } {
                                          mstore(mc, mload(cc))
                                      }
                                      mstore(tempBytes, _length)
                                      //update free-memory pointer
                                      //allocating the array padded to 32 bytes like the compiler does now
                                      mstore(0x40, and(add(mc, 31), not(31)))
                                  }
                                  //if we want a zero-length slice let's just return a zero-length array
                                  default {
                                      tempBytes := mload(0x40)
                                      //zero out the 32 bytes slice we are about to return
                                      //we need to do it because Solidity does not garbage collect
                                      mstore(tempBytes, 0)
                                      mstore(0x40, add(tempBytes, 0x20))
                                  }
                          }
                          return tempBytes;
                      }
                      function toAddress(bytes memory _bytes, uint256 _start) internal pure returns (address) {
                          require(_start + 20 >= _start, 'toAddress_overflow');
                          require(_bytes.length >= _start + 20, 'toAddress_outOfBounds');
                          address tempAddress;
                          assembly {
                              tempAddress := div(mload(add(add(_bytes, 0x20), _start)), 0x1000000000000000000000000)
                          }
                          return tempAddress;
                      }
                      function toUint24(bytes memory _bytes, uint256 _start) internal pure returns (uint24) {
                          require(_start + 3 >= _start, 'toUint24_overflow');
                          require(_bytes.length >= _start + 3, 'toUint24_outOfBounds');
                          uint24 tempUint;
                          assembly {
                              tempUint := mload(add(add(_bytes, 0x3), _start))
                          }
                          return tempUint;
                      }
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.7.5;
                  pragma abicoder v2;
                  /// @title OracleSlippage interface
                  /// @notice Enables slippage checks against oracle prices
                  interface IOracleSlippage {
                      /// @notice Ensures that the current (synthetic) tick over the path is no worse than
                      /// `maximumTickDivergence` ticks away from the average as of `secondsAgo`
                      /// @param path The path to fetch prices over
                      /// @param maximumTickDivergence The maximum number of ticks that the price can degrade by
                      /// @param secondsAgo The number of seconds ago to compute oracle prices against
                      function checkOracleSlippage(
                          bytes memory path,
                          uint24 maximumTickDivergence,
                          uint32 secondsAgo
                      ) external view;
                      /// @notice Ensures that the weighted average current (synthetic) tick over the path is no
                      /// worse than `maximumTickDivergence` ticks away from the average as of `secondsAgo`
                      /// @param paths The paths to fetch prices over
                      /// @param amounts The weights for each entry in `paths`
                      /// @param maximumTickDivergence The maximum number of ticks that the price can degrade by
                      /// @param secondsAgo The number of seconds ago to compute oracle prices against
                      function checkOracleSlippage(
                          bytes[] memory paths,
                          uint128[] memory amounts,
                          uint24 maximumTickDivergence,
                          uint32 secondsAgo
                      ) external view;
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity =0.7.6;
                  /// @title Function for getting block timestamp
                  /// @dev Base contract that is overridden for tests
                  abstract contract BlockTimestamp {
                      /// @dev Method that exists purely to be overridden for tests
                      /// @return The current block timestamp
                      function _blockTimestamp() internal view virtual returns (uint256) {
                          return block.timestamp;
                      }
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.5.0 <0.8.0;
                  import '@uniswap/v3-core/contracts/libraries/FullMath.sol';
                  import '@uniswap/v3-core/contracts/libraries/TickMath.sol';
                  import '@uniswap/v3-core/contracts/interfaces/IUniswapV3Pool.sol';
                  /// @title Oracle library
                  /// @notice Provides functions to integrate with V3 pool oracle
                  library OracleLibrary {
                      /// @notice Calculates time-weighted means of tick and liquidity for a given Uniswap V3 pool
                      /// @param pool Address of the pool that we want to observe
                      /// @param secondsAgo Number of seconds in the past from which to calculate the time-weighted means
                      /// @return arithmeticMeanTick The arithmetic mean tick from (block.timestamp - secondsAgo) to block.timestamp
                      /// @return harmonicMeanLiquidity The harmonic mean liquidity from (block.timestamp - secondsAgo) to block.timestamp
                      function consult(address pool, uint32 secondsAgo)
                          internal
                          view
                          returns (int24 arithmeticMeanTick, uint128 harmonicMeanLiquidity)
                      {
                          require(secondsAgo != 0, 'BP');
                          uint32[] memory secondsAgos = new uint32[](2);
                          secondsAgos[0] = secondsAgo;
                          secondsAgos[1] = 0;
                          (int56[] memory tickCumulatives, uint160[] memory secondsPerLiquidityCumulativeX128s) =
                              IUniswapV3Pool(pool).observe(secondsAgos);
                          int56 tickCumulativesDelta = tickCumulatives[1] - tickCumulatives[0];
                          uint160 secondsPerLiquidityCumulativesDelta =
                              secondsPerLiquidityCumulativeX128s[1] - secondsPerLiquidityCumulativeX128s[0];
                          arithmeticMeanTick = int24(tickCumulativesDelta / secondsAgo);
                          // Always round to negative infinity
                          if (tickCumulativesDelta < 0 && (tickCumulativesDelta % secondsAgo != 0)) arithmeticMeanTick--;
                          // We are multiplying here instead of shifting to ensure that harmonicMeanLiquidity doesn't overflow uint128
                          uint192 secondsAgoX160 = uint192(secondsAgo) * type(uint160).max;
                          harmonicMeanLiquidity = uint128(secondsAgoX160 / (uint192(secondsPerLiquidityCumulativesDelta) << 32));
                      }
                      /// @notice Given a tick and a token amount, calculates the amount of token received in exchange
                      /// @param tick Tick value used to calculate the quote
                      /// @param baseAmount Amount of token to be converted
                      /// @param baseToken Address of an ERC20 token contract used as the baseAmount denomination
                      /// @param quoteToken Address of an ERC20 token contract used as the quoteAmount denomination
                      /// @return quoteAmount Amount of quoteToken received for baseAmount of baseToken
                      function getQuoteAtTick(
                          int24 tick,
                          uint128 baseAmount,
                          address baseToken,
                          address quoteToken
                      ) internal pure returns (uint256 quoteAmount) {
                          uint160 sqrtRatioX96 = TickMath.getSqrtRatioAtTick(tick);
                          // Calculate quoteAmount with better precision if it doesn't overflow when multiplied by itself
                          if (sqrtRatioX96 <= type(uint128).max) {
                              uint256 ratioX192 = uint256(sqrtRatioX96) * sqrtRatioX96;
                              quoteAmount = baseToken < quoteToken
                                  ? FullMath.mulDiv(ratioX192, baseAmount, 1 << 192)
                                  : FullMath.mulDiv(1 << 192, baseAmount, ratioX192);
                          } else {
                              uint256 ratioX128 = FullMath.mulDiv(sqrtRatioX96, sqrtRatioX96, 1 << 64);
                              quoteAmount = baseToken < quoteToken
                                  ? FullMath.mulDiv(ratioX128, baseAmount, 1 << 128)
                                  : FullMath.mulDiv(1 << 128, baseAmount, ratioX128);
                          }
                      }
                      /// @notice Given a pool, it returns the number of seconds ago of the oldest stored observation
                      /// @param pool Address of Uniswap V3 pool that we want to observe
                      /// @return secondsAgo The number of seconds ago of the oldest observation stored for the pool
                      function getOldestObservationSecondsAgo(address pool) internal view returns (uint32 secondsAgo) {
                          (, , uint16 observationIndex, uint16 observationCardinality, , , ) = IUniswapV3Pool(pool).slot0();
                          require(observationCardinality > 0, 'NI');
                          (uint32 observationTimestamp, , , bool initialized) =
                              IUniswapV3Pool(pool).observations((observationIndex + 1) % observationCardinality);
                          // The next index might not be initialized if the cardinality is in the process of increasing
                          // In this case the oldest observation is always in index 0
                          if (!initialized) {
                              (observationTimestamp, , , ) = IUniswapV3Pool(pool).observations(0);
                          }
                          secondsAgo = uint32(block.timestamp) - observationTimestamp;
                      }
                      /// @notice Given a pool, it returns the tick value as of the start of the current block
                      /// @param pool Address of Uniswap V3 pool
                      /// @return The tick that the pool was in at the start of the current block
                      function getBlockStartingTickAndLiquidity(address pool) internal view returns (int24, uint128) {
                          (, int24 tick, uint16 observationIndex, uint16 observationCardinality, , , ) = IUniswapV3Pool(pool).slot0();
                          // 2 observations are needed to reliably calculate the block starting tick
                          require(observationCardinality > 1, 'NEO');
                          // If the latest observation occurred in the past, then no tick-changing trades have happened in this block
                          // therefore the tick in `slot0` is the same as at the beginning of the current block.
                          // We don't need to check if this observation is initialized - it is guaranteed to be.
                          (uint32 observationTimestamp, int56 tickCumulative, uint160 secondsPerLiquidityCumulativeX128, ) =
                              IUniswapV3Pool(pool).observations(observationIndex);
                          if (observationTimestamp != uint32(block.timestamp)) {
                              return (tick, IUniswapV3Pool(pool).liquidity());
                          }
                          uint256 prevIndex = (uint256(observationIndex) + observationCardinality - 1) % observationCardinality;
                          (
                              uint32 prevObservationTimestamp,
                              int56 prevTickCumulative,
                              uint160 prevSecondsPerLiquidityCumulativeX128,
                              bool prevInitialized
                          ) = IUniswapV3Pool(pool).observations(prevIndex);
                          require(prevInitialized, 'ONI');
                          uint32 delta = observationTimestamp - prevObservationTimestamp;
                          tick = int24((tickCumulative - prevTickCumulative) / delta);
                          uint128 liquidity =
                              uint128(
                                  (uint192(delta) * type(uint160).max) /
                                      (uint192(secondsPerLiquidityCumulativeX128 - prevSecondsPerLiquidityCumulativeX128) << 32)
                              );
                          return (tick, liquidity);
                      }
                      /// @notice Information for calculating a weighted arithmetic mean tick
                      struct WeightedTickData {
                          int24 tick;
                          uint128 weight;
                      }
                      /// @notice Given an array of ticks and weights, calculates the weighted arithmetic mean tick
                      /// @param weightedTickData An array of ticks and weights
                      /// @return weightedArithmeticMeanTick The weighted arithmetic mean tick
                      /// @dev Each entry of `weightedTickData` should represents ticks from pools with the same underlying pool tokens. If they do not,
                      /// extreme care must be taken to ensure that ticks are comparable (including decimal differences).
                      /// @dev Note that the weighted arithmetic mean tick corresponds to the weighted geometric mean price.
                      function getWeightedArithmeticMeanTick(WeightedTickData[] memory weightedTickData)
                          internal
                          pure
                          returns (int24 weightedArithmeticMeanTick)
                      {
                          // Accumulates the sum of products between each tick and its weight
                          int256 numerator;
                          // Accumulates the sum of the weights
                          uint256 denominator;
                          // Products fit in 152 bits, so it would take an array of length ~2**104 to overflow this logic
                          for (uint256 i; i < weightedTickData.length; i++) {
                              numerator += weightedTickData[i].tick * int256(weightedTickData[i].weight);
                              denominator += weightedTickData[i].weight;
                          }
                          weightedArithmeticMeanTick = int24(numerator / int256(denominator));
                          // Always round to negative infinity
                          if (numerator < 0 && (numerator % int256(denominator) != 0)) weightedArithmeticMeanTick--;
                      }
                  }
                  // SPDX-License-Identifier: MIT
                  pragma solidity >=0.4.0;
                  /// @title Contains 512-bit math functions
                  /// @notice Facilitates multiplication and division that can have overflow of an intermediate value without any loss of precision
                  /// @dev Handles "phantom overflow" i.e., allows multiplication and division where an intermediate value overflows 256 bits
                  library FullMath {
                      /// @notice Calculates floor(a×b÷denominator) with full precision. Throws if result overflows a uint256 or denominator == 0
                      /// @param a The multiplicand
                      /// @param b The multiplier
                      /// @param denominator The divisor
                      /// @return result The 256-bit result
                      /// @dev Credit to Remco Bloemen under MIT license https://xn--2-umb.com/21/muldiv
                      function mulDiv(
                          uint256 a,
                          uint256 b,
                          uint256 denominator
                      ) internal pure returns (uint256 result) {
                          // 512-bit multiply [prod1 prod0] = a * b
                          // Compute the product mod 2**256 and mod 2**256 - 1
                          // then use the Chinese Remainder Theorem to reconstruct
                          // the 512 bit result. The result is stored in two 256
                          // variables such that product = prod1 * 2**256 + prod0
                          uint256 prod0; // Least significant 256 bits of the product
                          uint256 prod1; // Most significant 256 bits of the product
                          assembly {
                              let mm := mulmod(a, b, not(0))
                              prod0 := mul(a, b)
                              prod1 := sub(sub(mm, prod0), lt(mm, prod0))
                          }
                          // Handle non-overflow cases, 256 by 256 division
                          if (prod1 == 0) {
                              require(denominator > 0);
                              assembly {
                                  result := div(prod0, denominator)
                              }
                              return result;
                          }
                          // Make sure the result is less than 2**256.
                          // Also prevents denominator == 0
                          require(denominator > prod1);
                          ///////////////////////////////////////////////
                          // 512 by 256 division.
                          ///////////////////////////////////////////////
                          // Make division exact by subtracting the remainder from [prod1 prod0]
                          // Compute remainder using mulmod
                          uint256 remainder;
                          assembly {
                              remainder := mulmod(a, b, denominator)
                          }
                          // Subtract 256 bit number from 512 bit number
                          assembly {
                              prod1 := sub(prod1, gt(remainder, prod0))
                              prod0 := sub(prod0, remainder)
                          }
                          // Factor powers of two out of denominator
                          // Compute largest power of two divisor of denominator.
                          // Always >= 1.
                          uint256 twos = -denominator & denominator;
                          // Divide denominator by power of two
                          assembly {
                              denominator := div(denominator, twos)
                          }
                          // Divide [prod1 prod0] by the factors of two
                          assembly {
                              prod0 := div(prod0, twos)
                          }
                          // Shift in bits from prod1 into prod0. For this we need
                          // to flip `twos` such that it is 2**256 / twos.
                          // If twos is zero, then it becomes one
                          assembly {
                              twos := add(div(sub(0, twos), twos), 1)
                          }
                          prod0 |= prod1 * twos;
                          // Invert denominator mod 2**256
                          // Now that denominator is an odd number, it has an inverse
                          // modulo 2**256 such that denominator * inv = 1 mod 2**256.
                          // Compute the inverse by starting with a seed that is correct
                          // correct for four bits. That is, denominator * inv = 1 mod 2**4
                          uint256 inv = (3 * denominator) ^ 2;
                          // Now use Newton-Raphson iteration to improve the precision.
                          // Thanks to Hensel's lifting lemma, this also works in modular
                          // arithmetic, doubling the correct bits in each step.
                          inv *= 2 - denominator * inv; // inverse mod 2**8
                          inv *= 2 - denominator * inv; // inverse mod 2**16
                          inv *= 2 - denominator * inv; // inverse mod 2**32
                          inv *= 2 - denominator * inv; // inverse mod 2**64
                          inv *= 2 - denominator * inv; // inverse mod 2**128
                          inv *= 2 - denominator * inv; // inverse mod 2**256
                          // Because the division is now exact we can divide by multiplying
                          // with the modular inverse of denominator. This will give us the
                          // correct result modulo 2**256. Since the precoditions guarantee
                          // that the outcome is less than 2**256, this is the final result.
                          // We don't need to compute the high bits of the result and prod1
                          // is no longer required.
                          result = prod0 * inv;
                          return result;
                      }
                      /// @notice Calculates ceil(a×b÷denominator) with full precision. Throws if result overflows a uint256 or denominator == 0
                      /// @param a The multiplicand
                      /// @param b The multiplier
                      /// @param denominator The divisor
                      /// @return result The 256-bit result
                      function mulDivRoundingUp(
                          uint256 a,
                          uint256 b,
                          uint256 denominator
                      ) internal pure returns (uint256 result) {
                          result = mulDiv(a, b, denominator);
                          if (mulmod(a, b, denominator) > 0) {
                              require(result < type(uint256).max);
                              result++;
                          }
                      }
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.7.5;
                  pragma abicoder v2;
                  import '@openzeppelin/contracts/token/ERC721/IERC721Metadata.sol';
                  import '@openzeppelin/contracts/token/ERC721/IERC721Enumerable.sol';
                  import './IPoolInitializer.sol';
                  import './IERC721Permit.sol';
                  import './IPeripheryPayments.sol';
                  import './IPeripheryImmutableState.sol';
                  import '../libraries/PoolAddress.sol';
                  /// @title Non-fungible token for positions
                  /// @notice Wraps Uniswap V3 positions in a non-fungible token interface which allows for them to be transferred
                  /// and authorized.
                  interface INonfungiblePositionManager is
                      IPoolInitializer,
                      IPeripheryPayments,
                      IPeripheryImmutableState,
                      IERC721Metadata,
                      IERC721Enumerable,
                      IERC721Permit
                  {
                      /// @notice Emitted when liquidity is increased for a position NFT
                      /// @dev Also emitted when a token is minted
                      /// @param tokenId The ID of the token for which liquidity was increased
                      /// @param liquidity The amount by which liquidity for the NFT position was increased
                      /// @param amount0 The amount of token0 that was paid for the increase in liquidity
                      /// @param amount1 The amount of token1 that was paid for the increase in liquidity
                      event IncreaseLiquidity(uint256 indexed tokenId, uint128 liquidity, uint256 amount0, uint256 amount1);
                      /// @notice Emitted when liquidity is decreased for a position NFT
                      /// @param tokenId The ID of the token for which liquidity was decreased
                      /// @param liquidity The amount by which liquidity for the NFT position was decreased
                      /// @param amount0 The amount of token0 that was accounted for the decrease in liquidity
                      /// @param amount1 The amount of token1 that was accounted for the decrease in liquidity
                      event DecreaseLiquidity(uint256 indexed tokenId, uint128 liquidity, uint256 amount0, uint256 amount1);
                      /// @notice Emitted when tokens are collected for a position NFT
                      /// @dev The amounts reported may not be exactly equivalent to the amounts transferred, due to rounding behavior
                      /// @param tokenId The ID of the token for which underlying tokens were collected
                      /// @param recipient The address of the account that received the collected tokens
                      /// @param amount0 The amount of token0 owed to the position that was collected
                      /// @param amount1 The amount of token1 owed to the position that was collected
                      event Collect(uint256 indexed tokenId, address recipient, uint256 amount0, uint256 amount1);
                      /// @notice Returns the position information associated with a given token ID.
                      /// @dev Throws if the token ID is not valid.
                      /// @param tokenId The ID of the token that represents the position
                      /// @return nonce The nonce for permits
                      /// @return operator The address that is approved for spending
                      /// @return token0 The address of the token0 for a specific pool
                      /// @return token1 The address of the token1 for a specific pool
                      /// @return fee The fee associated with the pool
                      /// @return tickLower The lower end of the tick range for the position
                      /// @return tickUpper The higher end of the tick range for the position
                      /// @return liquidity The liquidity of the position
                      /// @return feeGrowthInside0LastX128 The fee growth of token0 as of the last action on the individual position
                      /// @return feeGrowthInside1LastX128 The fee growth of token1 as of the last action on the individual position
                      /// @return tokensOwed0 The uncollected amount of token0 owed to the position as of the last computation
                      /// @return tokensOwed1 The uncollected amount of token1 owed to the position as of the last computation
                      function positions(uint256 tokenId)
                          external
                          view
                          returns (
                              uint96 nonce,
                              address operator,
                              address token0,
                              address token1,
                              uint24 fee,
                              int24 tickLower,
                              int24 tickUpper,
                              uint128 liquidity,
                              uint256 feeGrowthInside0LastX128,
                              uint256 feeGrowthInside1LastX128,
                              uint128 tokensOwed0,
                              uint128 tokensOwed1
                          );
                      struct MintParams {
                          address token0;
                          address token1;
                          uint24 fee;
                          int24 tickLower;
                          int24 tickUpper;
                          uint256 amount0Desired;
                          uint256 amount1Desired;
                          uint256 amount0Min;
                          uint256 amount1Min;
                          address recipient;
                          uint256 deadline;
                      }
                      /// @notice Creates a new position wrapped in a NFT
                      /// @dev Call this when the pool does exist and is initialized. Note that if the pool is created but not initialized
                      /// a method does not exist, i.e. the pool is assumed to be initialized.
                      /// @param params The params necessary to mint a position, encoded as `MintParams` in calldata
                      /// @return tokenId The ID of the token that represents the minted position
                      /// @return liquidity The amount of liquidity for this position
                      /// @return amount0 The amount of token0
                      /// @return amount1 The amount of token1
                      function mint(MintParams calldata params)
                          external
                          payable
                          returns (
                              uint256 tokenId,
                              uint128 liquidity,
                              uint256 amount0,
                              uint256 amount1
                          );
                      struct IncreaseLiquidityParams {
                          uint256 tokenId;
                          uint256 amount0Desired;
                          uint256 amount1Desired;
                          uint256 amount0Min;
                          uint256 amount1Min;
                          uint256 deadline;
                      }
                      /// @notice Increases the amount of liquidity in a position, with tokens paid by the `msg.sender`
                      /// @param params tokenId The ID of the token for which liquidity is being increased,
                      /// amount0Desired The desired amount of token0 to be spent,
                      /// amount1Desired The desired amount of token1 to be spent,
                      /// amount0Min The minimum amount of token0 to spend, which serves as a slippage check,
                      /// amount1Min The minimum amount of token1 to spend, which serves as a slippage check,
                      /// deadline The time by which the transaction must be included to effect the change
                      /// @return liquidity The new liquidity amount as a result of the increase
                      /// @return amount0 The amount of token0 to acheive resulting liquidity
                      /// @return amount1 The amount of token1 to acheive resulting liquidity
                      function increaseLiquidity(IncreaseLiquidityParams calldata params)
                          external
                          payable
                          returns (
                              uint128 liquidity,
                              uint256 amount0,
                              uint256 amount1
                          );
                      struct DecreaseLiquidityParams {
                          uint256 tokenId;
                          uint128 liquidity;
                          uint256 amount0Min;
                          uint256 amount1Min;
                          uint256 deadline;
                      }
                      /// @notice Decreases the amount of liquidity in a position and accounts it to the position
                      /// @param params tokenId The ID of the token for which liquidity is being decreased,
                      /// amount The amount by which liquidity will be decreased,
                      /// amount0Min The minimum amount of token0 that should be accounted for the burned liquidity,
                      /// amount1Min The minimum amount of token1 that should be accounted for the burned liquidity,
                      /// deadline The time by which the transaction must be included to effect the change
                      /// @return amount0 The amount of token0 accounted to the position's tokens owed
                      /// @return amount1 The amount of token1 accounted to the position's tokens owed
                      function decreaseLiquidity(DecreaseLiquidityParams calldata params)
                          external
                          payable
                          returns (uint256 amount0, uint256 amount1);
                      struct CollectParams {
                          uint256 tokenId;
                          address recipient;
                          uint128 amount0Max;
                          uint128 amount1Max;
                      }
                      /// @notice Collects up to a maximum amount of fees owed to a specific position to the recipient
                      /// @param params tokenId The ID of the NFT for which tokens are being collected,
                      /// recipient The account that should receive the tokens,
                      /// amount0Max The maximum amount of token0 to collect,
                      /// amount1Max The maximum amount of token1 to collect
                      /// @return amount0 The amount of fees collected in token0
                      /// @return amount1 The amount of fees collected in token1
                      function collect(CollectParams calldata params) external payable returns (uint256 amount0, uint256 amount1);
                      /// @notice Burns a token ID, which deletes it from the NFT contract. The token must have 0 liquidity and all tokens
                      /// must be collected first.
                      /// @param tokenId The ID of the token that is being burned
                      function burn(uint256 tokenId) external payable;
                  }
                  // SPDX-License-Identifier: MIT
                  pragma solidity ^0.7.0;
                  import "./IERC721.sol";
                  /**
                   * @title ERC-721 Non-Fungible Token Standard, optional metadata extension
                   * @dev See https://eips.ethereum.org/EIPS/eip-721
                   */
                  interface IERC721Metadata is IERC721 {
                      /**
                       * @dev Returns the token collection name.
                       */
                      function name() external view returns (string memory);
                      /**
                       * @dev Returns the token collection symbol.
                       */
                      function symbol() external view returns (string memory);
                      /**
                       * @dev Returns the Uniform Resource Identifier (URI) for `tokenId` token.
                       */
                      function tokenURI(uint256 tokenId) external view returns (string memory);
                  }
                  // SPDX-License-Identifier: MIT
                  pragma solidity ^0.7.0;
                  import "./IERC721.sol";
                  /**
                   * @title ERC-721 Non-Fungible Token Standard, optional enumeration extension
                   * @dev See https://eips.ethereum.org/EIPS/eip-721
                   */
                  interface IERC721Enumerable is IERC721 {
                      /**
                       * @dev Returns the total amount of tokens stored by the contract.
                       */
                      function totalSupply() external view returns (uint256);
                      /**
                       * @dev Returns a token ID owned by `owner` at a given `index` of its token list.
                       * Use along with {balanceOf} to enumerate all of ``owner``'s tokens.
                       */
                      function tokenOfOwnerByIndex(address owner, uint256 index) external view returns (uint256 tokenId);
                      /**
                       * @dev Returns a token ID at a given `index` of all the tokens stored by the contract.
                       * Use along with {totalSupply} to enumerate all tokens.
                       */
                      function tokenByIndex(uint256 index) external view returns (uint256);
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.7.5;
                  pragma abicoder v2;
                  /// @title Creates and initializes V3 Pools
                  /// @notice Provides a method for creating and initializing a pool, if necessary, for bundling with other methods that
                  /// require the pool to exist.
                  interface IPoolInitializer {
                      /// @notice Creates a new pool if it does not exist, then initializes if not initialized
                      /// @dev This method can be bundled with others via IMulticall for the first action (e.g. mint) performed against a pool
                      /// @param token0 The contract address of token0 of the pool
                      /// @param token1 The contract address of token1 of the pool
                      /// @param fee The fee amount of the v3 pool for the specified token pair
                      /// @param sqrtPriceX96 The initial square root price of the pool as a Q64.96 value
                      /// @return pool Returns the pool address based on the pair of tokens and fee, will return the newly created pool address if necessary
                      function createAndInitializePoolIfNecessary(
                          address token0,
                          address token1,
                          uint24 fee,
                          uint160 sqrtPriceX96
                      ) external payable returns (address pool);
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity >=0.7.5;
                  import '@openzeppelin/contracts/token/ERC721/IERC721.sol';
                  /// @title ERC721 with permit
                  /// @notice Extension to ERC721 that includes a permit function for signature based approvals
                  interface IERC721Permit is IERC721 {
                      /// @notice The permit typehash used in the permit signature
                      /// @return The typehash for the permit
                      function PERMIT_TYPEHASH() external pure returns (bytes32);
                      /// @notice The domain separator used in the permit signature
                      /// @return The domain seperator used in encoding of permit signature
                      function DOMAIN_SEPARATOR() external view returns (bytes32);
                      /// @notice Approve of a specific token ID for spending by spender via signature
                      /// @param spender The account that is being approved
                      /// @param tokenId The ID of the token that is being approved for spending
                      /// @param deadline The deadline timestamp by which the call must be mined for the approve to work
                      /// @param v Must produce valid secp256k1 signature from the holder along with `r` and `s`
                      /// @param r Must produce valid secp256k1 signature from the holder along with `v` and `s`
                      /// @param s Must produce valid secp256k1 signature from the holder along with `r` and `v`
                      function permit(
                          address spender,
                          uint256 tokenId,
                          uint256 deadline,
                          uint8 v,
                          bytes32 r,
                          bytes32 s
                      ) external payable;
                  }
                  // SPDX-License-Identifier: MIT
                  pragma solidity ^0.7.0;
                  import "../../introspection/IERC165.sol";
                  /**
                   * @dev Required interface of an ERC721 compliant contract.
                   */
                  interface IERC721 is IERC165 {
                      /**
                       * @dev Emitted when `tokenId` token is transferred from `from` to `to`.
                       */
                      event Transfer(address indexed from, address indexed to, uint256 indexed tokenId);
                      /**
                       * @dev Emitted when `owner` enables `approved` to manage the `tokenId` token.
                       */
                      event Approval(address indexed owner, address indexed approved, uint256 indexed tokenId);
                      /**
                       * @dev Emitted when `owner` enables or disables (`approved`) `operator` to manage all of its assets.
                       */
                      event ApprovalForAll(address indexed owner, address indexed operator, bool approved);
                      /**
                       * @dev Returns the number of tokens in ``owner``'s account.
                       */
                      function balanceOf(address owner) external view returns (uint256 balance);
                      /**
                       * @dev Returns the owner of the `tokenId` token.
                       *
                       * Requirements:
                       *
                       * - `tokenId` must exist.
                       */
                      function ownerOf(uint256 tokenId) external view returns (address owner);
                      /**
                       * @dev Safely transfers `tokenId` token from `from` to `to`, checking first that contract recipients
                       * are aware of the ERC721 protocol to prevent tokens from being forever locked.
                       *
                       * Requirements:
                       *
                       * - `from` cannot be the zero address.
                       * - `to` cannot be the zero address.
                       * - `tokenId` token must exist and be owned by `from`.
                       * - If the caller is not `from`, it must be have been allowed to move this token by either {approve} or {setApprovalForAll}.
                       * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
                       *
                       * Emits a {Transfer} event.
                       */
                      function safeTransferFrom(address from, address to, uint256 tokenId) external;
                      /**
                       * @dev Transfers `tokenId` token from `from` to `to`.
                       *
                       * WARNING: Usage of this method is discouraged, use {safeTransferFrom} whenever possible.
                       *
                       * Requirements:
                       *
                       * - `from` cannot be the zero address.
                       * - `to` cannot be the zero address.
                       * - `tokenId` token must be owned by `from`.
                       * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
                       *
                       * Emits a {Transfer} event.
                       */
                      function transferFrom(address from, address to, uint256 tokenId) external;
                      /**
                       * @dev Gives permission to `to` to transfer `tokenId` token to another account.
                       * The approval is cleared when the token is transferred.
                       *
                       * Only a single account can be approved at a time, so approving the zero address clears previous approvals.
                       *
                       * Requirements:
                       *
                       * - The caller must own the token or be an approved operator.
                       * - `tokenId` must exist.
                       *
                       * Emits an {Approval} event.
                       */
                      function approve(address to, uint256 tokenId) external;
                      /**
                       * @dev Returns the account approved for `tokenId` token.
                       *
                       * Requirements:
                       *
                       * - `tokenId` must exist.
                       */
                      function getApproved(uint256 tokenId) external view returns (address operator);
                      /**
                       * @dev Approve or remove `operator` as an operator for the caller.
                       * Operators can call {transferFrom} or {safeTransferFrom} for any token owned by the caller.
                       *
                       * Requirements:
                       *
                       * - The `operator` cannot be the caller.
                       *
                       * Emits an {ApprovalForAll} event.
                       */
                      function setApprovalForAll(address operator, bool _approved) external;
                      /**
                       * @dev Returns if the `operator` is allowed to manage all of the assets of `owner`.
                       *
                       * See {setApprovalForAll}
                       */
                      function isApprovedForAll(address owner, address operator) external view returns (bool);
                      /**
                        * @dev Safely transfers `tokenId` token from `from` to `to`.
                        *
                        * Requirements:
                        *
                        * - `from` cannot be the zero address.
                        * - `to` cannot be the zero address.
                        * - `tokenId` token must exist and be owned by `from`.
                        * - If the caller is not `from`, it must be approved to move this token by either {approve} or {setApprovalForAll}.
                        * - If `to` refers to a smart contract, it must implement {IERC721Receiver-onERC721Received}, which is called upon a safe transfer.
                        *
                        * Emits a {Transfer} event.
                        */
                      function safeTransferFrom(address from, address to, uint256 tokenId, bytes calldata data) external;
                  }
                  // SPDX-License-Identifier: MIT
                  pragma solidity ^0.7.0;
                  /**
                   * @dev Interface of the ERC165 standard, as defined in the
                   * https://eips.ethereum.org/EIPS/eip-165[EIP].
                   *
                   * Implementers can declare support of contract interfaces, which can then be
                   * queried by others ({ERC165Checker}).
                   *
                   * For an implementation, see {ERC165}.
                   */
                  interface IERC165 {
                      /**
                       * @dev Returns true if this contract implements the interface defined by
                       * `interfaceId`. See the corresponding
                       * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
                       * to learn more about how these ids are created.
                       *
                       * This function call must use less than 30 000 gas.
                       */
                      function supportsInterface(bytes4 interfaceId) external view returns (bool);
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity =0.7.6;
                  pragma abicoder v2;
                  import '../interfaces/IMulticall.sol';
                  /// @title Multicall
                  /// @notice Enables calling multiple methods in a single call to the contract
                  abstract contract Multicall is IMulticall {
                      /// @inheritdoc IMulticall
                      function multicall(bytes[] calldata data) public payable override returns (bytes[] memory results) {
                          results = new bytes[](data.length);
                          for (uint256 i = 0; i < data.length; i++) {
                              (bool success, bytes memory result) = address(this).delegatecall(data[i]);
                              if (!success) {
                                  // Next 5 lines from https://ethereum.stackexchange.com/a/83577
                                  if (result.length < 68) revert();
                                  assembly {
                                      result := add(result, 0x04)
                                  }
                                  revert(abi.decode(result, (string)));
                              }
                              results[i] = result;
                          }
                      }
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity =0.7.6;
                  import '@uniswap/v3-periphery/contracts/base/PeripheryValidation.sol';
                  abstract contract PeripheryValidationExtended is PeripheryValidation {
                      modifier checkPreviousBlockhash(bytes32 previousBlockhash) {
                          require(blockhash(block.number - 1) == previousBlockhash, 'Blockhash');
                          _;
                      }
                  }
                  // SPDX-License-Identifier: GPL-2.0-or-later
                  pragma solidity =0.7.6;
                  import './BlockTimestamp.sol';
                  abstract contract PeripheryValidation is BlockTimestamp {
                      modifier checkDeadline(uint256 deadline) {
                          require(_blockTimestamp() <= deadline, 'Transaction too old');
                          _;
                      }
                  }
                  

                  File 2 of 7: SphynxToken
                  // SPDX-License-Identifier: MIT
                  pragma solidity 0.6.12;
                  import '@sphynxswap/sphynx-swap-lib/contracts/access/Manageable.sol';
                  import '@sphynxswap/sphynx-swap-lib/contracts/token/BEP20/BEP20.sol';
                  import '@sphynxswap/sphynx-swap-lib/contracts/token/BEP20/IBEP20.sol';
                  import '@sphynxswap/sphynx-swap-lib/contracts/token/BEP20/SafeBEP20.sol';
                  import '@sphynxswap/swap-core/contracts/interfaces/ISphynxPair.sol';
                  import '@sphynxswap/swap-core/contracts/interfaces/ISphynxFactory.sol';
                  import '@sphynxswap/swap-periphery/contracts/interfaces/ISphynxRouter02.sol';
                  interface AggregatorV3Interface {
                  \tfunction decimals() external view returns (uint8);
                  \tfunction description() external view returns (string memory);
                  \tfunction version() external view returns (uint256);
                  \t// getRoundData and latestRoundData should both raise "No data present"
                  \t// if they do not have data to report, instead of returning unset values
                  \t// which could be misinterpreted as actual reported values.
                  \tfunction getRoundData(uint80 _roundId)
                  \t\texternal
                  \t\tview
                  \t\treturns (
                  \t\t\tuint80 roundId,
                  \t\t\tint256 answer,
                  \t\t\tuint256 startedAt,
                  \t\t\tuint256 updatedAt,
                  \t\t\tuint80 answeredInRound
                  \t\t);
                  \tfunction latestRoundData()
                  \t\texternal
                  \t\tview
                  \t\treturns (
                  \t\t\tuint80 roundId,
                  \t\t\tint256 answer,
                  \t\t\tuint256 startedAt,
                  \t\t\tuint256 updatedAt,
                  \t\t\tuint80 answeredInRound
                  \t\t);
                  }
                  contract SphynxToken is BEP20, Manageable {
                  \tusing SafeMath for uint256;
                  \tusing SafeBEP20 for IBEP20;
                  \tISphynxRouter02 public sphynxSwapRouter;
                  \taddress public sphynxSwapPair;
                  \tbool private swapping;
                  \taddress public masterChef;
                  \taddress public sphynxBridge;
                  \taddress payable public marketingWallet = payable(0x3D458e65828d031B46579De28e9BBAAeb2729064);
                  \taddress payable public developmentWallet = payable(0x7dB8380C7A017F82CC1d2DC7F8F1dE2d29Fd1df6);
                  \taddress public lotteryAddress;
                  \tuint256 public usdAmountToSwap = 500;
                  \tuint256 public marketingFee;
                  \tuint256 public developmentFee;
                  \tuint256 public lotteryFee;
                  \tuint256 public totalFees;
                  \tuint256 public blockNumber;
                  \tbool public SwapAndLiquifyEnabled = false;
                  \tbool public sendToLottery = false;
                  \tbool public stopTrade = false;
                  \tbool public claimable = true;
                  \tuint256 public maxTxAmount = 800000000 * (10 ** 18); // Initial Max Tx Amount
                  \tmapping(address => bool) signers;
                  \tmapping(uint256 => address) signersArray;
                  \tmapping(address => bool) stopTradeSign;
                  \tAggregatorV3Interface internal priceFeed;
                  \t// exlcude from fees and max transaction amount
                  \tmapping(address => bool) private _isExcludedFromFees;
                  \t// getting fee addresses
                  \tmapping(address => bool) public _isGetFees;
                  \t// store addresses that are automated market maker pairs. Any transfer to these addresses
                  \t// could be subject to a maximum transfer amount
                  \tmapping(address => bool) public automatedMarketMakerPairs;
                  \tuint256 private constant _NOT_ENTERED = 1;
                      uint256 private constant _ENTERED = 2;
                      uint256 private _status;
                  \tmodifier onlyMasterChefAndBridge() {
                  \t\trequire(msg.sender == masterChef || msg.sender == sphynxBridge, 'Permission Denied');
                  \t\t_;
                  \t}
                  \tmodifier onlySigner() {
                  \t\trequire(signers[msg.sender], 'not-a-signer');
                  \t\t_;
                  \t}
                  \tmodifier nonReentrant() {
                          // On the first call to nonReentrant, _notEntered will be true
                          require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
                          // Any calls to nonReentrant after this point will fail
                          _status = _ENTERED;
                          _;
                          // By storing the original value once again, a refund is triggered (see
                          // https://eips.ethereum.org/EIPS/eip-2200)
                          _status = _NOT_ENTERED;
                      }
                  \t// Contract Events
                  \tevent ExcludeFromFees(address indexed account, bool isExcluded);
                  \tevent GetFee(address indexed account, bool isGetFee);
                  \tevent ExcludeMultipleAccountsFromFees(address[] accounts, bool isExcluded);
                  \tevent SetAutomatedMarketMakerPair(address indexed pair, bool indexed value);
                  \tevent MarketingWalletUpdated(address indexed newMarketingWallet, address indexed oldMarketingWallet);
                  \tevent DevelopmentWalletUpdated(address indexed newDevelopmentWallet, address indexed oldDevelopmentWallet);
                  \tevent LotteryAddressUpdated(address indexed newLotteryAddress, address indexed oldLotteryAddress);
                  \tevent UpdateSphynxSwapRouter(address indexed newAddress, address indexed oldAddress);
                  \tevent SwapAndLiquify(uint256 tokensSwapped, uint256 nativeReceived, uint256 tokensIntoLiqudity);
                  \tevent UpdateSwapAndLiquify(bool value);
                  \tevent UpdateSendToLottery(bool value);
                  \tevent SetMarketingFee(uint256 value);
                  \tevent SetDevelopmentFee(uint256 value);
                  \tevent SetLotteryFee(uint256 value);
                  \tevent SetAllFeeToZero(uint256 marketingFee, uint256 developmentFee, uint256 lotteryFee);
                  \tevent MaxFees(uint256 marketingFee, uint256 developmentFee, uint256 lotteryFee);
                  \tevent SetUsdAmountToSwap(uint256 usdAmountToSwap);
                  \tevent SetBlockNumber(uint256 blockNumber);
                  \tevent UpdateMasterChef(address masterChef);
                  \tevent UpdateSphynxBridge(address sphynxBridge);
                  \tevent UpdateMaxTxAmount(uint256 txAmount);
                  \tconstructor() public BEP20('Sphynx ETH', 'SPHYNX') {
                  \t\tuint256 _marketingFee = 5;
                  \t\tuint256 _developmentFee = 5;
                  \t\tuint256 _lotteryFee = 1;
                  \t\tmarketingFee = _marketingFee;
                  \t\tdevelopmentFee = _developmentFee;
                  \t\tlotteryFee = _lotteryFee;
                  \t\ttotalFees = _marketingFee.add(_developmentFee);
                  \t\tblockNumber = 0;
                  \t\tISphynxRouter02 _sphynxSwapRouter = ISphynxRouter02(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D); // mainnet
                  \t\t// Create a sphynxswap pair for SPHYNX
                  \t\taddress _sphynxSwapPair = ISphynxFactory(_sphynxSwapRouter.factory()).createPair(address(this), _sphynxSwapRouter.WETH());
                  \t\tsphynxSwapRouter = _sphynxSwapRouter;
                  \t\tsphynxSwapPair = _sphynxSwapPair;
                  \t\t_setAutomatedMarketMakerPair(sphynxSwapPair, true);
                  \t\t// exclude from paying fees or having max transaction amount
                  \t\texcludeFromFees(marketingWallet, true);
                  \t\texcludeFromFees(developmentWallet, true);
                  \t\texcludeFromFees(address(this), true);
                  \t\texcludeFromFees(owner(), true);
                  \t\t// set getFee addresses
                  \t\t_isGetFees[address(_sphynxSwapRouter)] = true;
                  \t\t_isGetFees[_sphynxSwapPair] = true;
                  \t\tpriceFeed = AggregatorV3Interface(0x5f4eC3Df9cbd43714FE2740f5E3616155c5b8419);
                  \t\t_mint(owner(), 800000000 * (10**18));
                  \t\t_status = _NOT_ENTERED;
                  \t\t//multi-sign-wallets
                  \t\tsigners[0x35BfE8dA53F94d6711F111790643D2D403992b56] = true;
                  \t\tsigners[0x96C463B615228981A2c30B842E8A8e4e933CEc46] = true;
                  \t\tsigners[0x7278fC9C49A2B6bd072b9d47E3c903ef0e12bb83] = true;
                  \t\tsignersArray[0] = 0x35BfE8dA53F94d6711F111790643D2D403992b56;
                  \t\tsignersArray[1] = 0x96C463B615228981A2c30B842E8A8e4e933CEc46;
                  \t\tsignersArray[2] = 0x7278fC9C49A2B6bd072b9d47E3c903ef0e12bb83;
                  \t}
                  \treceive() external payable {}
                  \t// mint function for masterchef;
                  \tfunction mint(address to, uint256 amount) public onlyMasterChefAndBridge {
                  \t\t_mint(to, amount);
                  \t}
                  \tfunction updateSwapAndLiquifiy(bool value) public onlyManager {
                  \t\tSwapAndLiquifyEnabled = value;
                  \t\temit UpdateSwapAndLiquify(value);
                  \t}
                  \tfunction updateSendToLottery(bool value) public onlyManager {
                  \t\tsendToLottery = value;
                  \t\temit UpdateSendToLottery(value);
                  \t}
                  \tfunction setMarketingFee(uint256 value) external onlyManager {
                  \t\trequire(value <= 5, 'SPHYNX: Invalid marketingFee');
                  \t\tmarketingFee = value;
                  \t\ttotalFees = marketingFee.add(developmentFee);
                  \t\temit SetMarketingFee(value);
                  \t}
                  \tfunction setDevelopmentFee(uint256 value) external onlyManager {
                  \t\trequire(value <= 5, 'SPHYNX: Invalid developmentFee');
                  \t\tdevelopmentFee = value;
                  \t\ttotalFees = marketingFee.add(developmentFee);
                  \t\temit SetDevelopmentFee(value);
                  \t}
                  \tfunction setLotteryFee(uint256 value) external onlyManager {
                  \t\trequire(value <= 1, 'SPHYNX: Invalid lotteryFee');
                  \t\tlotteryFee = value;
                  \t\temit SetLotteryFee(value);
                  \t}
                  \tfunction setAllFeeToZero() external onlyOwner {
                  \t\tmarketingFee = 0;
                  \t\tdevelopmentFee = 0;
                  \t\tlotteryFee = 0;
                  \t\ttotalFees = 0;
                  \t\temit SetAllFeeToZero(marketingFee, developmentFee, lotteryFee);
                  \t}
                  \tfunction maxFees() external onlyOwner {
                  \t\tmarketingFee = 5;
                  \t\tdevelopmentFee = 5;
                  \t\tlotteryFee = 1;
                  \t\ttotalFees = marketingFee.add(developmentFee);
                  \t\temit MaxFees(marketingFee, developmentFee, lotteryFee);
                  \t}
                  \tfunction updateSphynxSwapRouter(address newAddress) public onlyManager {
                  \t\trequire(newAddress != address(sphynxSwapRouter), 'SPHYNX: The router already has that address');
                  \t\temit UpdateSphynxSwapRouter(newAddress, address(sphynxSwapRouter));
                  \t\tsphynxSwapRouter = ISphynxRouter02(newAddress);
                  \t\taddress _sphynxSwapPair;
                  \t\t_sphynxSwapPair = ISphynxFactory(sphynxSwapRouter.factory()).getPair(address(this), sphynxSwapRouter.WETH());
                  \t\tif(_sphynxSwapPair == address(0)) {
                  \t\t\t_sphynxSwapPair = ISphynxFactory(sphynxSwapRouter.factory()).createPair(address(this), sphynxSwapRouter.WETH());
                  \t\t}
                  \t\t_setAutomatedMarketMakerPair(sphynxSwapPair, false);
                  \t\tsphynxSwapPair = _sphynxSwapPair;
                  \t\t_setAutomatedMarketMakerPair(sphynxSwapPair, true);
                  \t}
                  \tfunction updateMasterChef(address _masterChef) public onlyManager {
                  \t\trequire(masterChef != _masterChef, 'SPHYNX: MasterChef already exists!');
                  \t\tmasterChef = _masterChef;
                  \t\temit UpdateMasterChef(_masterChef);
                  \t}
                  \tfunction updateSphynxBridge(address _sphynxBridge) public onlyManager {
                  \t\trequire(sphynxBridge != _sphynxBridge, 'SPHYNX: SphynxBridge already exists!');
                  \t\t_isExcludedFromFees[sphynxBridge] = false;
                  \t\tsphynxBridge = _sphynxBridge;
                  \t\t_isExcludedFromFees[sphynxBridge] = true;
                  \t\temit UpdateSphynxBridge(_sphynxBridge);
                  \t}
                  \tfunction excludeFromFees(address account, bool excluded) public onlyManager {
                  \t\trequire(_isExcludedFromFees[account] != excluded, "SPHYNX: Account is already the value of 'excluded'");
                  \t\t_isExcludedFromFees[account] = excluded;
                  \t\temit ExcludeFromFees(account, excluded);
                  \t}
                  \tfunction setFeeAccount(address account, bool isGetFee) public onlyManager {
                  \t\trequire(_isGetFees[account] != isGetFee, "SPHYNX: Account is already the value of 'isGetFee'");
                  \t\t_isGetFees[account] = isGetFee;
                  \t\temit GetFee(account, isGetFee);
                  \t}
                  \tfunction excludeMultipleAccountsFromFees(address[] calldata accounts, bool excluded) public onlyOwner {
                  \t\tfor (uint256 i = 0; i < accounts.length; i++) {
                  \t\t\t_isExcludedFromFees[accounts[i]] = excluded;
                  \t\t}
                  \t\temit ExcludeMultipleAccountsFromFees(accounts, excluded);
                  \t}
                  \tfunction setAutomatedMarketMakerPair(address pair, bool value) public onlyManager {
                  \t\t_setAutomatedMarketMakerPair(pair, value);
                  \t}
                  \tfunction _setAutomatedMarketMakerPair(address pair, bool value) private {
                  \t\trequire(automatedMarketMakerPairs[pair] != value, 'SPHYNX: Automated market maker pair is already set to that value');
                  \t\tautomatedMarketMakerPairs[pair] = value;
                  \t\temit SetAutomatedMarketMakerPair(pair, value);
                  \t}
                  \tfunction setUsdAmountToSwap(uint256 _usdAmount) public onlyManager {
                  \t\tusdAmountToSwap = _usdAmount;
                  \t\temit SetUsdAmountToSwap(usdAmountToSwap);
                  \t}
                  \tfunction updateMarketingWallet(address newMarketingWallet) public onlyManager {
                  \t\trequire(newMarketingWallet != marketingWallet, 'SPHYNX: The marketing wallet is already this address');
                  \t\texcludeFromFees(newMarketingWallet, true);
                  \t\texcludeFromFees(marketingWallet, false);
                  \t\temit MarketingWalletUpdated(newMarketingWallet, marketingWallet);
                  \t\tmarketingWallet = payable(newMarketingWallet);
                  \t}
                  \tfunction updateDevelopmentgWallet(address newDevelopmentWallet) public onlyManager {
                  \t\trequire(newDevelopmentWallet != developmentWallet, 'SPHYNX: The development wallet is already this address');
                  \t\texcludeFromFees(newDevelopmentWallet, true);
                  \t\texcludeFromFees(developmentWallet, false);
                  \t\temit DevelopmentWalletUpdated(newDevelopmentWallet, developmentWallet);
                  \t\tdevelopmentWallet = payable(newDevelopmentWallet);
                  \t}
                  \tfunction updateLotteryAddress(address newLotteryAddress) public onlyManager {
                  \t\trequire(newLotteryAddress != lotteryAddress, 'SPHYNX: The lottery wallet is already this address');
                  \t\texcludeFromFees(newLotteryAddress, true);
                  \t\texcludeFromFees(lotteryAddress, false);
                  \t\temit LotteryAddressUpdated(newLotteryAddress, lotteryAddress);
                  \t\tlotteryAddress = newLotteryAddress;
                  \t}
                  \tfunction setBlockNumber() public onlyOwner {
                  \t\tblockNumber = block.number;
                  \t\temit SetBlockNumber(blockNumber);
                  \t}
                  \tfunction updateMaxTxAmount(uint256 _amount) public onlyManager {
                  \t\tmaxTxAmount = _amount;
                  \t\temit UpdateMaxTxAmount(_amount);
                  \t}
                  \tfunction updateTokenClaim(bool _claim) public onlyManager {
                  \t\tclaimable = _claim;
                  \t}
                  \tfunction updateStopTrade(bool _value) external onlySigner {
                  \t\trequire(stopTrade != _value, 'already-set');
                  \t\trequire(!stopTradeSign[msg.sender], 'already-sign');
                  \t\tstopTradeSign[msg.sender] = true;
                          if (
                              stopTradeSign[signersArray[0]] &&
                              stopTradeSign[signersArray[1]] &&
                              stopTradeSign[signersArray[2]]
                          ) {
                  \t\t\tstopTrade = _value;
                  \t\t\tstopTradeSign[signersArray[0]] = false;
                  \t\t\tstopTradeSign[signersArray[1]] = false;
                  \t\t\tstopTradeSign[signersArray[2]] = false;
                  \t\t}
                  \t}
                  \tfunction updateSignerWallet(address _signer) external onlySigner {
                  \t\tsigners[msg.sender] = false;
                  \t\tsigners[_signer] = true;
                  \t\tfor(uint i = 0; i < 3; i++) {
                  \t\t\tif(signersArray[i] == msg.sender) {
                  \t\t\t\tsignersArray[i] = _signer;
                  \t\t\t}
                  \t\t}
                  \t}
                  \tfunction isExcludedFromFees(address account) public view returns (bool) {
                  \t\treturn _isExcludedFromFees[account];
                  \t}
                  \tfunction _transfer(
                  \t\taddress from,
                  \t\taddress to,
                  \t\tuint256 amount
                  \t) internal override {
                  \t\trequire(from != address(0), 'BEP20: transfer from the zero address');
                  \t\trequire(to != address(0), 'BEP20: transfer to the zero address');
                  \t\trequire(!stopTrade, 'trade-stopped');
                  \t\trequire(amount <= maxTxAmount, 'max-tx-amount-overflow');
                  \t\tif (amount == 0) {
                  \t\t\tsuper._transfer(from, to, 0);
                  \t\t\treturn;
                  \t\t}
                          if(SwapAndLiquifyEnabled) {
                              uint256 contractTokenBalance = balanceOf(address(this));
                              uint256 nativeTokenAmount = _getTokenAmountFromNative();
                  \t\t    bool canSwap = contractTokenBalance >= nativeTokenAmount;
                              if (canSwap && !swapping && !automatedMarketMakerPairs[from]) {
                                  swapping = true;
                                  // Set number of tokens to sell to nativeTokenAmount
                                  contractTokenBalance = nativeTokenAmount;
                                  swapTokens(contractTokenBalance);
                                  swapping = false;
                              }
                          }
                  \t\t// indicates if fee should be deducted from transfer
                  \t\tbool takeFee = true;
                  \t\t// if any account belongs to _isExcludedFromFee account then remove the fee
                  \t\tif (_isExcludedFromFees[from] || _isExcludedFromFees[to]) {
                  \t\t\ttakeFee = false;
                  \t\t}
                  \t\tif (takeFee) {
                  \t\t\tif (block.number - blockNumber <= 10) {
                  \t\t\t\tuint256 afterBalance = balanceOf(to) + amount;
                  \t\t\t\trequire(afterBalance <= 250000 * (10**18), 'Owned amount exceeds the maxOwnedAmount');
                  \t\t\t}
                  \t\t\tuint256 fees;
                  \t\t\tif (_isGetFees[from] || _isGetFees[to]) {
                  \t\t\t\tif (block.number - blockNumber <= 5) {
                  \t\t\t\t\tfees = amount.mul(99).div(10**2);
                  \t\t\t\t} else {
                  \t\t\t\t\tfees = amount.mul(totalFees).div(10**2);
                  \t\t\t\t\tif (sendToLottery) {
                  \t\t\t\t\t\tuint256 lotteryAmount = amount.mul(lotteryFee).div(10**2);
                  \t\t\t\t\t\tamount = amount.sub(lotteryAmount);
                  \t\t\t\t\t\tsuper._transfer(from, lotteryAddress, lotteryAmount);
                  \t\t\t\t\t}
                  \t\t\t\t}
                  \t\t\t\tamount = amount.sub(fees);
                  \t\t\t\tsuper._transfer(from, address(this), fees);
                  \t\t\t}
                  \t\t}
                  \t\tsuper._transfer(from, to, amount);
                  \t}
                  \tfunction swapTokens(uint256 tokenAmount) private {
                  \t\tswapTokensForNative(tokenAmount);
                  \t\tuint256 swappedNative = address(this).balance;
                  \t\tuint256 marketingNative = swappedNative.mul(marketingFee).div(totalFees);
                  \t\tuint256 developmentNative = swappedNative.sub(marketingNative);
                  \t\ttransferNativeToMarketingWallet(marketingNative);
                  \t\ttransferNativeToDevelopmentWallet(developmentNative);
                  \t}
                  \t// Swap tokens on PacakeSwap
                  \tfunction swapTokensForNative(uint256 tokenAmount) private {
                  \t\t// generate the sphynxswap pair path of token -> WETH
                  \t\taddress[] memory path = new address[](2);
                  \t\tpath[0] = address(this);
                  \t\tpath[1] = sphynxSwapRouter.WETH();
                  \t\t_approve(address(this), address(sphynxSwapRouter), tokenAmount);
                  \t\t// make the swap
                  \t\tsphynxSwapRouter.swapExactTokensForETHSupportingFeeOnTransferTokens(
                  \t\t\ttokenAmount,
                  \t\t\t0, // accept any amount of Native
                  \t\t\tpath,
                  \t\t\taddress(this),
                  \t\t\tblock.timestamp
                  \t\t);
                  \t}
                  \tfunction getNativeAmountFromUSD() public view returns (uint256 amount) {
                  \t\t(
                              uint80 roundID, 
                              int price,
                              uint startedAt,
                              uint timeStamp,
                              uint80 answeredInRound
                          ) = priceFeed.latestRoundData();
                          amount = usdAmountToSwap.mul(10 ** 26).div(uint256(price));
                  \t}
                  \tfunction _getTokenAmountFromNative() internal view returns (uint256) {
                  \t\tuint256 tokenAmount;
                  \t\taddress[] memory path = new address[](2);
                  \t\tpath[0] = sphynxSwapRouter.WETH();
                  \t\tpath[1] = address(this);
                  \t\tuint256 nativeAmountToSwap = getNativeAmountFromUSD();
                  \t\tuint256[] memory amounts = sphynxSwapRouter.getAmountsOut(nativeAmountToSwap, path);
                  \t\ttokenAmount = amounts[1];
                  \t\treturn tokenAmount;
                  \t}
                  \tfunction transferNativeToMarketingWallet(uint256 amount) private {
                  \t\tmarketingWallet.transfer(amount);
                  \t}
                  \tfunction transferNativeToDevelopmentWallet(uint256 amount) private {
                  \t\tdevelopmentWallet.transfer(amount);
                  \t}
                  }// SPDX-License-Identifier: GPL-3.0-or-later
                  pragma solidity >=0.4.0;
                  import '../GSN/Context.sol';
                  /**
                   * @dev Contract module which provides a basic access control mechanism, where
                   * there is an account (an manager) that can be granted exclusive access to
                   * specific functions.
                   *
                   * By default, the manager account will be the one that deploys the contract. This
                   * can later be changed with {transferManagement}.
                   *
                   * This module is used through inheritance. It will make available the modifier
                   * `onlyManager`, which can be applied to your functions to restrict their use to
                   * the manager.
                   */
                  contract Manageable is Context {
                      address private _manager;
                      event ManagementTransferred(address indexed previousManager, address indexed newManager);
                      /**
                       * @dev Initializes the contract setting the deployer as the initial manager.
                       */
                      constructor() internal {
                          address msgSender = _msgSender();
                          _manager = msgSender;
                          emit ManagementTransferred(address(0), msgSender);
                      }
                      /**
                       * @dev Returns the address of the current manager.
                       */
                      function manager() public view returns (address) {
                          return _manager;
                      }
                      /**
                       * @dev Throws if called by any account other than the manager.
                       */
                      modifier onlyManager() {
                          require(_manager == _msgSender(), 'Manageable: caller is not the manager');
                          _;
                      }
                      /**
                       * @dev Leaves the contract without manager. It will not be possible to call
                       * `onlyManager` functions anymore. Can only be called by the current manager.
                       *
                       * NOTE: Renouncing management will leave the contract without an manager,
                       * thereby removing any functionality that is only available to the manager.
                       */
                      function renounceManagement() public onlyManager {
                          emit ManagementTransferred(_manager, address(0));
                          _manager = address(0);
                      }
                      /**
                       * @dev Transfers management of the contract to a new account (`newManager`).
                       * Can only be called by the current manager.
                       */
                      function transferManagement(address newManager) public onlyManager {
                          _transferManagement(newManager);
                      }
                      /**
                       * @dev Transfers management of the contract to a new account (`newManager`).
                       */
                      function _transferManagement(address newManager) internal {
                          require(newManager != address(0), 'Manageable: new manager is the zero address');
                          emit ManagementTransferred(_manager, newManager);
                          _manager = newManager;
                      }
                  }
                  // SPDX-License-Identifier: MIT
                  pragma solidity >=0.4.0;
                  import '../../access/Ownable.sol';
                  import '../../GSN/Context.sol';
                  import './IBEP20.sol';
                  import '../../math/SafeMath.sol';
                  import '../../utils/Address.sol';
                  /**
                   * @dev Implementation of the {IBEP20} 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 {BEP20PresetMinterPauser}.
                   *
                   * TIP: For a detailed writeup see our guide
                   * https://forum.zeppelin.solutions/t/how-to-implement-BEP20-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 BEP20 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 {IBEP20-approve}.
                   */
                  contract BEP20 is Context, IBEP20, Ownable {
                      using SafeMath for uint256;
                      using Address for address;
                      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) public {
                          _name = name;
                          _symbol = symbol;
                          _decimals = 18;
                      }
                      /**
                       * @dev Returns the bep token owner.
                       */
                      function getOwner() external override view returns (address) {
                          return owner();
                      }
                      /**
                       * @dev Returns the token name.
                       */
                      function name() public override view returns (string memory) {
                          return _name;
                      }
                      /**
                       * @dev Returns the token decimals.
                       */
                      function decimals() public override view returns (uint8) {
                          return _decimals;
                      }
                      /**
                       * @dev Returns the token symbol.
                       */
                      function symbol() public override view returns (string memory) {
                          return _symbol;
                      }
                      /**
                       * @dev See {BEP20-totalSupply}.
                       */
                      function totalSupply() public override view returns (uint256) {
                          return _totalSupply;
                      }
                      /**
                       * @dev See {BEP20-balanceOf}.
                       */
                      function balanceOf(address account) public override view returns (uint256) {
                          return _balances[account];
                      }
                      /**
                       * @dev See {BEP20-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 override returns (bool) {
                          _transfer(_msgSender(), recipient, amount);
                          return true;
                      }
                      /**
                       * @dev See {BEP20-allowance}.
                       */
                      function allowance(address owner, address spender) public override view returns (uint256) {
                          return _allowances[owner][spender];
                      }
                      /**
                       * @dev See {BEP20-approve}.
                       *
                       * Requirements:
                       *
                       * - `spender` cannot be the zero address.
                       */
                      function approve(address spender, uint256 amount) public override returns (bool) {
                          _approve(_msgSender(), spender, amount);
                          return true;
                      }
                      /**
                       * @dev See {BEP20-transferFrom}.
                       *
                       * Emits an {Approval} event indicating the updated allowance. This is not
                       * required by the EIP. See the note at the beginning of {BEP20};
                       *
                       * 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 override returns (bool) {
                          _transfer(sender, recipient, amount);
                          _approve(
                              sender,
                              _msgSender(),
                              _allowances[sender][_msgSender()].sub(amount, 'BEP20: transfer amount 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 {BEP20-approve}.
                       *
                       * Emits an {Approval} event indicating the updated allowance.
                       *
                       * Requirements:
                       *
                       * - `spender` cannot be the zero address.
                       */
                      function increaseAllowance(address spender, uint256 addedValue) public returns (bool) {
                          _approve(_msgSender(), spender, _allowances[_msgSender()][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 {BEP20-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 returns (bool) {
                          _approve(
                              _msgSender(),
                              spender,
                              _allowances[_msgSender()][spender].sub(subtractedValue, 'BEP20: decreased allowance below zero')
                          );
                          return true;
                      }
                      /**
                       * @dev Creates `amount` tokens and assigns them to `msg.sender`, increasing
                       * the total supply.
                       *
                       * Requirements
                       *
                       * - `msg.sender` must be the token owner
                       */
                      function mint(uint256 amount) public onlyOwner returns (bool) {
                          _mint(_msgSender(), amount);
                          return true;
                      }
                      /**
                       * @dev Destroys `amount` tokens from `msg.sender`, decreasing the total supply.
                       *
                       */
                      function burn(uint256 amount) public returns (bool) {
                          _burn(_msgSender(), amount);
                          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), 'BEP20: transfer from the zero address');
                          require(recipient != address(0), 'BEP20: transfer to the zero address');
                          _balances[sender] = _balances[sender].sub(amount, 'BEP20: transfer amount 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 {
                          require(account != address(0), 'BEP20: mint to the zero address');
                          _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 {
                          require(account != address(0), 'BEP20: burn from the zero address');
                          _balances[account] = _balances[account].sub(amount, 'BEP20: burn amount exceeds balance');
                          _totalSupply = _totalSupply.sub(amount);
                          emit Transfer(account, address(0), amount);
                      }
                      /**
                       * @dev Sets `amount` as the allowance of `spender` over the `owner`s tokens.
                       *
                       * This is 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 {
                          require(owner != address(0), 'BEP20: approve from the zero address');
                          require(spender != address(0), 'BEP20: approve to the zero address');
                          _allowances[owner][spender] = amount;
                          emit Approval(owner, spender, amount);
                      }
                      /**
                       * @dev Destroys `amount` tokens from `account`.`amount` is then deducted
                       * from the caller's allowance.
                       *
                       * See {_burn} and {_approve}.
                       */
                      function _burnFrom(address account, uint256 amount) internal {
                          _burn(account, amount);
                          _approve(
                              account,
                              _msgSender(),
                              _allowances[account][_msgSender()].sub(amount, 'BEP20: burn amount exceeds allowance')
                          );
                      }
                  }
                  // SPDX-License-Identifier: GPL-3.0-or-later
                  pragma solidity >=0.4.0;
                  interface IBEP20 {
                      /**
                       * @dev Returns the amount of tokens in existence.
                       */
                      function totalSupply() external view returns (uint256);
                      /**
                       * @dev Returns the token decimals.
                       */
                      function decimals() external view returns (uint8);
                      /**
                       * @dev Returns the token symbol.
                       */
                      function symbol() external view returns (string memory);
                      /**
                       * @dev Returns the token name.
                       */
                      function name() external view returns (string memory);
                      /**
                       * @dev Returns the bep token owner.
                       */
                      function getOwner() external view returns (address);
                      /**
                       * @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: MIT
                  pragma solidity ^0.6.0;
                  import './IBEP20.sol';
                  import '../../math/SafeMath.sol';
                  import '../../utils/Address.sol';
                  /**
                   * @title SafeBEP20
                   * @dev Wrappers around BEP20 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 SafeBEP20 for IBEP20;` statement to your contract,
                   * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
                   */
                  library SafeBEP20 {
                      using SafeMath for uint256;
                      using Address for address;
                      function safeTransfer(
                          IBEP20 token,
                          address to,
                          uint256 value
                      ) internal {
                          _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
                      }
                      function safeTransferFrom(
                          IBEP20 token,
                          address from,
                          address to,
                          uint256 value
                      ) internal {
                          _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
                      }
                      /**
                       * @dev Deprecated. This function has issues similar to the ones found in
                       * {IBEP20-approve}, and its usage is discouraged.
                       *
                       * Whenever possible, use {safeIncreaseAllowance} and
                       * {safeDecreaseAllowance} instead.
                       */
                      function safeApprove(
                          IBEP20 token,
                          address spender,
                          uint256 value
                      ) internal {
                          // safeApprove should only be called when setting an initial allowance,
                          // or when resetting it to zero. To increase and decrease it, use
                          // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
                          // solhint-disable-next-line max-line-length
                          require(
                              (value == 0) || (token.allowance(address(this), spender) == 0),
                              'SafeBEP20: approve from non-zero to non-zero allowance'
                          );
                          _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
                      }
                      function safeIncreaseAllowance(
                          IBEP20 token,
                          address spender,
                          uint256 value
                      ) internal {
                          uint256 newAllowance = token.allowance(address(this), spender).add(value);
                          _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
                      }
                      function safeDecreaseAllowance(
                          IBEP20 token,
                          address spender,
                          uint256 value
                      ) internal {
                          uint256 newAllowance = token.allowance(address(this), spender).sub(
                              value,
                              'SafeBEP20: decreased allowance below zero'
                          );
                          _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
                      }
                      /**
                       * @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).
                       * @param token The token targeted by the call.
                       * @param data The call data (encoded using abi.encode or one of its variants).
                       */
                      function _callOptionalReturn(IBEP20 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. We use {Address.functionCall} to perform this call, which verifies that
                          // the target address contains contract code and also asserts for success in the low-level call.
                          bytes memory returndata = address(token).functionCall(data, 'SafeBEP20: low-level call failed');
                          if (returndata.length > 0) {
                              // Return data is optional
                              // solhint-disable-next-line max-line-length
                              require(abi.decode(returndata, (bool)), 'SafeBEP20: BEP20 operation did not succeed');
                          }
                      }
                  }
                  pragma solidity >=0.5.0;
                  interface ISphynxPair {
                      event Approval(address indexed owner, address indexed spender, uint value);
                      event Transfer(address indexed from, address indexed to, uint value);
                      function name() external pure returns (string memory);
                      function symbol() external pure returns (string memory);
                      function decimals() external pure returns (uint8);
                      function totalSupply() external view returns (uint);
                      function balanceOf(address owner) external view returns (uint);
                      function allowance(address owner, address spender) external view returns (uint);
                      function approve(address spender, uint value) external returns (bool);
                      function transfer(address to, uint value) external returns (bool);
                      function transferFrom(address from, address to, uint value) external returns (bool);
                      function DOMAIN_SEPARATOR() external view returns (bytes32);
                      function PERMIT_TYPEHASH() external pure returns (bytes32);
                      function nonces(address owner) external view returns (uint);
                      function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external;
                      event Mint(address indexed sender, uint amount0, uint amount1);
                      event Burn(address indexed sender, uint amount0, uint amount1, address indexed to);
                      event Swap(
                          address indexed sender,
                          uint amount0In,
                          uint amount1In,
                          uint amount0Out,
                          uint amount1Out,
                          address indexed to
                      );
                      event Sync(uint112 reserve0, uint112 reserve1);
                      function MINIMUM_LIQUIDITY() external pure returns (uint);
                      function factory() external view returns (address);
                      function token0() external view returns (address);
                      function token1() external view returns (address);
                      function getReserves() external view returns (uint112 reserve0, uint112 reserve1, uint32 blockTimestampLast);
                      function price0CumulativeLast() external view returns (uint);
                      function price1CumulativeLast() external view returns (uint);
                      function kLast() external view returns (uint);
                      function swapFee() external view returns (uint32);
                      function mint(address to) external returns (uint liquidity);
                      function burn(address to) external returns (uint amount0, uint amount1);
                      function swap(uint amount0Out, uint amount1Out, address to, bytes calldata data) external;
                      function skim(address to) external;
                      function sync() external;
                      function initialize(address, address) external;
                      function setSwapFee(uint32) external;
                  }
                  pragma solidity >=0.5.0;
                  interface ISphynxFactory {
                      event PairCreated(address indexed token0, address indexed token1, address pair, uint);
                      function feeTo() external view returns (address);
                      function feeToSetter() external view returns (address);
                      function getPair(address tokenA, address tokenB) external view returns (address pair);
                      function allPairs(uint) external view returns (address pair);
                      function allPairsLength() external view returns (uint);
                      function createPair(address tokenA, address tokenB) external returns (address pair);
                      function setFeeTo(address) external;
                      function setFeeToSetter(address) external;
                      function setSwapFee(address _pair, uint32 _swapFee) external;
                  }
                  pragma solidity >=0.6.2;
                  import './ISphynxRouter01.sol';
                  interface ISphynxRouter02 is ISphynxRouter01 {
                      function removeLiquidityETHSupportingFeeOnTransferTokens(
                          address token,
                          uint liquidity,
                          uint amountTokenMin,
                          uint amountETHMin,
                          address to,
                          uint deadline
                      ) external returns (uint amountETH);
                      function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
                          address token,
                          uint liquidity,
                          uint amountTokenMin,
                          uint amountETHMin,
                          address to,
                          uint deadline,
                          bool approveMax, uint8 v, bytes32 r, bytes32 s
                      ) external returns (uint amountETH);
                      function swapExactTokensForTokensSupportingFeeOnTransferTokens(
                          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 swapExactTokensForETHSupportingFeeOnTransferTokens(
                          uint amountIn,
                          uint amountOutMin,
                          address[] calldata path,
                          address to,
                          uint deadline
                      ) external;
                  }
                  // SPDX-License-Identifier: GPL-3.0-or-later
                  pragma solidity >=0.4.0;
                  /*
                   * @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 GSN 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.
                   */
                  contract Context {
                      // Empty internal constructor, to prevent people from mistakenly deploying
                      // an instance of this contract, which should be used via inheritance.
                      constructor() internal {}
                      function _msgSender() internal view returns (address payable) {
                          return msg.sender;
                      }
                      function _msgData() internal view returns (bytes memory) {
                          this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
                          return msg.data;
                      }
                  }
                  // SPDX-License-Identifier: GPL-3.0-or-later
                  pragma solidity >=0.4.0;
                  import '../GSN/Context.sol';
                  /**
                   * @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.
                   */
                  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() internal {
                          address msgSender = _msgSender();
                          _owner = msgSender;
                          emit OwnershipTransferred(address(0), msgSender);
                      }
                      /**
                       * @dev Returns the address of the current owner.
                       */
                      function owner() public view returns (address) {
                          return _owner;
                      }
                      /**
                       * @dev Throws if called by any account other than the owner.
                       */
                      modifier onlyOwner() {
                          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 onlyOwner {
                          emit OwnershipTransferred(_owner, address(0));
                          _owner = 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 onlyOwner {
                          _transferOwnership(newOwner);
                      }
                      /**
                       * @dev Transfers ownership of the contract to a new account (`newOwner`).
                       */
                      function _transferOwnership(address newOwner) internal {
                          require(newOwner != address(0), 'Ownable: new owner is the zero address');
                          emit OwnershipTransferred(_owner, newOwner);
                          _owner = newOwner;
                      }
                  }
                  // SPDX-License-Identifier: MIT
                  pragma solidity >=0.4.0;
                  /**
                   * @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, 'SafeMath: addition 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, 'SafeMath: subtraction 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,
                          string memory errorMessage
                      ) internal pure returns (uint256) {
                          require(b <= a, errorMessage);
                          uint256 c = a - b;
                          return c;
                      }
                      /**
                       * @dev Returns the multiplication of two unsigned integers, reverting on
                       * overflow.
                       *
                       * Counterpart to Solidity's `*` operator.
                       *
                       * Requirements:
                       *
                       * - Multiplication cannot overflow.
                       */
                      function mul(uint256 a, uint256 b) internal pure returns (uint256) {
                          // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
                          // benefit is lost if 'b' is also tested.
                          // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
                          if (a == 0) {
                              return 0;
                          }
                          uint256 c = a * b;
                          require(c / a == b, 'SafeMath: multiplication overflow');
                          return c;
                      }
                      /**
                       * @dev Returns the integer division of two unsigned integers. Reverts on
                       * division by zero. The result is rounded towards zero.
                       *
                       * Counterpart to Solidity's `/` operator. Note: this function uses a
                       * `revert` opcode (which leaves remaining gas untouched) while Solidity
                       * uses an invalid opcode to revert (consuming all remaining gas).
                       *
                       * Requirements:
                       *
                       * - The divisor cannot be zero.
                       */
                      function div(uint256 a, uint256 b) internal pure returns (uint256) {
                          return div(a, b, 'SafeMath: division by zero');
                      }
                      /**
                       * @dev Returns the integer division of two unsigned integers. Reverts with custom message on
                       * division by zero. The result is rounded towards zero.
                       *
                       * Counterpart to Solidity's `/` operator. Note: this function uses a
                       * `revert` opcode (which leaves remaining gas untouched) while Solidity
                       * uses an invalid opcode to revert (consuming all remaining gas).
                       *
                       * Requirements:
                       *
                       * - The divisor cannot be zero.
                       */
                      function div(
                          uint256 a,
                          uint256 b,
                          string memory errorMessage
                      ) internal pure returns (uint256) {
                          require(b > 0, errorMessage);
                          uint256 c = a / b;
                          // assert(a == b * c + a % b); // There is no case in which this doesn't hold
                          return c;
                      }
                      /**
                       * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
                       * Reverts when dividing by zero.
                       *
                       * Counterpart to Solidity's `%` operator. This function uses a `revert`
                       * opcode (which leaves remaining gas untouched) while Solidity uses an
                       * invalid opcode to revert (consuming all remaining gas).
                       *
                       * Requirements:
                       *
                       * - The divisor cannot be zero.
                       */
                      function mod(uint256 a, uint256 b) internal pure returns (uint256) {
                          return mod(a, b, 'SafeMath: modulo by zero');
                      }
                      /**
                       * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
                       * Reverts with custom message when dividing by zero.
                       *
                       * Counterpart to Solidity's `%` operator. This function uses a `revert`
                       * opcode (which leaves remaining gas untouched) while Solidity uses an
                       * invalid opcode to revert (consuming all remaining gas).
                       *
                       * Requirements:
                       *
                       * - The divisor cannot be zero.
                       */
                      function mod(
                          uint256 a,
                          uint256 b,
                          string memory errorMessage
                      ) internal pure returns (uint256) {
                          require(b != 0, errorMessage);
                          return a % b;
                      }
                      function min(uint256 x, uint256 y) internal pure returns (uint256 z) {
                          z = x < y ? x : y;
                      }
                      // babylonian method (https://en.wikipedia.org/wiki/Methods_of_computing_square_roots#Babylonian_method)
                      function sqrt(uint256 y) internal pure returns (uint256 z) {
                          if (y > 3) {
                              z = y;
                              uint256 x = y / 2 + 1;
                              while (x < z) {
                                  z = x;
                                  x = (y / x + x) / 2;
                              }
                          } else if (y != 0) {
                              z = 1;
                          }
                      }
                  }
                  // SPDX-License-Identifier: MIT
                  pragma solidity ^0.6.2;
                  /**
                   * @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) {
                          // According to EIP-1052, 0x0 is the value returned for not-yet created accounts
                          // and 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470 is returned
                          // for accounts without code, i.e. `keccak256('')`
                          bytes32 codehash;
                          bytes32 accountHash = 0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470;
                          // solhint-disable-next-line no-inline-assembly
                          assembly {
                              codehash := extcodehash(account)
                          }
                          return (codehash != accountHash && codehash != 0x0);
                      }
                      /**
                       * @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');
                          // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
                          (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');
                          return _functionCallWithValue(target, data, value, errorMessage);
                      }
                      function _functionCallWithValue(
                          address target,
                          bytes memory data,
                          uint256 weiValue,
                          string memory errorMessage
                      ) private returns (bytes memory) {
                          require(isContract(target), 'Address: call to non-contract');
                          // solhint-disable-next-line avoid-low-level-calls
                          (bool success, bytes memory returndata) = target.call{value: weiValue}(data);
                          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
                                  // solhint-disable-next-line no-inline-assembly
                                  assembly {
                                      let returndata_size := mload(returndata)
                                      revert(add(32, returndata), returndata_size)
                                  }
                              } else {
                                  revert(errorMessage);
                              }
                          }
                      }
                  }
                  pragma solidity >=0.6.2;
                  interface ISphynxRouter01 {
                      function factory() external pure returns (address);
                      function WETH() external pure returns (address);
                      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 addLiquidityETH(
                          address token,
                          uint amountTokenDesired,
                          uint amountTokenMin,
                          uint amountETHMin,
                          address to,
                          uint deadline
                      ) external payable returns (uint amountToken, uint amountETH, uint liquidity);
                      function removeLiquidity(
                          address tokenA,
                          address tokenB,
                          uint liquidity,
                          uint amountAMin,
                          uint amountBMin,
                          address to,
                          uint deadline
                      ) external returns (uint amountA, uint amountB);
                      function removeLiquidityETH(
                          address token,
                          uint liquidity,
                          uint amountTokenMin,
                          uint amountETHMin,
                          address to,
                          uint deadline
                      ) external returns (uint amountToken, uint amountETH);
                      function removeLiquidityWithPermit(
                          address tokenA,
                          address tokenB,
                          uint liquidity,
                          uint amountAMin,
                          uint amountBMin,
                          address to,
                          uint deadline,
                          bool approveMax, uint8 v, bytes32 r, bytes32 s
                      ) external returns (uint amountA, uint amountB);
                      function removeLiquidityETHWithPermit(
                          address token,
                          uint liquidity,
                          uint amountTokenMin,
                          uint amountETHMin,
                          address to,
                          uint deadline,
                          bool approveMax, uint8 v, bytes32 r, bytes32 s
                      ) external returns (uint amountToken, uint amountETH);
                      function swapExactTokensForTokens(
                          uint amountIn,
                          uint amountOutMin,
                          address[] calldata path,
                          address to,
                          uint deadline
                      ) external returns (uint[] memory amounts);
                      function swapTokensForExactTokens(
                          uint amountOut,
                          uint amountInMax,
                          address[] calldata path,
                          address to,
                          uint deadline
                      ) external returns (uint[] memory amounts);
                      function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline)
                          external
                          payable
                          returns (uint[] memory amounts);
                      function swapTokensForExactETH(uint amountOut, uint amountInMax, address[] calldata path, address to, uint deadline)
                          external
                          returns (uint[] memory amounts);
                      function swapExactTokensForETH(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline)
                          external
                          returns (uint[] memory amounts);
                      function swapETHForExactTokens(uint amountOut, address[] calldata path, address to, uint deadline)
                          external
                          payable
                          returns (uint[] memory amounts);
                      function quote(uint amountA, uint reserveA, uint reserveB) external pure returns (uint amountB);
                      function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut, uint swapFee) external pure returns (uint amountOut);
                      function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut, uint swapFee) external pure returns (uint amountIn);
                      function getAmountsOut(uint amountIn, address[] calldata path) external view returns (uint[] memory amounts);
                      function getAmountsIn(uint amountOut, address[] calldata path) external view returns (uint[] memory amounts);
                  }
                  

                  File 3 of 7: UniswapV2Pair
                  // File: contracts/interfaces/IUniswapV2Pair.sol
                  
                  pragma solidity >=0.5.0;
                  
                  interface IUniswapV2Pair {
                      event Approval(address indexed owner, address indexed spender, uint value);
                      event Transfer(address indexed from, address indexed to, uint value);
                  
                      function name() external pure returns (string memory);
                      function symbol() external pure returns (string memory);
                      function decimals() external pure returns (uint8);
                      function totalSupply() external view returns (uint);
                      function balanceOf(address owner) external view returns (uint);
                      function allowance(address owner, address spender) external view returns (uint);
                  
                      function approve(address spender, uint value) external returns (bool);
                      function transfer(address to, uint value) external returns (bool);
                      function transferFrom(address from, address to, uint value) external returns (bool);
                  
                      function DOMAIN_SEPARATOR() external view returns (bytes32);
                      function PERMIT_TYPEHASH() external pure returns (bytes32);
                      function nonces(address owner) external view returns (uint);
                  
                      function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external;
                  
                      event Mint(address indexed sender, uint amount0, uint amount1);
                      event Burn(address indexed sender, uint amount0, uint amount1, address indexed to);
                      event Swap(
                          address indexed sender,
                          uint amount0In,
                          uint amount1In,
                          uint amount0Out,
                          uint amount1Out,
                          address indexed to
                      );
                      event Sync(uint112 reserve0, uint112 reserve1);
                  
                      function MINIMUM_LIQUIDITY() external pure returns (uint);
                      function factory() external view returns (address);
                      function token0() external view returns (address);
                      function token1() external view returns (address);
                      function getReserves() external view returns (uint112 reserve0, uint112 reserve1, uint32 blockTimestampLast);
                      function price0CumulativeLast() external view returns (uint);
                      function price1CumulativeLast() external view returns (uint);
                      function kLast() external view returns (uint);
                  
                      function mint(address to) external returns (uint liquidity);
                      function burn(address to) external returns (uint amount0, uint amount1);
                      function swap(uint amount0Out, uint amount1Out, address to, bytes calldata data) external;
                      function skim(address to) external;
                      function sync() external;
                  
                      function initialize(address, address) external;
                  }
                  
                  // File: contracts/interfaces/IUniswapV2ERC20.sol
                  
                  pragma solidity >=0.5.0;
                  
                  interface IUniswapV2ERC20 {
                      event Approval(address indexed owner, address indexed spender, uint value);
                      event Transfer(address indexed from, address indexed to, uint value);
                  
                      function name() external pure returns (string memory);
                      function symbol() external pure returns (string memory);
                      function decimals() external pure returns (uint8);
                      function totalSupply() external view returns (uint);
                      function balanceOf(address owner) external view returns (uint);
                      function allowance(address owner, address spender) external view returns (uint);
                  
                      function approve(address spender, uint value) external returns (bool);
                      function transfer(address to, uint value) external returns (bool);
                      function transferFrom(address from, address to, uint value) external returns (bool);
                  
                      function DOMAIN_SEPARATOR() external view returns (bytes32);
                      function PERMIT_TYPEHASH() external pure returns (bytes32);
                      function nonces(address owner) external view returns (uint);
                  
                      function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external;
                  }
                  
                  // File: contracts/libraries/SafeMath.sol
                  
                  pragma solidity =0.5.16;
                  
                  // a library for performing overflow-safe math, courtesy of DappHub (https://github.com/dapphub/ds-math)
                  
                  library SafeMath {
                      function add(uint x, uint y) internal pure returns (uint z) {
                          require((z = x + y) >= x, 'ds-math-add-overflow');
                      }
                  
                      function sub(uint x, uint y) internal pure returns (uint z) {
                          require((z = x - y) <= x, 'ds-math-sub-underflow');
                      }
                  
                      function mul(uint x, uint y) internal pure returns (uint z) {
                          require(y == 0 || (z = x * y) / y == x, 'ds-math-mul-overflow');
                      }
                  }
                  
                  // File: contracts/UniswapV2ERC20.sol
                  
                  pragma solidity =0.5.16;
                  
                  
                  
                  contract UniswapV2ERC20 is IUniswapV2ERC20 {
                      using SafeMath for uint;
                  
                      string public constant name = 'Uniswap V2';
                      string public constant symbol = 'UNI-V2';
                      uint8 public constant decimals = 18;
                      uint  public totalSupply;
                      mapping(address => uint) public balanceOf;
                      mapping(address => mapping(address => uint)) public allowance;
                  
                      bytes32 public DOMAIN_SEPARATOR;
                      // keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)");
                      bytes32 public constant PERMIT_TYPEHASH = 0x6e71edae12b1b97f4d1f60370fef10105fa2faae0126114a169c64845d6126c9;
                      mapping(address => uint) public nonces;
                  
                      event Approval(address indexed owner, address indexed spender, uint value);
                      event Transfer(address indexed from, address indexed to, uint value);
                  
                      constructor() public {
                          uint chainId;
                          assembly {
                              chainId := chainid
                          }
                          DOMAIN_SEPARATOR = keccak256(
                              abi.encode(
                                  keccak256('EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)'),
                                  keccak256(bytes(name)),
                                  keccak256(bytes('1')),
                                  chainId,
                                  address(this)
                              )
                          );
                      }
                  
                      function _mint(address to, uint value) internal {
                          totalSupply = totalSupply.add(value);
                          balanceOf[to] = balanceOf[to].add(value);
                          emit Transfer(address(0), to, value);
                      }
                  
                      function _burn(address from, uint value) internal {
                          balanceOf[from] = balanceOf[from].sub(value);
                          totalSupply = totalSupply.sub(value);
                          emit Transfer(from, address(0), value);
                      }
                  
                      function _approve(address owner, address spender, uint value) private {
                          allowance[owner][spender] = value;
                          emit Approval(owner, spender, value);
                      }
                  
                      function _transfer(address from, address to, uint value) private {
                          balanceOf[from] = balanceOf[from].sub(value);
                          balanceOf[to] = balanceOf[to].add(value);
                          emit Transfer(from, to, value);
                      }
                  
                      function approve(address spender, uint value) external returns (bool) {
                          _approve(msg.sender, spender, value);
                          return true;
                      }
                  
                      function transfer(address to, uint value) external returns (bool) {
                          _transfer(msg.sender, to, value);
                          return true;
                      }
                  
                      function transferFrom(address from, address to, uint value) external returns (bool) {
                          if (allowance[from][msg.sender] != uint(-1)) {
                              allowance[from][msg.sender] = allowance[from][msg.sender].sub(value);
                          }
                          _transfer(from, to, value);
                          return true;
                      }
                  
                      function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external {
                          require(deadline >= block.timestamp, 'UniswapV2: EXPIRED');
                          bytes32 digest = keccak256(
                              abi.encodePacked(
                                  '\x19\x01',
                                  DOMAIN_SEPARATOR,
                                  keccak256(abi.encode(PERMIT_TYPEHASH, owner, spender, value, nonces[owner]++, deadline))
                              )
                          );
                          address recoveredAddress = ecrecover(digest, v, r, s);
                          require(recoveredAddress != address(0) && recoveredAddress == owner, 'UniswapV2: INVALID_SIGNATURE');
                          _approve(owner, spender, value);
                      }
                  }
                  
                  // File: contracts/libraries/Math.sol
                  
                  pragma solidity =0.5.16;
                  
                  // a library for performing various math operations
                  
                  library Math {
                      function min(uint x, uint y) internal pure returns (uint z) {
                          z = x < y ? x : y;
                      }
                  
                      // babylonian method (https://en.wikipedia.org/wiki/Methods_of_computing_square_roots#Babylonian_method)
                      function sqrt(uint y) internal pure returns (uint z) {
                          if (y > 3) {
                              z = y;
                              uint x = y / 2 + 1;
                              while (x < z) {
                                  z = x;
                                  x = (y / x + x) / 2;
                              }
                          } else if (y != 0) {
                              z = 1;
                          }
                      }
                  }
                  
                  // File: contracts/libraries/UQ112x112.sol
                  
                  pragma solidity =0.5.16;
                  
                  // a library for handling binary fixed point numbers (https://en.wikipedia.org/wiki/Q_(number_format))
                  
                  // range: [0, 2**112 - 1]
                  // resolution: 1 / 2**112
                  
                  library UQ112x112 {
                      uint224 constant Q112 = 2**112;
                  
                      // encode a uint112 as a UQ112x112
                      function encode(uint112 y) internal pure returns (uint224 z) {
                          z = uint224(y) * Q112; // never overflows
                      }
                  
                      // divide a UQ112x112 by a uint112, returning a UQ112x112
                      function uqdiv(uint224 x, uint112 y) internal pure returns (uint224 z) {
                          z = x / uint224(y);
                      }
                  }
                  
                  // File: contracts/interfaces/IERC20.sol
                  
                  pragma solidity >=0.5.0;
                  
                  interface IERC20 {
                      event Approval(address indexed owner, address indexed spender, uint value);
                      event Transfer(address indexed from, address indexed to, uint value);
                  
                      function name() external view returns (string memory);
                      function symbol() external view returns (string memory);
                      function decimals() external view returns (uint8);
                      function totalSupply() external view returns (uint);
                      function balanceOf(address owner) external view returns (uint);
                      function allowance(address owner, address spender) external view returns (uint);
                  
                      function approve(address spender, uint value) external returns (bool);
                      function transfer(address to, uint value) external returns (bool);
                      function transferFrom(address from, address to, uint value) external returns (bool);
                  }
                  
                  // File: contracts/interfaces/IUniswapV2Factory.sol
                  
                  pragma solidity >=0.5.0;
                  
                  interface IUniswapV2Factory {
                      event PairCreated(address indexed token0, address indexed token1, address pair, uint);
                  
                      function feeTo() external view returns (address);
                      function feeToSetter() external view returns (address);
                  
                      function getPair(address tokenA, address tokenB) external view returns (address pair);
                      function allPairs(uint) external view returns (address pair);
                      function allPairsLength() external view returns (uint);
                  
                      function createPair(address tokenA, address tokenB) external returns (address pair);
                  
                      function setFeeTo(address) external;
                      function setFeeToSetter(address) external;
                  }
                  
                  // File: contracts/interfaces/IUniswapV2Callee.sol
                  
                  pragma solidity >=0.5.0;
                  
                  interface IUniswapV2Callee {
                      function uniswapV2Call(address sender, uint amount0, uint amount1, bytes calldata data) external;
                  }
                  
                  // File: contracts/UniswapV2Pair.sol
                  
                  pragma solidity =0.5.16;
                  
                  
                  
                  
                  
                  
                  
                  
                  contract UniswapV2Pair is IUniswapV2Pair, UniswapV2ERC20 {
                      using SafeMath  for uint;
                      using UQ112x112 for uint224;
                  
                      uint public constant MINIMUM_LIQUIDITY = 10**3;
                      bytes4 private constant SELECTOR = bytes4(keccak256(bytes('transfer(address,uint256)')));
                  
                      address public factory;
                      address public token0;
                      address public token1;
                  
                      uint112 private reserve0;           // uses single storage slot, accessible via getReserves
                      uint112 private reserve1;           // uses single storage slot, accessible via getReserves
                      uint32  private blockTimestampLast; // uses single storage slot, accessible via getReserves
                  
                      uint public price0CumulativeLast;
                      uint public price1CumulativeLast;
                      uint public kLast; // reserve0 * reserve1, as of immediately after the most recent liquidity event
                  
                      uint private unlocked = 1;
                      modifier lock() {
                          require(unlocked == 1, 'UniswapV2: LOCKED');
                          unlocked = 0;
                          _;
                          unlocked = 1;
                      }
                  
                      function getReserves() public view returns (uint112 _reserve0, uint112 _reserve1, uint32 _blockTimestampLast) {
                          _reserve0 = reserve0;
                          _reserve1 = reserve1;
                          _blockTimestampLast = blockTimestampLast;
                      }
                  
                      function _safeTransfer(address token, address to, uint value) private {
                          (bool success, bytes memory data) = token.call(abi.encodeWithSelector(SELECTOR, to, value));
                          require(success && (data.length == 0 || abi.decode(data, (bool))), 'UniswapV2: TRANSFER_FAILED');
                      }
                  
                      event Mint(address indexed sender, uint amount0, uint amount1);
                      event Burn(address indexed sender, uint amount0, uint amount1, address indexed to);
                      event Swap(
                          address indexed sender,
                          uint amount0In,
                          uint amount1In,
                          uint amount0Out,
                          uint amount1Out,
                          address indexed to
                      );
                      event Sync(uint112 reserve0, uint112 reserve1);
                  
                      constructor() public {
                          factory = msg.sender;
                      }
                  
                      // called once by the factory at time of deployment
                      function initialize(address _token0, address _token1) external {
                          require(msg.sender == factory, 'UniswapV2: FORBIDDEN'); // sufficient check
                          token0 = _token0;
                          token1 = _token1;
                      }
                  
                      // update reserves and, on the first call per block, price accumulators
                      function _update(uint balance0, uint balance1, uint112 _reserve0, uint112 _reserve1) private {
                          require(balance0 <= uint112(-1) && balance1 <= uint112(-1), 'UniswapV2: OVERFLOW');
                          uint32 blockTimestamp = uint32(block.timestamp % 2**32);
                          uint32 timeElapsed = blockTimestamp - blockTimestampLast; // overflow is desired
                          if (timeElapsed > 0 && _reserve0 != 0 && _reserve1 != 0) {
                              // * never overflows, and + overflow is desired
                              price0CumulativeLast += uint(UQ112x112.encode(_reserve1).uqdiv(_reserve0)) * timeElapsed;
                              price1CumulativeLast += uint(UQ112x112.encode(_reserve0).uqdiv(_reserve1)) * timeElapsed;
                          }
                          reserve0 = uint112(balance0);
                          reserve1 = uint112(balance1);
                          blockTimestampLast = blockTimestamp;
                          emit Sync(reserve0, reserve1);
                      }
                  
                      // if fee is on, mint liquidity equivalent to 1/6th of the growth in sqrt(k)
                      function _mintFee(uint112 _reserve0, uint112 _reserve1) private returns (bool feeOn) {
                          address feeTo = IUniswapV2Factory(factory).feeTo();
                          feeOn = feeTo != address(0);
                          uint _kLast = kLast; // gas savings
                          if (feeOn) {
                              if (_kLast != 0) {
                                  uint rootK = Math.sqrt(uint(_reserve0).mul(_reserve1));
                                  uint rootKLast = Math.sqrt(_kLast);
                                  if (rootK > rootKLast) {
                                      uint numerator = totalSupply.mul(rootK.sub(rootKLast));
                                      uint denominator = rootK.mul(5).add(rootKLast);
                                      uint liquidity = numerator / denominator;
                                      if (liquidity > 0) _mint(feeTo, liquidity);
                                  }
                              }
                          } else if (_kLast != 0) {
                              kLast = 0;
                          }
                      }
                  
                      // this low-level function should be called from a contract which performs important safety checks
                      function mint(address to) external lock returns (uint liquidity) {
                          (uint112 _reserve0, uint112 _reserve1,) = getReserves(); // gas savings
                          uint balance0 = IERC20(token0).balanceOf(address(this));
                          uint balance1 = IERC20(token1).balanceOf(address(this));
                          uint amount0 = balance0.sub(_reserve0);
                          uint amount1 = balance1.sub(_reserve1);
                  
                          bool feeOn = _mintFee(_reserve0, _reserve1);
                          uint _totalSupply = totalSupply; // gas savings, must be defined here since totalSupply can update in _mintFee
                          if (_totalSupply == 0) {
                              liquidity = Math.sqrt(amount0.mul(amount1)).sub(MINIMUM_LIQUIDITY);
                             _mint(address(0), MINIMUM_LIQUIDITY); // permanently lock the first MINIMUM_LIQUIDITY tokens
                          } else {
                              liquidity = Math.min(amount0.mul(_totalSupply) / _reserve0, amount1.mul(_totalSupply) / _reserve1);
                          }
                          require(liquidity > 0, 'UniswapV2: INSUFFICIENT_LIQUIDITY_MINTED');
                          _mint(to, liquidity);
                  
                          _update(balance0, balance1, _reserve0, _reserve1);
                          if (feeOn) kLast = uint(reserve0).mul(reserve1); // reserve0 and reserve1 are up-to-date
                          emit Mint(msg.sender, amount0, amount1);
                      }
                  
                      // this low-level function should be called from a contract which performs important safety checks
                      function burn(address to) external lock returns (uint amount0, uint amount1) {
                          (uint112 _reserve0, uint112 _reserve1,) = getReserves(); // gas savings
                          address _token0 = token0;                                // gas savings
                          address _token1 = token1;                                // gas savings
                          uint balance0 = IERC20(_token0).balanceOf(address(this));
                          uint balance1 = IERC20(_token1).balanceOf(address(this));
                          uint liquidity = balanceOf[address(this)];
                  
                          bool feeOn = _mintFee(_reserve0, _reserve1);
                          uint _totalSupply = totalSupply; // gas savings, must be defined here since totalSupply can update in _mintFee
                          amount0 = liquidity.mul(balance0) / _totalSupply; // using balances ensures pro-rata distribution
                          amount1 = liquidity.mul(balance1) / _totalSupply; // using balances ensures pro-rata distribution
                          require(amount0 > 0 && amount1 > 0, 'UniswapV2: INSUFFICIENT_LIQUIDITY_BURNED');
                          _burn(address(this), liquidity);
                          _safeTransfer(_token0, to, amount0);
                          _safeTransfer(_token1, to, amount1);
                          balance0 = IERC20(_token0).balanceOf(address(this));
                          balance1 = IERC20(_token1).balanceOf(address(this));
                  
                          _update(balance0, balance1, _reserve0, _reserve1);
                          if (feeOn) kLast = uint(reserve0).mul(reserve1); // reserve0 and reserve1 are up-to-date
                          emit Burn(msg.sender, amount0, amount1, to);
                      }
                  
                      // this low-level function should be called from a contract which performs important safety checks
                      function swap(uint amount0Out, uint amount1Out, address to, bytes calldata data) external lock {
                          require(amount0Out > 0 || amount1Out > 0, 'UniswapV2: INSUFFICIENT_OUTPUT_AMOUNT');
                          (uint112 _reserve0, uint112 _reserve1,) = getReserves(); // gas savings
                          require(amount0Out < _reserve0 && amount1Out < _reserve1, 'UniswapV2: INSUFFICIENT_LIQUIDITY');
                  
                          uint balance0;
                          uint balance1;
                          { // scope for _token{0,1}, avoids stack too deep errors
                          address _token0 = token0;
                          address _token1 = token1;
                          require(to != _token0 && to != _token1, 'UniswapV2: INVALID_TO');
                          if (amount0Out > 0) _safeTransfer(_token0, to, amount0Out); // optimistically transfer tokens
                          if (amount1Out > 0) _safeTransfer(_token1, to, amount1Out); // optimistically transfer tokens
                          if (data.length > 0) IUniswapV2Callee(to).uniswapV2Call(msg.sender, amount0Out, amount1Out, data);
                          balance0 = IERC20(_token0).balanceOf(address(this));
                          balance1 = IERC20(_token1).balanceOf(address(this));
                          }
                          uint amount0In = balance0 > _reserve0 - amount0Out ? balance0 - (_reserve0 - amount0Out) : 0;
                          uint amount1In = balance1 > _reserve1 - amount1Out ? balance1 - (_reserve1 - amount1Out) : 0;
                          require(amount0In > 0 || amount1In > 0, 'UniswapV2: INSUFFICIENT_INPUT_AMOUNT');
                          { // scope for reserve{0,1}Adjusted, avoids stack too deep errors
                          uint balance0Adjusted = balance0.mul(1000).sub(amount0In.mul(3));
                          uint balance1Adjusted = balance1.mul(1000).sub(amount1In.mul(3));
                          require(balance0Adjusted.mul(balance1Adjusted) >= uint(_reserve0).mul(_reserve1).mul(1000**2), 'UniswapV2: K');
                          }
                  
                          _update(balance0, balance1, _reserve0, _reserve1);
                          emit Swap(msg.sender, amount0In, amount1In, amount0Out, amount1Out, to);
                      }
                  
                      // force balances to match reserves
                      function skim(address to) external lock {
                          address _token0 = token0; // gas savings
                          address _token1 = token1; // gas savings
                          _safeTransfer(_token0, to, IERC20(_token0).balanceOf(address(this)).sub(reserve0));
                          _safeTransfer(_token1, to, IERC20(_token1).balanceOf(address(this)).sub(reserve1));
                      }
                  
                      // force reserves to match balances
                      function sync() external lock {
                          _update(IERC20(token0).balanceOf(address(this)), IERC20(token1).balanceOf(address(this)), reserve0, reserve1);
                      }
                  }

                  File 4 of 7: 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;
                      }
                  }
                  
                  
                  /*
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                                         Version 3, 29 June 2007
                  
                   Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
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                  File 5 of 7: UniswapV2Router02
                  pragma solidity =0.6.6;
                  
                  interface IUniswapV2Factory {
                      event PairCreated(address indexed token0, address indexed token1, address pair, uint);
                  
                      function feeTo() external view returns (address);
                      function feeToSetter() external view returns (address);
                  
                      function getPair(address tokenA, address tokenB) external view returns (address pair);
                      function allPairs(uint) external view returns (address pair);
                      function allPairsLength() external view returns (uint);
                  
                      function createPair(address tokenA, address tokenB) external returns (address pair);
                  
                      function setFeeTo(address) external;
                      function setFeeToSetter(address) external;
                  }
                  
                  interface IUniswapV2Pair {
                      event Approval(address indexed owner, address indexed spender, uint value);
                      event Transfer(address indexed from, address indexed to, uint value);
                  
                      function name() external pure returns (string memory);
                      function symbol() external pure returns (string memory);
                      function decimals() external pure returns (uint8);
                      function totalSupply() external view returns (uint);
                      function balanceOf(address owner) external view returns (uint);
                      function allowance(address owner, address spender) external view returns (uint);
                  
                      function approve(address spender, uint value) external returns (bool);
                      function transfer(address to, uint value) external returns (bool);
                      function transferFrom(address from, address to, uint value) external returns (bool);
                  
                      function DOMAIN_SEPARATOR() external view returns (bytes32);
                      function PERMIT_TYPEHASH() external pure returns (bytes32);
                      function nonces(address owner) external view returns (uint);
                  
                      function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external;
                  
                      event Mint(address indexed sender, uint amount0, uint amount1);
                      event Burn(address indexed sender, uint amount0, uint amount1, address indexed to);
                      event Swap(
                          address indexed sender,
                          uint amount0In,
                          uint amount1In,
                          uint amount0Out,
                          uint amount1Out,
                          address indexed to
                      );
                      event Sync(uint112 reserve0, uint112 reserve1);
                  
                      function MINIMUM_LIQUIDITY() external pure returns (uint);
                      function factory() external view returns (address);
                      function token0() external view returns (address);
                      function token1() external view returns (address);
                      function getReserves() external view returns (uint112 reserve0, uint112 reserve1, uint32 blockTimestampLast);
                      function price0CumulativeLast() external view returns (uint);
                      function price1CumulativeLast() external view returns (uint);
                      function kLast() external view returns (uint);
                  
                      function mint(address to) external returns (uint liquidity);
                      function burn(address to) external returns (uint amount0, uint amount1);
                      function swap(uint amount0Out, uint amount1Out, address to, bytes calldata data) external;
                      function skim(address to) external;
                      function sync() external;
                  
                      function initialize(address, address) external;
                  }
                  
                  interface IUniswapV2Router01 {
                      function factory() external pure returns (address);
                      function WETH() external pure returns (address);
                  
                      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 addLiquidityETH(
                          address token,
                          uint amountTokenDesired,
                          uint amountTokenMin,
                          uint amountETHMin,
                          address to,
                          uint deadline
                      ) external payable returns (uint amountToken, uint amountETH, uint liquidity);
                      function removeLiquidity(
                          address tokenA,
                          address tokenB,
                          uint liquidity,
                          uint amountAMin,
                          uint amountBMin,
                          address to,
                          uint deadline
                      ) external returns (uint amountA, uint amountB);
                      function removeLiquidityETH(
                          address token,
                          uint liquidity,
                          uint amountTokenMin,
                          uint amountETHMin,
                          address to,
                          uint deadline
                      ) external returns (uint amountToken, uint amountETH);
                      function removeLiquidityWithPermit(
                          address tokenA,
                          address tokenB,
                          uint liquidity,
                          uint amountAMin,
                          uint amountBMin,
                          address to,
                          uint deadline,
                          bool approveMax, uint8 v, bytes32 r, bytes32 s
                      ) external returns (uint amountA, uint amountB);
                      function removeLiquidityETHWithPermit(
                          address token,
                          uint liquidity,
                          uint amountTokenMin,
                          uint amountETHMin,
                          address to,
                          uint deadline,
                          bool approveMax, uint8 v, bytes32 r, bytes32 s
                      ) external returns (uint amountToken, uint amountETH);
                      function swapExactTokensForTokens(
                          uint amountIn,
                          uint amountOutMin,
                          address[] calldata path,
                          address to,
                          uint deadline
                      ) external returns (uint[] memory amounts);
                      function swapTokensForExactTokens(
                          uint amountOut,
                          uint amountInMax,
                          address[] calldata path,
                          address to,
                          uint deadline
                      ) external returns (uint[] memory amounts);
                      function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline)
                          external
                          payable
                          returns (uint[] memory amounts);
                      function swapTokensForExactETH(uint amountOut, uint amountInMax, address[] calldata path, address to, uint deadline)
                          external
                          returns (uint[] memory amounts);
                      function swapExactTokensForETH(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline)
                          external
                          returns (uint[] memory amounts);
                      function swapETHForExactTokens(uint amountOut, address[] calldata path, address to, uint deadline)
                          external
                          payable
                          returns (uint[] memory amounts);
                  
                      function quote(uint amountA, uint reserveA, uint reserveB) external pure returns (uint amountB);
                      function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut) external pure returns (uint amountOut);
                      function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut) external pure returns (uint amountIn);
                      function getAmountsOut(uint amountIn, address[] calldata path) external view returns (uint[] memory amounts);
                      function getAmountsIn(uint amountOut, address[] calldata path) external view returns (uint[] memory amounts);
                  }
                  
                  interface IUniswapV2Router02 is IUniswapV2Router01 {
                      function removeLiquidityETHSupportingFeeOnTransferTokens(
                          address token,
                          uint liquidity,
                          uint amountTokenMin,
                          uint amountETHMin,
                          address to,
                          uint deadline
                      ) external returns (uint amountETH);
                      function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
                          address token,
                          uint liquidity,
                          uint amountTokenMin,
                          uint amountETHMin,
                          address to,
                          uint deadline,
                          bool approveMax, uint8 v, bytes32 r, bytes32 s
                      ) external returns (uint amountETH);
                  
                      function swapExactTokensForTokensSupportingFeeOnTransferTokens(
                          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 swapExactTokensForETHSupportingFeeOnTransferTokens(
                          uint amountIn,
                          uint amountOutMin,
                          address[] calldata path,
                          address to,
                          uint deadline
                      ) external;
                  }
                  
                  interface IERC20 {
                      event Approval(address indexed owner, address indexed spender, uint value);
                      event Transfer(address indexed from, address indexed to, uint value);
                  
                      function name() external view returns (string memory);
                      function symbol() external view returns (string memory);
                      function decimals() external view returns (uint8);
                      function totalSupply() external view returns (uint);
                      function balanceOf(address owner) external view returns (uint);
                      function allowance(address owner, address spender) external view returns (uint);
                  
                      function approve(address spender, uint value) external returns (bool);
                      function transfer(address to, uint value) external returns (bool);
                      function transferFrom(address from, address to, uint value) external returns (bool);
                  }
                  
                  interface IWETH {
                      function deposit() external payable;
                      function transfer(address to, uint value) external returns (bool);
                      function withdraw(uint) external;
                  }
                  
                  contract UniswapV2Router02 is IUniswapV2Router02 {
                      using SafeMath for uint;
                  
                      address public immutable override factory;
                      address public immutable override WETH;
                  
                      modifier ensure(uint deadline) {
                          require(deadline >= block.timestamp, 'UniswapV2Router: EXPIRED');
                          _;
                      }
                  
                      constructor(address _factory, address _WETH) public {
                          factory = _factory;
                          WETH = _WETH;
                      }
                  
                      receive() external payable {
                          assert(msg.sender == WETH); // only accept ETH via fallback from the WETH contract
                      }
                  
                      // **** ADD LIQUIDITY ****
                      function _addLiquidity(
                          address tokenA,
                          address tokenB,
                          uint amountADesired,
                          uint amountBDesired,
                          uint amountAMin,
                          uint amountBMin
                      ) internal virtual returns (uint amountA, uint amountB) {
                          // create the pair if it doesn't exist yet
                          if (IUniswapV2Factory(factory).getPair(tokenA, tokenB) == address(0)) {
                              IUniswapV2Factory(factory).createPair(tokenA, tokenB);
                          }
                          (uint reserveA, uint reserveB) = UniswapV2Library.getReserves(factory, tokenA, tokenB);
                          if (reserveA == 0 && reserveB == 0) {
                              (amountA, amountB) = (amountADesired, amountBDesired);
                          } else {
                              uint amountBOptimal = UniswapV2Library.quote(amountADesired, reserveA, reserveB);
                              if (amountBOptimal <= amountBDesired) {
                                  require(amountBOptimal >= amountBMin, 'UniswapV2Router: INSUFFICIENT_B_AMOUNT');
                                  (amountA, amountB) = (amountADesired, amountBOptimal);
                              } else {
                                  uint amountAOptimal = UniswapV2Library.quote(amountBDesired, reserveB, reserveA);
                                  assert(amountAOptimal <= amountADesired);
                                  require(amountAOptimal >= amountAMin, 'UniswapV2Router: INSUFFICIENT_A_AMOUNT');
                                  (amountA, amountB) = (amountAOptimal, amountBDesired);
                              }
                          }
                      }
                      function addLiquidity(
                          address tokenA,
                          address tokenB,
                          uint amountADesired,
                          uint amountBDesired,
                          uint amountAMin,
                          uint amountBMin,
                          address to,
                          uint deadline
                      ) external virtual override ensure(deadline) returns (uint amountA, uint amountB, uint liquidity) {
                          (amountA, amountB) = _addLiquidity(tokenA, tokenB, amountADesired, amountBDesired, amountAMin, amountBMin);
                          address pair = UniswapV2Library.pairFor(factory, tokenA, tokenB);
                          TransferHelper.safeTransferFrom(tokenA, msg.sender, pair, amountA);
                          TransferHelper.safeTransferFrom(tokenB, msg.sender, pair, amountB);
                          liquidity = IUniswapV2Pair(pair).mint(to);
                      }
                      function addLiquidityETH(
                          address token,
                          uint amountTokenDesired,
                          uint amountTokenMin,
                          uint amountETHMin,
                          address to,
                          uint deadline
                      ) external virtual override payable ensure(deadline) returns (uint amountToken, uint amountETH, uint liquidity) {
                          (amountToken, amountETH) = _addLiquidity(
                              token,
                              WETH,
                              amountTokenDesired,
                              msg.value,
                              amountTokenMin,
                              amountETHMin
                          );
                          address pair = UniswapV2Library.pairFor(factory, token, WETH);
                          TransferHelper.safeTransferFrom(token, msg.sender, pair, amountToken);
                          IWETH(WETH).deposit{value: amountETH}();
                          assert(IWETH(WETH).transfer(pair, amountETH));
                          liquidity = IUniswapV2Pair(pair).mint(to);
                          // refund dust eth, if any
                          if (msg.value > amountETH) TransferHelper.safeTransferETH(msg.sender, msg.value - amountETH);
                      }
                  
                      // **** REMOVE LIQUIDITY ****
                      function removeLiquidity(
                          address tokenA,
                          address tokenB,
                          uint liquidity,
                          uint amountAMin,
                          uint amountBMin,
                          address to,
                          uint deadline
                      ) public virtual override ensure(deadline) returns (uint amountA, uint amountB) {
                          address pair = UniswapV2Library.pairFor(factory, tokenA, tokenB);
                          IUniswapV2Pair(pair).transferFrom(msg.sender, pair, liquidity); // send liquidity to pair
                          (uint amount0, uint amount1) = IUniswapV2Pair(pair).burn(to);
                          (address token0,) = UniswapV2Library.sortTokens(tokenA, tokenB);
                          (amountA, amountB) = tokenA == token0 ? (amount0, amount1) : (amount1, amount0);
                          require(amountA >= amountAMin, 'UniswapV2Router: INSUFFICIENT_A_AMOUNT');
                          require(amountB >= amountBMin, 'UniswapV2Router: INSUFFICIENT_B_AMOUNT');
                      }
                      function removeLiquidityETH(
                          address token,
                          uint liquidity,
                          uint amountTokenMin,
                          uint amountETHMin,
                          address to,
                          uint deadline
                      ) public virtual override ensure(deadline) returns (uint amountToken, uint amountETH) {
                          (amountToken, amountETH) = removeLiquidity(
                              token,
                              WETH,
                              liquidity,
                              amountTokenMin,
                              amountETHMin,
                              address(this),
                              deadline
                          );
                          TransferHelper.safeTransfer(token, to, amountToken);
                          IWETH(WETH).withdraw(amountETH);
                          TransferHelper.safeTransferETH(to, amountETH);
                      }
                      function removeLiquidityWithPermit(
                          address tokenA,
                          address tokenB,
                          uint liquidity,
                          uint amountAMin,
                          uint amountBMin,
                          address to,
                          uint deadline,
                          bool approveMax, uint8 v, bytes32 r, bytes32 s
                      ) external virtual override returns (uint amountA, uint amountB) {
                          address pair = UniswapV2Library.pairFor(factory, tokenA, tokenB);
                          uint value = approveMax ? uint(-1) : liquidity;
                          IUniswapV2Pair(pair).permit(msg.sender, address(this), value, deadline, v, r, s);
                          (amountA, amountB) = removeLiquidity(tokenA, tokenB, liquidity, amountAMin, amountBMin, to, deadline);
                      }
                      function removeLiquidityETHWithPermit(
                          address token,
                          uint liquidity,
                          uint amountTokenMin,
                          uint amountETHMin,
                          address to,
                          uint deadline,
                          bool approveMax, uint8 v, bytes32 r, bytes32 s
                      ) external virtual override returns (uint amountToken, uint amountETH) {
                          address pair = UniswapV2Library.pairFor(factory, token, WETH);
                          uint value = approveMax ? uint(-1) : liquidity;
                          IUniswapV2Pair(pair).permit(msg.sender, address(this), value, deadline, v, r, s);
                          (amountToken, amountETH) = removeLiquidityETH(token, liquidity, amountTokenMin, amountETHMin, to, deadline);
                      }
                  
                      // **** REMOVE LIQUIDITY (supporting fee-on-transfer tokens) ****
                      function removeLiquidityETHSupportingFeeOnTransferTokens(
                          address token,
                          uint liquidity,
                          uint amountTokenMin,
                          uint amountETHMin,
                          address to,
                          uint deadline
                      ) public virtual override ensure(deadline) returns (uint amountETH) {
                          (, amountETH) = removeLiquidity(
                              token,
                              WETH,
                              liquidity,
                              amountTokenMin,
                              amountETHMin,
                              address(this),
                              deadline
                          );
                          TransferHelper.safeTransfer(token, to, IERC20(token).balanceOf(address(this)));
                          IWETH(WETH).withdraw(amountETH);
                          TransferHelper.safeTransferETH(to, amountETH);
                      }
                      function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
                          address token,
                          uint liquidity,
                          uint amountTokenMin,
                          uint amountETHMin,
                          address to,
                          uint deadline,
                          bool approveMax, uint8 v, bytes32 r, bytes32 s
                      ) external virtual override returns (uint amountETH) {
                          address pair = UniswapV2Library.pairFor(factory, token, WETH);
                          uint value = approveMax ? uint(-1) : liquidity;
                          IUniswapV2Pair(pair).permit(msg.sender, address(this), value, deadline, v, r, s);
                          amountETH = removeLiquidityETHSupportingFeeOnTransferTokens(
                              token, liquidity, amountTokenMin, amountETHMin, to, deadline
                          );
                      }
                  
                      // **** SWAP ****
                      // requires the initial amount to have already been sent to the first pair
                      function _swap(uint[] memory amounts, address[] memory path, address _to) internal virtual {
                          for (uint i; i < path.length - 1; i++) {
                              (address input, address output) = (path[i], path[i + 1]);
                              (address token0,) = UniswapV2Library.sortTokens(input, output);
                              uint amountOut = amounts[i + 1];
                              (uint amount0Out, uint amount1Out) = input == token0 ? (uint(0), amountOut) : (amountOut, uint(0));
                              address to = i < path.length - 2 ? UniswapV2Library.pairFor(factory, output, path[i + 2]) : _to;
                              IUniswapV2Pair(UniswapV2Library.pairFor(factory, input, output)).swap(
                                  amount0Out, amount1Out, to, new bytes(0)
                              );
                          }
                      }
                      function swapExactTokensForTokens(
                          uint amountIn,
                          uint amountOutMin,
                          address[] calldata path,
                          address to,
                          uint deadline
                      ) external virtual override ensure(deadline) returns (uint[] memory amounts) {
                          amounts = UniswapV2Library.getAmountsOut(factory, amountIn, path);
                          require(amounts[amounts.length - 1] >= amountOutMin, 'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT');
                          TransferHelper.safeTransferFrom(
                              path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0]
                          );
                          _swap(amounts, path, to);
                      }
                      function swapTokensForExactTokens(
                          uint amountOut,
                          uint amountInMax,
                          address[] calldata path,
                          address to,
                          uint deadline
                      ) external virtual override ensure(deadline) returns (uint[] memory amounts) {
                          amounts = UniswapV2Library.getAmountsIn(factory, amountOut, path);
                          require(amounts[0] <= amountInMax, 'UniswapV2Router: EXCESSIVE_INPUT_AMOUNT');
                          TransferHelper.safeTransferFrom(
                              path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0]
                          );
                          _swap(amounts, path, to);
                      }
                      function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline)
                          external
                          virtual
                          override
                          payable
                          ensure(deadline)
                          returns (uint[] memory amounts)
                      {
                          require(path[0] == WETH, 'UniswapV2Router: INVALID_PATH');
                          amounts = UniswapV2Library.getAmountsOut(factory, msg.value, path);
                          require(amounts[amounts.length - 1] >= amountOutMin, 'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT');
                          IWETH(WETH).deposit{value: amounts[0]}();
                          assert(IWETH(WETH).transfer(UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0]));
                          _swap(amounts, path, to);
                      }
                      function swapTokensForExactETH(uint amountOut, uint amountInMax, address[] calldata path, address to, uint deadline)
                          external
                          virtual
                          override
                          ensure(deadline)
                          returns (uint[] memory amounts)
                      {
                          require(path[path.length - 1] == WETH, 'UniswapV2Router: INVALID_PATH');
                          amounts = UniswapV2Library.getAmountsIn(factory, amountOut, path);
                          require(amounts[0] <= amountInMax, 'UniswapV2Router: EXCESSIVE_INPUT_AMOUNT');
                          TransferHelper.safeTransferFrom(
                              path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0]
                          );
                          _swap(amounts, path, address(this));
                          IWETH(WETH).withdraw(amounts[amounts.length - 1]);
                          TransferHelper.safeTransferETH(to, amounts[amounts.length - 1]);
                      }
                      function swapExactTokensForETH(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline)
                          external
                          virtual
                          override
                          ensure(deadline)
                          returns (uint[] memory amounts)
                      {
                          require(path[path.length - 1] == WETH, 'UniswapV2Router: INVALID_PATH');
                          amounts = UniswapV2Library.getAmountsOut(factory, amountIn, path);
                          require(amounts[amounts.length - 1] >= amountOutMin, 'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT');
                          TransferHelper.safeTransferFrom(
                              path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0]
                          );
                          _swap(amounts, path, address(this));
                          IWETH(WETH).withdraw(amounts[amounts.length - 1]);
                          TransferHelper.safeTransferETH(to, amounts[amounts.length - 1]);
                      }
                      function swapETHForExactTokens(uint amountOut, address[] calldata path, address to, uint deadline)
                          external
                          virtual
                          override
                          payable
                          ensure(deadline)
                          returns (uint[] memory amounts)
                      {
                          require(path[0] == WETH, 'UniswapV2Router: INVALID_PATH');
                          amounts = UniswapV2Library.getAmountsIn(factory, amountOut, path);
                          require(amounts[0] <= msg.value, 'UniswapV2Router: EXCESSIVE_INPUT_AMOUNT');
                          IWETH(WETH).deposit{value: amounts[0]}();
                          assert(IWETH(WETH).transfer(UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0]));
                          _swap(amounts, path, to);
                          // refund dust eth, if any
                          if (msg.value > amounts[0]) TransferHelper.safeTransferETH(msg.sender, msg.value - amounts[0]);
                      }
                  
                      // **** SWAP (supporting fee-on-transfer tokens) ****
                      // requires the initial amount to have already been sent to the first pair
                      function _swapSupportingFeeOnTransferTokens(address[] memory path, address _to) internal virtual {
                          for (uint i; i < path.length - 1; i++) {
                              (address input, address output) = (path[i], path[i + 1]);
                              (address token0,) = UniswapV2Library.sortTokens(input, output);
                              IUniswapV2Pair pair = IUniswapV2Pair(UniswapV2Library.pairFor(factory, input, output));
                              uint amountInput;
                              uint amountOutput;
                              { // scope to avoid stack too deep errors
                              (uint reserve0, uint reserve1,) = pair.getReserves();
                              (uint reserveInput, uint reserveOutput) = input == token0 ? (reserve0, reserve1) : (reserve1, reserve0);
                              amountInput = IERC20(input).balanceOf(address(pair)).sub(reserveInput);
                              amountOutput = UniswapV2Library.getAmountOut(amountInput, reserveInput, reserveOutput);
                              }
                              (uint amount0Out, uint amount1Out) = input == token0 ? (uint(0), amountOutput) : (amountOutput, uint(0));
                              address to = i < path.length - 2 ? UniswapV2Library.pairFor(factory, output, path[i + 2]) : _to;
                              pair.swap(amount0Out, amount1Out, to, new bytes(0));
                          }
                      }
                      function swapExactTokensForTokensSupportingFeeOnTransferTokens(
                          uint amountIn,
                          uint amountOutMin,
                          address[] calldata path,
                          address to,
                          uint deadline
                      ) external virtual override ensure(deadline) {
                          TransferHelper.safeTransferFrom(
                              path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amountIn
                          );
                          uint balanceBefore = IERC20(path[path.length - 1]).balanceOf(to);
                          _swapSupportingFeeOnTransferTokens(path, to);
                          require(
                              IERC20(path[path.length - 1]).balanceOf(to).sub(balanceBefore) >= amountOutMin,
                              'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT'
                          );
                      }
                      function swapExactETHForTokensSupportingFeeOnTransferTokens(
                          uint amountOutMin,
                          address[] calldata path,
                          address to,
                          uint deadline
                      )
                          external
                          virtual
                          override
                          payable
                          ensure(deadline)
                      {
                          require(path[0] == WETH, 'UniswapV2Router: INVALID_PATH');
                          uint amountIn = msg.value;
                          IWETH(WETH).deposit{value: amountIn}();
                          assert(IWETH(WETH).transfer(UniswapV2Library.pairFor(factory, path[0], path[1]), amountIn));
                          uint balanceBefore = IERC20(path[path.length - 1]).balanceOf(to);
                          _swapSupportingFeeOnTransferTokens(path, to);
                          require(
                              IERC20(path[path.length - 1]).balanceOf(to).sub(balanceBefore) >= amountOutMin,
                              'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT'
                          );
                      }
                      function swapExactTokensForETHSupportingFeeOnTransferTokens(
                          uint amountIn,
                          uint amountOutMin,
                          address[] calldata path,
                          address to,
                          uint deadline
                      )
                          external
                          virtual
                          override
                          ensure(deadline)
                      {
                          require(path[path.length - 1] == WETH, 'UniswapV2Router: INVALID_PATH');
                          TransferHelper.safeTransferFrom(
                              path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amountIn
                          );
                          _swapSupportingFeeOnTransferTokens(path, address(this));
                          uint amountOut = IERC20(WETH).balanceOf(address(this));
                          require(amountOut >= amountOutMin, 'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT');
                          IWETH(WETH).withdraw(amountOut);
                          TransferHelper.safeTransferETH(to, amountOut);
                      }
                  
                      // **** LIBRARY FUNCTIONS ****
                      function quote(uint amountA, uint reserveA, uint reserveB) public pure virtual override returns (uint amountB) {
                          return UniswapV2Library.quote(amountA, reserveA, reserveB);
                      }
                  
                      function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut)
                          public
                          pure
                          virtual
                          override
                          returns (uint amountOut)
                      {
                          return UniswapV2Library.getAmountOut(amountIn, reserveIn, reserveOut);
                      }
                  
                      function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut)
                          public
                          pure
                          virtual
                          override
                          returns (uint amountIn)
                      {
                          return UniswapV2Library.getAmountIn(amountOut, reserveIn, reserveOut);
                      }
                  
                      function getAmountsOut(uint amountIn, address[] memory path)
                          public
                          view
                          virtual
                          override
                          returns (uint[] memory amounts)
                      {
                          return UniswapV2Library.getAmountsOut(factory, amountIn, path);
                      }
                  
                      function getAmountsIn(uint amountOut, address[] memory path)
                          public
                          view
                          virtual
                          override
                          returns (uint[] memory amounts)
                      {
                          return UniswapV2Library.getAmountsIn(factory, amountOut, path);
                      }
                  }
                  
                  // a library for performing overflow-safe math, courtesy of DappHub (https://github.com/dapphub/ds-math)
                  
                  library SafeMath {
                      function add(uint x, uint y) internal pure returns (uint z) {
                          require((z = x + y) >= x, 'ds-math-add-overflow');
                      }
                  
                      function sub(uint x, uint y) internal pure returns (uint z) {
                          require((z = x - y) <= x, 'ds-math-sub-underflow');
                      }
                  
                      function mul(uint x, uint y) internal pure returns (uint z) {
                          require(y == 0 || (z = x * y) / y == x, 'ds-math-mul-overflow');
                      }
                  }
                  
                  library UniswapV2Library {
                      using SafeMath for uint;
                  
                      // returns sorted token addresses, used to handle return values from pairs sorted in this order
                      function sortTokens(address tokenA, address tokenB) internal pure returns (address token0, address token1) {
                          require(tokenA != tokenB, 'UniswapV2Library: IDENTICAL_ADDRESSES');
                          (token0, token1) = tokenA < tokenB ? (tokenA, tokenB) : (tokenB, tokenA);
                          require(token0 != address(0), 'UniswapV2Library: ZERO_ADDRESS');
                      }
                  
                      // calculates the CREATE2 address for a pair without making any external calls
                      function pairFor(address factory, address tokenA, address tokenB) internal pure returns (address pair) {
                          (address token0, address token1) = sortTokens(tokenA, tokenB);
                          pair = address(uint(keccak256(abi.encodePacked(
                                  hex'ff',
                                  factory,
                                  keccak256(abi.encodePacked(token0, token1)),
                                  hex'96e8ac4277198ff8b6f785478aa9a39f403cb768dd02cbee326c3e7da348845f' // init code hash
                              ))));
                      }
                  
                      // fetches and sorts the reserves for a pair
                      function getReserves(address factory, address tokenA, address tokenB) internal view returns (uint reserveA, uint reserveB) {
                          (address token0,) = sortTokens(tokenA, tokenB);
                          (uint reserve0, uint reserve1,) = IUniswapV2Pair(pairFor(factory, tokenA, tokenB)).getReserves();
                          (reserveA, reserveB) = tokenA == token0 ? (reserve0, reserve1) : (reserve1, reserve0);
                      }
                  
                      // given some amount of an asset and pair reserves, returns an equivalent amount of the other asset
                      function quote(uint amountA, uint reserveA, uint reserveB) internal pure returns (uint amountB) {
                          require(amountA > 0, 'UniswapV2Library: INSUFFICIENT_AMOUNT');
                          require(reserveA > 0 && reserveB > 0, 'UniswapV2Library: INSUFFICIENT_LIQUIDITY');
                          amountB = amountA.mul(reserveB) / reserveA;
                      }
                  
                      // given an input amount of an asset and pair reserves, returns the maximum output amount of the other asset
                      function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut) internal pure returns (uint amountOut) {
                          require(amountIn > 0, 'UniswapV2Library: INSUFFICIENT_INPUT_AMOUNT');
                          require(reserveIn > 0 && reserveOut > 0, 'UniswapV2Library: INSUFFICIENT_LIQUIDITY');
                          uint amountInWithFee = amountIn.mul(997);
                          uint numerator = amountInWithFee.mul(reserveOut);
                          uint denominator = reserveIn.mul(1000).add(amountInWithFee);
                          amountOut = numerator / denominator;
                      }
                  
                      // given an output amount of an asset and pair reserves, returns a required input amount of the other asset
                      function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut) internal pure returns (uint amountIn) {
                          require(amountOut > 0, 'UniswapV2Library: INSUFFICIENT_OUTPUT_AMOUNT');
                          require(reserveIn > 0 && reserveOut > 0, 'UniswapV2Library: INSUFFICIENT_LIQUIDITY');
                          uint numerator = reserveIn.mul(amountOut).mul(1000);
                          uint denominator = reserveOut.sub(amountOut).mul(997);
                          amountIn = (numerator / denominator).add(1);
                      }
                  
                      // performs chained getAmountOut calculations on any number of pairs
                      function getAmountsOut(address factory, uint amountIn, address[] memory path) internal view returns (uint[] memory amounts) {
                          require(path.length >= 2, 'UniswapV2Library: INVALID_PATH');
                          amounts = new uint[](path.length);
                          amounts[0] = amountIn;
                          for (uint i; i < path.length - 1; i++) {
                              (uint reserveIn, uint reserveOut) = getReserves(factory, path[i], path[i + 1]);
                              amounts[i + 1] = getAmountOut(amounts[i], reserveIn, reserveOut);
                          }
                      }
                  
                      // performs chained getAmountIn calculations on any number of pairs
                      function getAmountsIn(address factory, uint amountOut, address[] memory path) internal view returns (uint[] memory amounts) {
                          require(path.length >= 2, 'UniswapV2Library: INVALID_PATH');
                          amounts = new uint[](path.length);
                          amounts[amounts.length - 1] = amountOut;
                          for (uint i = path.length - 1; i > 0; i--) {
                              (uint reserveIn, uint reserveOut) = getReserves(factory, path[i - 1], path[i]);
                              amounts[i - 1] = getAmountIn(amounts[i], reserveIn, reserveOut);
                          }
                      }
                  }
                  
                  // helper methods for interacting with ERC20 tokens and sending ETH that do not consistently return true/false
                  library TransferHelper {
                      function safeApprove(address token, address to, uint value) internal {
                          // bytes4(keccak256(bytes('approve(address,uint256)')));
                          (bool success, bytes memory data) = token.call(abi.encodeWithSelector(0x095ea7b3, to, value));
                          require(success && (data.length == 0 || abi.decode(data, (bool))), 'TransferHelper: APPROVE_FAILED');
                      }
                  
                      function safeTransfer(address token, address to, uint value) internal {
                          // bytes4(keccak256(bytes('transfer(address,uint256)')));
                          (bool success, bytes memory data) = token.call(abi.encodeWithSelector(0xa9059cbb, to, value));
                          require(success && (data.length == 0 || abi.decode(data, (bool))), 'TransferHelper: TRANSFER_FAILED');
                      }
                  
                      function safeTransferFrom(address token, address from, address to, uint value) internal {
                          // bytes4(keccak256(bytes('transferFrom(address,address,uint256)')));
                          (bool success, bytes memory data) = token.call(abi.encodeWithSelector(0x23b872dd, from, to, value));
                          require(success && (data.length == 0 || abi.decode(data, (bool))), 'TransferHelper: TRANSFER_FROM_FAILED');
                      }
                  
                      function safeTransferETH(address to, uint value) internal {
                          (bool success,) = to.call{value:value}(new bytes(0));
                          require(success, 'TransferHelper: ETH_TRANSFER_FAILED');
                      }
                  }

                  File 6 of 7: EACAggregatorProxy
                  pragma solidity 0.6.6;
                  
                  
                  /**
                   * @title The Owned contract
                   * @notice A contract with helpers for basic contract ownership.
                   */
                  contract Owned {
                  
                    address payable public owner;
                    address private pendingOwner;
                  
                    event OwnershipTransferRequested(
                      address indexed from,
                      address indexed to
                    );
                    event OwnershipTransferred(
                      address indexed from,
                      address indexed to
                    );
                  
                    constructor() public {
                      owner = msg.sender;
                    }
                  
                    /**
                     * @dev Allows an owner to begin transferring ownership to a new address,
                     * pending.
                     */
                    function transferOwnership(address _to)
                      external
                      onlyOwner()
                    {
                      pendingOwner = _to;
                  
                      emit OwnershipTransferRequested(owner, _to);
                    }
                  
                    /**
                     * @dev Allows an ownership transfer to be completed by the recipient.
                     */
                    function acceptOwnership()
                      external
                    {
                      require(msg.sender == pendingOwner, "Must be proposed owner");
                  
                      address oldOwner = owner;
                      owner = msg.sender;
                      pendingOwner = address(0);
                  
                      emit OwnershipTransferred(oldOwner, msg.sender);
                    }
                  
                    /**
                     * @dev Reverts if called by anyone other than the contract owner.
                     */
                    modifier onlyOwner() {
                      require(msg.sender == owner, "Only callable by owner");
                      _;
                    }
                  
                  }
                  
                  interface AggregatorInterface {
                    function latestAnswer() external view returns (int256);
                    function latestTimestamp() external view returns (uint256);
                    function latestRound() external view returns (uint256);
                    function getAnswer(uint256 roundId) external view returns (int256);
                    function getTimestamp(uint256 roundId) external view returns (uint256);
                  
                    event AnswerUpdated(int256 indexed current, uint256 indexed roundId, uint256 updatedAt);
                    event NewRound(uint256 indexed roundId, address indexed startedBy, uint256 startedAt);
                  }
                  
                  interface AggregatorV3Interface {
                  
                    function decimals() external view returns (uint8);
                    function description() external view returns (string memory);
                    function version() external view returns (uint256);
                  
                    // getRoundData and latestRoundData should both raise "No data present"
                    // if they do not have data to report, instead of returning unset values
                    // which could be misinterpreted as actual reported values.
                    function getRoundData(uint80 _roundId)
                      external
                      view
                      returns (
                        uint80 roundId,
                        int256 answer,
                        uint256 startedAt,
                        uint256 updatedAt,
                        uint80 answeredInRound
                      );
                    function latestRoundData()
                      external
                      view
                      returns (
                        uint80 roundId,
                        int256 answer,
                        uint256 startedAt,
                        uint256 updatedAt,
                        uint80 answeredInRound
                      );
                  
                  }
                  
                  interface AggregatorV2V3Interface is AggregatorInterface, AggregatorV3Interface
                  {
                  }
                  
                  /**
                   * @title A trusted proxy for updating where current answers are read from
                   * @notice This contract provides a consistent address for the
                   * CurrentAnwerInterface but delegates where it reads from to the owner, who is
                   * trusted to update it.
                   */
                  contract AggregatorProxy is AggregatorV2V3Interface, Owned {
                  
                    struct Phase {
                      uint16 id;
                      AggregatorV2V3Interface aggregator;
                    }
                    Phase private currentPhase;
                    AggregatorV2V3Interface public proposedAggregator;
                    mapping(uint16 => AggregatorV2V3Interface) public phaseAggregators;
                  
                    uint256 constant private PHASE_OFFSET = 64;
                    uint256 constant private PHASE_SIZE = 16;
                    uint256 constant private MAX_ID = 2**(PHASE_OFFSET+PHASE_SIZE) - 1;
                  
                    constructor(address _aggregator) public Owned() {
                      setAggregator(_aggregator);
                    }
                  
                    /**
                     * @notice Reads the current answer from aggregator delegated to.
                     *
                     * @dev #[deprecated] Use latestRoundData instead. This does not error if no
                     * answer has been reached, it will simply return 0. Either wait to point to
                     * an already answered Aggregator or use the recommended latestRoundData
                     * instead which includes better verification information.
                     */
                    function latestAnswer()
                      public
                      view
                      virtual
                      override
                      returns (int256 answer)
                    {
                      return currentPhase.aggregator.latestAnswer();
                    }
                  
                    /**
                     * @notice Reads the last updated height from aggregator delegated to.
                     *
                     * @dev #[deprecated] Use latestRoundData instead. This does not error if no
                     * answer has been reached, it will simply return 0. Either wait to point to
                     * an already answered Aggregator or use the recommended latestRoundData
                     * instead which includes better verification information.
                     */
                    function latestTimestamp()
                      public
                      view
                      virtual
                      override
                      returns (uint256 updatedAt)
                    {
                      return currentPhase.aggregator.latestTimestamp();
                    }
                  
                    /**
                     * @notice get past rounds answers
                     * @param _roundId the answer number to retrieve the answer for
                     *
                     * @dev #[deprecated] Use getRoundData instead. This does not error if no
                     * answer has been reached, it will simply return 0. Either wait to point to
                     * an already answered Aggregator or use the recommended getRoundData
                     * instead which includes better verification information.
                     */
                    function getAnswer(uint256 _roundId)
                      public
                      view
                      virtual
                      override
                      returns (int256 answer)
                    {
                      if (_roundId > MAX_ID) return 0;
                  
                      (uint16 phaseId, uint64 aggregatorRoundId) = parseIds(_roundId);
                      AggregatorV2V3Interface aggregator = phaseAggregators[phaseId];
                      if (address(aggregator) == address(0)) return 0;
                  
                      return aggregator.getAnswer(aggregatorRoundId);
                    }
                  
                    /**
                     * @notice get block timestamp when an answer was last updated
                     * @param _roundId the answer number to retrieve the updated timestamp for
                     *
                     * @dev #[deprecated] Use getRoundData instead. This does not error if no
                     * answer has been reached, it will simply return 0. Either wait to point to
                     * an already answered Aggregator or use the recommended getRoundData
                     * instead which includes better verification information.
                     */
                    function getTimestamp(uint256 _roundId)
                      public
                      view
                      virtual
                      override
                      returns (uint256 updatedAt)
                    {
                      if (_roundId > MAX_ID) return 0;
                  
                      (uint16 phaseId, uint64 aggregatorRoundId) = parseIds(_roundId);
                      AggregatorV2V3Interface aggregator = phaseAggregators[phaseId];
                      if (address(aggregator) == address(0)) return 0;
                  
                      return aggregator.getTimestamp(aggregatorRoundId);
                    }
                  
                    /**
                     * @notice get the latest completed round where the answer was updated. This
                     * ID includes the proxy's phase, to make sure round IDs increase even when
                     * switching to a newly deployed aggregator.
                     *
                     * @dev #[deprecated] Use latestRoundData instead. This does not error if no
                     * answer has been reached, it will simply return 0. Either wait to point to
                     * an already answered Aggregator or use the recommended latestRoundData
                     * instead which includes better verification information.
                     */
                    function latestRound()
                      public
                      view
                      virtual
                      override
                      returns (uint256 roundId)
                    {
                      Phase memory phase = currentPhase; // cache storage reads
                      return addPhase(phase.id, uint64(phase.aggregator.latestRound()));
                    }
                  
                    /**
                     * @notice get data about a round. Consumers are encouraged to check
                     * that they're receiving fresh data by inspecting the updatedAt and
                     * answeredInRound return values.
                     * Note that different underlying implementations of AggregatorV3Interface
                     * have slightly different semantics for some of the return values. Consumers
                     * should determine what implementations they expect to receive
                     * data from and validate that they can properly handle return data from all
                     * of them.
                     * @param _roundId the requested round ID as presented through the proxy, this
                     * is made up of the aggregator's round ID with the phase ID encoded in the
                     * two highest order bytes
                     * @return roundId is the round ID from the aggregator for which the data was
                     * retrieved combined with an phase to ensure that round IDs get larger as
                     * time moves forward.
                     * @return answer is the answer for the given round
                     * @return startedAt is the timestamp when the round was started.
                     * (Only some AggregatorV3Interface implementations return meaningful values)
                     * @return updatedAt is the timestamp when the round last was updated (i.e.
                     * answer was last computed)
                     * @return answeredInRound is the round ID of the round in which the answer
                     * was computed.
                     * (Only some AggregatorV3Interface implementations return meaningful values)
                     * @dev Note that answer and updatedAt may change between queries.
                     */
                    function getRoundData(uint80 _roundId)
                      public
                      view
                      virtual
                      override
                      returns (
                        uint80 roundId,
                        int256 answer,
                        uint256 startedAt,
                        uint256 updatedAt,
                        uint80 answeredInRound
                      )
                    {
                      (uint16 phaseId, uint64 aggregatorRoundId) = parseIds(_roundId);
                  
                      (
                        uint80 roundId,
                        int256 answer,
                        uint256 startedAt,
                        uint256 updatedAt,
                        uint80 ansIn
                      ) = phaseAggregators[phaseId].getRoundData(aggregatorRoundId);
                  
                      return addPhaseIds(roundId, answer, startedAt, updatedAt, ansIn, phaseId);
                    }
                  
                    /**
                     * @notice get data about the latest round. Consumers are encouraged to check
                     * that they're receiving fresh data by inspecting the updatedAt and
                     * answeredInRound return values.
                     * Note that different underlying implementations of AggregatorV3Interface
                     * have slightly different semantics for some of the return values. Consumers
                     * should determine what implementations they expect to receive
                     * data from and validate that they can properly handle return data from all
                     * of them.
                     * @return roundId is the round ID from the aggregator for which the data was
                     * retrieved combined with an phase to ensure that round IDs get larger as
                     * time moves forward.
                     * @return answer is the answer for the given round
                     * @return startedAt is the timestamp when the round was started.
                     * (Only some AggregatorV3Interface implementations return meaningful values)
                     * @return updatedAt is the timestamp when the round last was updated (i.e.
                     * answer was last computed)
                     * @return answeredInRound is the round ID of the round in which the answer
                     * was computed.
                     * (Only some AggregatorV3Interface implementations return meaningful values)
                     * @dev Note that answer and updatedAt may change between queries.
                     */
                    function latestRoundData()
                      public
                      view
                      virtual
                      override
                      returns (
                        uint80 roundId,
                        int256 answer,
                        uint256 startedAt,
                        uint256 updatedAt,
                        uint80 answeredInRound
                      )
                    {
                      Phase memory current = currentPhase; // cache storage reads
                  
                      (
                        uint80 roundId,
                        int256 answer,
                        uint256 startedAt,
                        uint256 updatedAt,
                        uint80 ansIn
                      ) = current.aggregator.latestRoundData();
                  
                      return addPhaseIds(roundId, answer, startedAt, updatedAt, ansIn, current.id);
                    }
                  
                    /**
                     * @notice Used if an aggregator contract has been proposed.
                     * @param _roundId the round ID to retrieve the round data for
                     * @return roundId is the round ID for which data was retrieved
                     * @return answer is the answer for the given round
                     * @return startedAt is the timestamp when the round was started.
                     * (Only some AggregatorV3Interface implementations return meaningful values)
                     * @return updatedAt is the timestamp when the round last was updated (i.e.
                     * answer was last computed)
                     * @return answeredInRound is the round ID of the round in which the answer
                     * was computed.
                    */
                    function proposedGetRoundData(uint80 _roundId)
                      public
                      view
                      virtual
                      hasProposal()
                      returns (
                        uint80 roundId,
                        int256 answer,
                        uint256 startedAt,
                        uint256 updatedAt,
                        uint80 answeredInRound
                      )
                    {
                      return proposedAggregator.getRoundData(_roundId);
                    }
                  
                    /**
                     * @notice Used if an aggregator contract has been proposed.
                     * @return roundId is the round ID for which data was retrieved
                     * @return answer is the answer for the given round
                     * @return startedAt is the timestamp when the round was started.
                     * (Only some AggregatorV3Interface implementations return meaningful values)
                     * @return updatedAt is the timestamp when the round last was updated (i.e.
                     * answer was last computed)
                     * @return answeredInRound is the round ID of the round in which the answer
                     * was computed.
                    */
                    function proposedLatestRoundData()
                      public
                      view
                      virtual
                      hasProposal()
                      returns (
                        uint80 roundId,
                        int256 answer,
                        uint256 startedAt,
                        uint256 updatedAt,
                        uint80 answeredInRound
                      )
                    {
                      return proposedAggregator.latestRoundData();
                    }
                  
                    /**
                     * @notice returns the current phase's aggregator address.
                     */
                    function aggregator()
                      external
                      view
                      returns (address)
                    {
                      return address(currentPhase.aggregator);
                    }
                  
                    /**
                     * @notice returns the current phase's ID.
                     */
                    function phaseId()
                      external
                      view
                      returns (uint16)
                    {
                      return currentPhase.id;
                    }
                  
                    /**
                     * @notice represents the number of decimals the aggregator responses represent.
                     */
                    function decimals()
                      external
                      view
                      override
                      returns (uint8)
                    {
                      return currentPhase.aggregator.decimals();
                    }
                  
                    /**
                     * @notice the version number representing the type of aggregator the proxy
                     * points to.
                     */
                    function version()
                      external
                      view
                      override
                      returns (uint256)
                    {
                      return currentPhase.aggregator.version();
                    }
                  
                    /**
                     * @notice returns the description of the aggregator the proxy points to.
                     */
                    function description()
                      external
                      view
                      override
                      returns (string memory)
                    {
                      return currentPhase.aggregator.description();
                    }
                  
                    /**
                     * @notice Allows the owner to propose a new address for the aggregator
                     * @param _aggregator The new address for the aggregator contract
                     */
                    function proposeAggregator(address _aggregator)
                      external
                      onlyOwner()
                    {
                      proposedAggregator = AggregatorV2V3Interface(_aggregator);
                    }
                  
                    /**
                     * @notice Allows the owner to confirm and change the address
                     * to the proposed aggregator
                     * @dev Reverts if the given address doesn't match what was previously
                     * proposed
                     * @param _aggregator The new address for the aggregator contract
                     */
                    function confirmAggregator(address _aggregator)
                      external
                      onlyOwner()
                    {
                      require(_aggregator == address(proposedAggregator), "Invalid proposed aggregator");
                      delete proposedAggregator;
                      setAggregator(_aggregator);
                    }
                  
                  
                    /*
                     * Internal
                     */
                  
                    function setAggregator(address _aggregator)
                      internal
                    {
                      uint16 id = currentPhase.id + 1;
                      currentPhase = Phase(id, AggregatorV2V3Interface(_aggregator));
                      phaseAggregators[id] = AggregatorV2V3Interface(_aggregator);
                    }
                  
                    function addPhase(
                      uint16 _phase,
                      uint64 _originalId
                    )
                      internal
                      view
                      returns (uint80)
                    {
                      return uint80(uint256(_phase) << PHASE_OFFSET | _originalId);
                    }
                  
                    function parseIds(
                      uint256 _roundId
                    )
                      internal
                      view
                      returns (uint16, uint64)
                    {
                      uint16 phaseId = uint16(_roundId >> PHASE_OFFSET);
                      uint64 aggregatorRoundId = uint64(_roundId);
                  
                      return (phaseId, aggregatorRoundId);
                    }
                  
                    function addPhaseIds(
                        uint80 roundId,
                        int256 answer,
                        uint256 startedAt,
                        uint256 updatedAt,
                        uint80 answeredInRound,
                        uint16 phaseId
                    )
                      internal
                      view
                      returns (uint80, int256, uint256, uint256, uint80)
                    {
                      return (
                        addPhase(phaseId, uint64(roundId)),
                        answer,
                        startedAt,
                        updatedAt,
                        addPhase(phaseId, uint64(answeredInRound))
                      );
                    }
                  
                    /*
                     * Modifiers
                     */
                  
                    modifier hasProposal() {
                      require(address(proposedAggregator) != address(0), "No proposed aggregator present");
                      _;
                    }
                  
                  }
                  
                  interface AccessControllerInterface {
                    function hasAccess(address user, bytes calldata data) external view returns (bool);
                  }
                  
                  /**
                   * @title External Access Controlled Aggregator Proxy
                   * @notice A trusted proxy for updating where current answers are read from
                   * @notice This contract provides a consistent address for the
                   * Aggregator and AggregatorV3Interface but delegates where it reads from to the owner, who is
                   * trusted to update it.
                   * @notice Only access enabled addresses are allowed to access getters for
                   * aggregated answers and round information.
                   */
                  contract EACAggregatorProxy is AggregatorProxy {
                  
                    AccessControllerInterface public accessController;
                  
                    constructor(
                      address _aggregator,
                      address _accessController
                    )
                      public
                      AggregatorProxy(_aggregator)
                    {
                      setController(_accessController);
                    }
                  
                    /**
                     * @notice Allows the owner to update the accessController contract address.
                     * @param _accessController The new address for the accessController contract
                     */
                    function setController(address _accessController)
                      public
                      onlyOwner()
                    {
                      accessController = AccessControllerInterface(_accessController);
                    }
                  
                    /**
                     * @notice Reads the current answer from aggregator delegated to.
                     * @dev overridden function to add the checkAccess() modifier
                     *
                     * @dev #[deprecated] Use latestRoundData instead. This does not error if no
                     * answer has been reached, it will simply return 0. Either wait to point to
                     * an already answered Aggregator or use the recommended latestRoundData
                     * instead which includes better verification information.
                     */
                    function latestAnswer()
                      public
                      view
                      override
                      checkAccess()
                      returns (int256)
                    {
                      return super.latestAnswer();
                    }
                  
                    /**
                     * @notice get the latest completed round where the answer was updated. This
                     * ID includes the proxy's phase, to make sure round IDs increase even when
                     * switching to a newly deployed aggregator.
                     *
                     * @dev #[deprecated] Use latestRoundData instead. This does not error if no
                     * answer has been reached, it will simply return 0. Either wait to point to
                     * an already answered Aggregator or use the recommended latestRoundData
                     * instead which includes better verification information.
                     */
                    function latestTimestamp()
                      public
                      view
                      override
                      checkAccess()
                      returns (uint256)
                    {
                      return super.latestTimestamp();
                    }
                  
                    /**
                     * @notice get past rounds answers
                     * @param _roundId the answer number to retrieve the answer for
                     * @dev overridden function to add the checkAccess() modifier
                     *
                     * @dev #[deprecated] Use getRoundData instead. This does not error if no
                     * answer has been reached, it will simply return 0. Either wait to point to
                     * an already answered Aggregator or use the recommended getRoundData
                     * instead which includes better verification information.
                     */
                    function getAnswer(uint256 _roundId)
                      public
                      view
                      override
                      checkAccess()
                      returns (int256)
                    {
                      return super.getAnswer(_roundId);
                    }
                  
                    /**
                     * @notice get block timestamp when an answer was last updated
                     * @param _roundId the answer number to retrieve the updated timestamp for
                     * @dev overridden function to add the checkAccess() modifier
                     *
                     * @dev #[deprecated] Use getRoundData instead. This does not error if no
                     * answer has been reached, it will simply return 0. Either wait to point to
                     * an already answered Aggregator or use the recommended getRoundData
                     * instead which includes better verification information.
                     */
                    function getTimestamp(uint256 _roundId)
                      public
                      view
                      override
                      checkAccess()
                      returns (uint256)
                    {
                      return super.getTimestamp(_roundId);
                    }
                  
                    /**
                     * @notice get the latest completed round where the answer was updated
                     * @dev overridden function to add the checkAccess() modifier
                     *
                     * @dev #[deprecated] Use latestRoundData instead. This does not error if no
                     * answer has been reached, it will simply return 0. Either wait to point to
                     * an already answered Aggregator or use the recommended latestRoundData
                     * instead which includes better verification information.
                     */
                    function latestRound()
                      public
                      view
                      override
                      checkAccess()
                      returns (uint256)
                    {
                      return super.latestRound();
                    }
                  
                    /**
                     * @notice get data about a round. Consumers are encouraged to check
                     * that they're receiving fresh data by inspecting the updatedAt and
                     * answeredInRound return values.
                     * Note that different underlying implementations of AggregatorV3Interface
                     * have slightly different semantics for some of the return values. Consumers
                     * should determine what implementations they expect to receive
                     * data from and validate that they can properly handle return data from all
                     * of them.
                     * @param _roundId the round ID to retrieve the round data for
                     * @return roundId is the round ID from the aggregator for which the data was
                     * retrieved combined with a phase to ensure that round IDs get larger as
                     * time moves forward.
                     * @return answer is the answer for the given round
                     * @return startedAt is the timestamp when the round was started.
                     * (Only some AggregatorV3Interface implementations return meaningful values)
                     * @return updatedAt is the timestamp when the round last was updated (i.e.
                     * answer was last computed)
                     * @return answeredInRound is the round ID of the round in which the answer
                     * was computed.
                     * (Only some AggregatorV3Interface implementations return meaningful values)
                     * @dev Note that answer and updatedAt may change between queries.
                     */
                    function getRoundData(uint80 _roundId)
                      public
                      view
                      checkAccess()
                      override
                      returns (
                        uint80 roundId,
                        int256 answer,
                        uint256 startedAt,
                        uint256 updatedAt,
                        uint80 answeredInRound
                      )
                    {
                      return super.getRoundData(_roundId);
                    }
                  
                    /**
                     * @notice get data about the latest round. Consumers are encouraged to check
                     * that they're receiving fresh data by inspecting the updatedAt and
                     * answeredInRound return values.
                     * Note that different underlying implementations of AggregatorV3Interface
                     * have slightly different semantics for some of the return values. Consumers
                     * should determine what implementations they expect to receive
                     * data from and validate that they can properly handle return data from all
                     * of them.
                     * @return roundId is the round ID from the aggregator for which the data was
                     * retrieved combined with a phase to ensure that round IDs get larger as
                     * time moves forward.
                     * @return answer is the answer for the given round
                     * @return startedAt is the timestamp when the round was started.
                     * (Only some AggregatorV3Interface implementations return meaningful values)
                     * @return updatedAt is the timestamp when the round last was updated (i.e.
                     * answer was last computed)
                     * @return answeredInRound is the round ID of the round in which the answer
                     * was computed.
                     * (Only some AggregatorV3Interface implementations return meaningful values)
                     * @dev Note that answer and updatedAt may change between queries.
                     */
                    function latestRoundData()
                      public
                      view
                      checkAccess()
                      override
                      returns (
                        uint80 roundId,
                        int256 answer,
                        uint256 startedAt,
                        uint256 updatedAt,
                        uint80 answeredInRound
                      )
                    {
                      return super.latestRoundData();
                    }
                  
                    /**
                     * @notice Used if an aggregator contract has been proposed.
                     * @param _roundId the round ID to retrieve the round data for
                     * @return roundId is the round ID for which data was retrieved
                     * @return answer is the answer for the given round
                     * @return startedAt is the timestamp when the round was started.
                     * (Only some AggregatorV3Interface implementations return meaningful values)
                     * @return updatedAt is the timestamp when the round last was updated (i.e.
                     * answer was last computed)
                     * @return answeredInRound is the round ID of the round in which the answer
                     * was computed.
                    */
                    function proposedGetRoundData(uint80 _roundId)
                      public
                      view
                      checkAccess()
                      hasProposal()
                      override
                      returns (
                        uint80 roundId,
                        int256 answer,
                        uint256 startedAt,
                        uint256 updatedAt,
                        uint80 answeredInRound
                      )
                    {
                      return super.proposedGetRoundData(_roundId);
                    }
                  
                    /**
                     * @notice Used if an aggregator contract has been proposed.
                     * @return roundId is the round ID for which data was retrieved
                     * @return answer is the answer for the given round
                     * @return startedAt is the timestamp when the round was started.
                     * (Only some AggregatorV3Interface implementations return meaningful values)
                     * @return updatedAt is the timestamp when the round last was updated (i.e.
                     * answer was last computed)
                     * @return answeredInRound is the round ID of the round in which the answer
                     * was computed.
                    */
                    function proposedLatestRoundData()
                      public
                      view
                      checkAccess()
                      hasProposal()
                      override
                      returns (
                        uint80 roundId,
                        int256 answer,
                        uint256 startedAt,
                        uint256 updatedAt,
                        uint80 answeredInRound
                      )
                    {
                      return super.proposedLatestRoundData();
                    }
                  
                    /**
                     * @dev reverts if the caller does not have access by the accessController
                     * contract or is the contract itself.
                     */
                    modifier checkAccess() {
                      AccessControllerInterface ac = accessController;
                      require(address(ac) == address(0) || ac.hasAccess(msg.sender, msg.data), "No access");
                      _;
                    }
                  }

                  File 7 of 7: AccessControlledOffchainAggregator
                  // SPDX-License-Identifier: MIT
                  pragma solidity ^0.7.1;
                  import "./OffchainAggregator.sol";
                  import "./SimpleReadAccessController.sol";
                  /**
                   * @notice Wrapper of OffchainAggregator which checks read access on Aggregator-interface methods
                   */
                  contract AccessControlledOffchainAggregator is OffchainAggregator, SimpleReadAccessController {
                    constructor(
                      uint32 _maximumGasPrice,
                      uint32 _reasonableGasPrice,
                      uint32 _microLinkPerEth,
                      uint32 _linkGweiPerObservation,
                      uint32 _linkGweiPerTransmission,
                      address _link,
                      int192 _minAnswer,
                      int192 _maxAnswer,
                      AccessControllerInterface _billingAccessController,
                      AccessControllerInterface _requesterAccessController,
                      uint8 _decimals,
                      string memory description
                    )
                      OffchainAggregator(
                        _maximumGasPrice,
                        _reasonableGasPrice,
                        _microLinkPerEth,
                        _linkGweiPerObservation,
                        _linkGweiPerTransmission,
                        _link,
                        _minAnswer,
                        _maxAnswer,
                        _billingAccessController,
                        _requesterAccessController,
                        _decimals,
                        description
                      ) {
                      }
                    /*
                     * Versioning
                     */
                    function typeAndVersion()
                      external
                      override
                      pure
                      virtual
                      returns (string memory)
                    {
                      return "AccessControlledOffchainAggregator 2.0.0";
                    }
                    /*
                     * v2 Aggregator interface
                     */
                    /// @inheritdoc OffchainAggregator
                    function latestAnswer()
                      public
                      override
                      view
                      checkAccess()
                      returns (int256)
                    {
                      return super.latestAnswer();
                    }
                    /// @inheritdoc OffchainAggregator
                    function latestTimestamp()
                      public
                      override
                      view
                      checkAccess()
                      returns (uint256)
                    {
                      return super.latestTimestamp();
                    }
                    /// @inheritdoc OffchainAggregator
                    function latestRound()
                      public
                      override
                      view
                      checkAccess()
                      returns (uint256)
                    {
                      return super.latestRound();
                    }
                    /// @inheritdoc OffchainAggregator
                    function getAnswer(uint256 _roundId)
                      public
                      override
                      view
                      checkAccess()
                      returns (int256)
                    {
                      return super.getAnswer(_roundId);
                    }
                    /// @inheritdoc OffchainAggregator
                    function getTimestamp(uint256 _roundId)
                      public
                      override
                      view
                      checkAccess()
                      returns (uint256)
                    {
                      return super.getTimestamp(_roundId);
                    }
                    /*
                     * v3 Aggregator interface
                     */
                    /// @inheritdoc OffchainAggregator
                    function description()
                      public
                      override
                      view
                      checkAccess()
                      returns (string memory)
                    {
                      return super.description();
                    }
                    /// @inheritdoc OffchainAggregator
                    function getRoundData(uint80 _roundId)
                      public
                      override
                      view
                      checkAccess()
                      returns (
                        uint80 roundId,
                        int256 answer,
                        uint256 startedAt,
                        uint256 updatedAt,
                        uint80 answeredInRound
                      )
                    {
                      return super.getRoundData(_roundId);
                    }
                    /// @inheritdoc OffchainAggregator
                    function latestRoundData()
                      public
                      override
                      view
                      checkAccess()
                      returns (
                        uint80 roundId,
                        int256 answer,
                        uint256 startedAt,
                        uint256 updatedAt,
                        uint80 answeredInRound
                      )
                    {
                      return super.latestRoundData();
                    }
                  }
                  // SPDX-License-Identifier: MIT
                  pragma solidity ^0.7.0;
                  import "./AccessControllerInterface.sol";
                  import "./AggregatorV2V3Interface.sol";
                  import "./AggregatorValidatorInterface.sol";
                  import "./LinkTokenInterface.sol";
                  import "./Owned.sol";
                  import "./OffchainAggregatorBilling.sol";
                  import "./TypeAndVersionInterface.sol";
                  /**
                    * @notice Onchain verification of reports from the offchain reporting protocol
                    * @dev For details on its operation, see the offchain reporting protocol design
                    * @dev doc, which refers to this contract as simply the "contract".
                  */
                  contract OffchainAggregator is Owned, OffchainAggregatorBilling, AggregatorV2V3Interface, TypeAndVersionInterface {
                    uint256 constant private maxUint32 = (1 << 32) - 1;
                    // Storing these fields used on the hot path in a HotVars variable reduces the
                    // retrieval of all of them to a single SLOAD. If any further fields are
                    // added, make sure that storage of the struct still takes at most 32 bytes.
                    struct HotVars {
                      // Provides 128 bits of security against 2nd pre-image attacks, but only
                      // 64 bits against collisions. This is acceptable, since a malicious owner has
                      // easier way of messing up the protocol than to find hash collisions.
                      bytes16 latestConfigDigest;
                      uint40 latestEpochAndRound; // 32 most sig bits for epoch, 8 least sig bits for round
                      // Current bound assumed on number of faulty/dishonest oracles participating
                      // in the protocol, this value is referred to as f in the design
                      uint8 threshold;
                      // Chainlink Aggregators expose a roundId to consumers. The offchain reporting
                      // protocol does not use this id anywhere. We increment it whenever a new
                      // transmission is made to provide callers with contiguous ids for successive
                      // reports.
                      uint32 latestAggregatorRoundId;
                    }
                    HotVars internal s_hotVars;
                    // Transmission records the median answer from the transmit transaction at
                    // time timestamp
                    struct Transmission {
                      int192 answer; // 192 bits ought to be enough for anyone
                      uint64 timestamp;
                    }
                    mapping(uint32 /* aggregator round ID */ => Transmission) internal s_transmissions;
                    // incremented each time a new config is posted. This count is incorporated
                    // into the config digest, to prevent replay attacks.
                    uint32 internal s_configCount;
                    uint32 internal s_latestConfigBlockNumber; // makes it easier for offchain systems
                                                               // to extract config from logs.
                    // Lowest answer the system is allowed to report in response to transmissions
                    int192 immutable public minAnswer;
                    // Highest answer the system is allowed to report in response to transmissions
                    int192 immutable public maxAnswer;
                    /*
                     * @param _maximumGasPrice highest gas price for which transmitter will be compensated
                     * @param _reasonableGasPrice transmitter will receive reward for gas prices under this value
                     * @param _microLinkPerEth reimbursement per ETH of gas cost, in 1e-6LINK units
                     * @param _linkGweiPerObservation reward to oracle for contributing an observation to a successfully transmitted report, in 1e-9LINK units
                     * @param _linkGweiPerTransmission reward to transmitter of a successful report, in 1e-9LINK units
                     * @param _link address of the LINK contract
                     * @param _minAnswer lowest answer the median of a report is allowed to be
                     * @param _maxAnswer highest answer the median of a report is allowed to be
                     * @param _billingAccessController access controller for billing admin functions
                     * @param _requesterAccessController access controller for requesting new rounds
                     * @param _decimals answers are stored in fixed-point format, with this many digits of precision
                     * @param _description short human-readable description of observable this contract's answers pertain to
                     */
                    constructor(
                      uint32 _maximumGasPrice,
                      uint32 _reasonableGasPrice,
                      uint32 _microLinkPerEth,
                      uint32 _linkGweiPerObservation,
                      uint32 _linkGweiPerTransmission,
                      address _link,
                      int192 _minAnswer,
                      int192 _maxAnswer,
                      AccessControllerInterface _billingAccessController,
                      AccessControllerInterface _requesterAccessController,
                      uint8 _decimals,
                      string memory _description
                    )
                      OffchainAggregatorBilling(_maximumGasPrice, _reasonableGasPrice, _microLinkPerEth,
                        _linkGweiPerObservation, _linkGweiPerTransmission, _link,
                        _billingAccessController
                      )
                    {
                      decimals = _decimals;
                      s_description = _description;
                      setRequesterAccessController(_requesterAccessController);
                      setValidatorConfig(AggregatorValidatorInterface(0x0), 0);
                      minAnswer = _minAnswer;
                      maxAnswer = _maxAnswer;
                    }
                    /*
                     * Versioning
                     */
                    function typeAndVersion()
                      external
                      override
                      pure
                      virtual
                      returns (string memory)
                    {
                      return "OffchainAggregator 2.0.0";
                    }
                    /*
                     * Config logic
                     */
                    /**
                     * @notice triggers a new run of the offchain reporting protocol
                     * @param previousConfigBlockNumber block in which the previous config was set, to simplify historic analysis
                     * @param configCount ordinal number of this config setting among all config settings over the life of this contract
                     * @param signers ith element is address ith oracle uses to sign a report
                     * @param transmitters ith element is address ith oracle uses to transmit a report via the transmit method
                     * @param threshold maximum number of faulty/dishonest oracles the protocol can tolerate while still working correctly
                     * @param encodedConfigVersion version of the serialization format used for "encoded" parameter
                     * @param encoded serialized data used by oracles to configure their offchain operation
                     */
                    event ConfigSet(
                      uint32 previousConfigBlockNumber,
                      uint64 configCount,
                      address[] signers,
                      address[] transmitters,
                      uint8 threshold,
                      uint64 encodedConfigVersion,
                      bytes encoded
                    );
                    // Reverts transaction if config args are invalid
                    modifier checkConfigValid (
                      uint256 _numSigners, uint256 _numTransmitters, uint256 _threshold
                    ) {
                      require(_numSigners <= maxNumOracles, "too many signers");
                      require(_threshold > 0, "threshold must be positive");
                      require(
                        _numSigners == _numTransmitters,
                        "oracle addresses out of registration"
                      );
                      require(_numSigners > 3*_threshold, "faulty-oracle threshold too high");
                      _;
                    }
                    /**
                     * @notice sets offchain reporting protocol configuration incl. participating oracles
                     * @param _signers addresses with which oracles sign the reports
                     * @param _transmitters addresses oracles use to transmit the reports
                     * @param _threshold number of faulty oracles the system can tolerate
                     * @param _encodedConfigVersion version number for offchainEncoding schema
                     * @param _encoded encoded off-chain oracle configuration
                     */
                    function setConfig(
                      address[] calldata _signers,
                      address[] calldata _transmitters,
                      uint8 _threshold,
                      uint64 _encodedConfigVersion,
                      bytes calldata _encoded
                    )
                      external
                      checkConfigValid(_signers.length, _transmitters.length, _threshold)
                      onlyOwner()
                    {
                      while (s_signers.length != 0) { // remove any old signer/transmitter addresses
                        uint lastIdx = s_signers.length - 1;
                        address signer = s_signers[lastIdx];
                        address transmitter = s_transmitters[lastIdx];
                        payOracle(transmitter);
                        delete s_oracles[signer];
                        delete s_oracles[transmitter];
                        s_signers.pop();
                        s_transmitters.pop();
                      }
                      for (uint i = 0; i < _signers.length; i++) { // add new signer/transmitter addresses
                        require(
                          s_oracles[_signers[i]].role == Role.Unset,
                          "repeated signer address"
                        );
                        s_oracles[_signers[i]] = Oracle(uint8(i), Role.Signer);
                        require(s_payees[_transmitters[i]] != address(0), "payee must be set");
                        require(
                          s_oracles[_transmitters[i]].role == Role.Unset,
                          "repeated transmitter address"
                        );
                        s_oracles[_transmitters[i]] = Oracle(uint8(i), Role.Transmitter);
                        s_signers.push(_signers[i]);
                        s_transmitters.push(_transmitters[i]);
                      }
                      s_hotVars.threshold = _threshold;
                      uint32 previousConfigBlockNumber = s_latestConfigBlockNumber;
                      s_latestConfigBlockNumber = uint32(block.number);
                      s_configCount += 1;
                      uint64 configCount = s_configCount;
                      {
                        s_hotVars.latestConfigDigest = configDigestFromConfigData(
                          address(this),
                          configCount,
                          _signers,
                          _transmitters,
                          _threshold,
                          _encodedConfigVersion,
                          _encoded
                        );
                        s_hotVars.latestEpochAndRound = 0;
                      }
                      emit ConfigSet(
                        previousConfigBlockNumber,
                        configCount,
                        _signers,
                        _transmitters,
                        _threshold,
                        _encodedConfigVersion,
                        _encoded
                      );
                    }
                    function configDigestFromConfigData(
                      address _contractAddress,
                      uint64 _configCount,
                      address[] calldata _signers,
                      address[] calldata _transmitters,
                      uint8 _threshold,
                      uint64 _encodedConfigVersion,
                      bytes calldata _encodedConfig
                    ) internal pure returns (bytes16) {
                      return bytes16(keccak256(abi.encode(_contractAddress, _configCount,
                        _signers, _transmitters, _threshold, _encodedConfigVersion, _encodedConfig
                      )));
                    }
                    /**
                     * @notice information about current offchain reporting protocol configuration
                     * @return configCount ordinal number of current config, out of all configs applied to this contract so far
                     * @return blockNumber block at which this config was set
                     * @return configDigest domain-separation tag for current config (see configDigestFromConfigData)
                     */
                    function latestConfigDetails()
                      external
                      view
                      returns (
                        uint32 configCount,
                        uint32 blockNumber,
                        bytes16 configDigest
                      )
                    {
                      return (s_configCount, s_latestConfigBlockNumber, s_hotVars.latestConfigDigest);
                    }
                    /**
                     * @return list of addresses permitted to transmit reports to this contract
                     * @dev The list will match the order used to specify the transmitter during setConfig
                     */
                    function transmitters()
                      external
                      view
                      returns(address[] memory)
                    {
                        return s_transmitters;
                    }
                    /*
                     * On-chain validation logc
                     */
                    // Configuration for validator
                    struct ValidatorConfig {
                      AggregatorValidatorInterface validator;
                      uint32 gasLimit;
                    }
                    ValidatorConfig private s_validatorConfig;
                    /**
                     * @notice indicates that the validator configuration has been set
                     * @param previousValidator previous validator contract
                     * @param previousGasLimit previous gas limit for validate calls
                     * @param currentValidator current validator contract
                     * @param currentGasLimit current gas limit for validate calls
                     */
                    event ValidatorConfigSet(
                      AggregatorValidatorInterface indexed previousValidator,
                      uint32 previousGasLimit,
                      AggregatorValidatorInterface indexed currentValidator,
                      uint32 currentGasLimit
                    );
                    /**
                     * @notice validator configuration
                     * @return validator validator contract
                     * @return gasLimit gas limit for validate calls
                     */
                    function validatorConfig()
                      external
                      view
                      returns (AggregatorValidatorInterface validator, uint32 gasLimit)
                    {
                      ValidatorConfig memory vc = s_validatorConfig;
                      return (vc.validator, vc.gasLimit);
                    }
                    /**
                     * @notice sets validator configuration
                     * @dev set _newValidator to 0x0 to disable validate calls
                     * @param _newValidator address of the new validator contract
                     * @param _newGasLimit new gas limit for validate calls
                     */
                    function setValidatorConfig(AggregatorValidatorInterface _newValidator, uint32 _newGasLimit)
                      public
                      onlyOwner()
                    {
                      ValidatorConfig memory previous = s_validatorConfig;
                      if (previous.validator != _newValidator || previous.gasLimit != _newGasLimit) {
                        s_validatorConfig = ValidatorConfig({
                          validator: _newValidator,
                          gasLimit: _newGasLimit
                        });
                        emit ValidatorConfigSet(previous.validator, previous.gasLimit, _newValidator, _newGasLimit);
                      }
                    }
                    function validateAnswer(
                      uint32 _aggregatorRoundId,
                      int256 _answer
                    )
                      private
                    {
                      ValidatorConfig memory vc = s_validatorConfig;
                      if (address(vc.validator) == address(0)) {
                        return;
                      }
                      uint32 prevAggregatorRoundId = _aggregatorRoundId - 1;
                      int256 prevAggregatorRoundAnswer = s_transmissions[prevAggregatorRoundId].answer;
                      // We do not want the validator to ever prevent reporting, so we limit its
                      // gas usage and catch any errors that may arise.
                      try vc.validator.validate{gas: vc.gasLimit}(
                        prevAggregatorRoundId,
                        prevAggregatorRoundAnswer,
                        _aggregatorRoundId,
                        _answer
                      ) {} catch {}
                    }
                    /*
                     * requestNewRound logic
                     */
                    AccessControllerInterface internal s_requesterAccessController;
                    /**
                     * @notice emitted when a new requester access controller contract is set
                     * @param old the address prior to the current setting
                     * @param current the address of the new access controller contract
                     */
                    event RequesterAccessControllerSet(AccessControllerInterface old, AccessControllerInterface current);
                    /**
                     * @notice emitted to immediately request a new round
                     * @param requester the address of the requester
                     * @param configDigest the latest transmission's configDigest
                     * @param epoch the latest transmission's epoch
                     * @param round the latest transmission's round
                     */
                    event RoundRequested(address indexed requester, bytes16 configDigest, uint32 epoch, uint8 round);
                    /**
                     * @notice address of the requester access controller contract
                     * @return requester access controller address
                     */
                    function requesterAccessController()
                      external
                      view
                      returns (AccessControllerInterface)
                    {
                      return s_requesterAccessController;
                    }
                    /**
                     * @notice sets the requester access controller
                     * @param _requesterAccessController designates the address of the new requester access controller
                     */
                    function setRequesterAccessController(AccessControllerInterface _requesterAccessController)
                      public
                      onlyOwner()
                    {
                      AccessControllerInterface oldController = s_requesterAccessController;
                      if (_requesterAccessController != oldController) {
                        s_requesterAccessController = AccessControllerInterface(_requesterAccessController);
                        emit RequesterAccessControllerSet(oldController, _requesterAccessController);
                      }
                    }
                    /**
                     * @notice immediately requests a new round
                     * @return the aggregatorRoundId of the next round. Note: The report for this round may have been
                     * transmitted (but not yet mined) *before* requestNewRound() was even called. There is *no*
                     * guarantee of causality between the request and the report at aggregatorRoundId.
                     */
                    function requestNewRound() external returns (uint80) {
                      require(msg.sender == owner || s_requesterAccessController.hasAccess(msg.sender, msg.data),
                        "Only owner&requester can call");
                      HotVars memory hotVars = s_hotVars;
                      emit RoundRequested(
                        msg.sender,
                        hotVars.latestConfigDigest,
                        uint32(s_hotVars.latestEpochAndRound >> 8),
                        uint8(s_hotVars.latestEpochAndRound)
                      );
                      return hotVars.latestAggregatorRoundId + 1;
                    }
                    /*
                     * Transmission logic
                     */
                    /**
                     * @notice indicates that a new report was transmitted
                     * @param aggregatorRoundId the round to which this report was assigned
                     * @param answer median of the observations attached this report
                     * @param transmitter address from which the report was transmitted
                     * @param observations observations transmitted with this report
                     * @param rawReportContext signature-replay-prevention domain-separation tag
                     */
                    event NewTransmission(
                      uint32 indexed aggregatorRoundId,
                      int192 answer,
                      address transmitter,
                      int192[] observations,
                      bytes observers,
                      bytes32 rawReportContext
                    );
                    // decodeReport is used to check that the solidity and go code are using the
                    // same format. See TestOffchainAggregator.testDecodeReport and TestReportParsing
                    function decodeReport(bytes memory _report)
                      internal
                      pure
                      returns (
                        bytes32 rawReportContext,
                        bytes32 rawObservers,
                        int192[] memory observations
                      )
                    {
                      (rawReportContext, rawObservers, observations) = abi.decode(_report,
                        (bytes32, bytes32, int192[]));
                    }
                    // Used to relieve stack pressure in transmit
                    struct ReportData {
                      HotVars hotVars; // Only read from storage once
                      bytes observers; // ith element is the index of the ith observer
                      int192[] observations; // ith element is the ith observation
                      bytes vs; // jth element is the v component of the jth signature
                      bytes32 rawReportContext;
                    }
                    /*
                     * @notice details about the most recent report
                     * @return configDigest domain separation tag for the latest report
                     * @return epoch epoch in which the latest report was generated
                     * @return round OCR round in which the latest report was generated
                     * @return latestAnswer median value from latest report
                     * @return latestTimestamp when the latest report was transmitted
                     */
                    function latestTransmissionDetails()
                      external
                      view
                      returns (
                        bytes16 configDigest,
                        uint32 epoch,
                        uint8 round,
                        int192 latestAnswer,
                        uint64 latestTimestamp
                      )
                    {
                      require(msg.sender == tx.origin, "Only callable by EOA");
                      return (
                        s_hotVars.latestConfigDigest,
                        uint32(s_hotVars.latestEpochAndRound >> 8),
                        uint8(s_hotVars.latestEpochAndRound),
                        s_transmissions[s_hotVars.latestAggregatorRoundId].answer,
                        s_transmissions[s_hotVars.latestAggregatorRoundId].timestamp
                      );
                    }
                    // The constant-length components of the msg.data sent to transmit.
                    // See the "If we wanted to call sam" example on for example reasoning
                    // https://solidity.readthedocs.io/en/v0.7.2/abi-spec.html
                    uint16 private constant TRANSMIT_MSGDATA_CONSTANT_LENGTH_COMPONENT =
                      4 + // function selector
                      32 + // word containing start location of abiencoded _report value
                      32 + // word containing location start of abiencoded  _rs value
                      32 + // word containing start location of abiencoded _ss value
                      32 + // _rawVs value
                      32 + // word containing length of _report
                      32 + // word containing length _rs
                      32 + // word containing length of _ss
                      0; // placeholder
                    function expectedMsgDataLength(
                      bytes calldata _report, bytes32[] calldata _rs, bytes32[] calldata _ss
                    ) private pure returns (uint256 length)
                    {
                      // calldata will never be big enough to make this overflow
                      return uint256(TRANSMIT_MSGDATA_CONSTANT_LENGTH_COMPONENT) +
                        _report.length + // one byte pure entry in _report
                        _rs.length * 32 + // 32 bytes per entry in _rs
                        _ss.length * 32 + // 32 bytes per entry in _ss
                        0; // placeholder
                    }
                    /**
                     * @notice transmit is called to post a new report to the contract
                     * @param _report serialized report, which the signatures are signing. See parsing code below for format. The ith element of the observers component must be the index in s_signers of the address for the ith signature
                     * @param _rs ith element is the R components of the ith signature on report. Must have at most maxNumOracles entries
                     * @param _ss ith element is the S components of the ith signature on report. Must have at most maxNumOracles entries
                     * @param _rawVs ith element is the the V component of the ith signature
                     */
                    function transmit(
                      // NOTE: If these parameters are changed, expectedMsgDataLength and/or
                      // TRANSMIT_MSGDATA_CONSTANT_LENGTH_COMPONENT need to be changed accordingly
                      bytes calldata _report,
                      bytes32[] calldata _rs, bytes32[] calldata _ss, bytes32 _rawVs // signatures
                    )
                      external
                    {
                      uint256 initialGas = gasleft(); // This line must come first
                      // Make sure the transmit message-length matches the inputs. Otherwise, the
                      // transmitter could append an arbitrarily long (up to gas-block limit)
                      // string of 0 bytes, which we would reimburse at a rate of 16 gas/byte, but
                      // which would only cost the transmitter 4 gas/byte. (Appendix G of the
                      // yellow paper, p. 25, for G_txdatazero and EIP 2028 for G_txdatanonzero.)
                      // This could amount to reimbursement profit of 36 million gas, given a 3MB
                      // zero tail.
                      require(msg.data.length == expectedMsgDataLength(_report, _rs, _ss),
                        "transmit message too long");
                      ReportData memory r; // Relieves stack pressure
                      {
                        r.hotVars = s_hotVars; // cache read from storage
                        bytes32 rawObservers;
                        (r.rawReportContext, rawObservers, r.observations) = abi.decode(
                          _report, (bytes32, bytes32, int192[])
                        );
                        // rawReportContext consists of:
                        // 11-byte zero padding
                        // 16-byte configDigest
                        // 4-byte epoch
                        // 1-byte round
                        bytes16 configDigest = bytes16(r.rawReportContext << 88);
                        require(
                          r.hotVars.latestConfigDigest == configDigest,
                          "configDigest mismatch"
                        );
                        uint40 epochAndRound = uint40(uint256(r.rawReportContext));
                        // direct numerical comparison works here, because
                        //
                        //   ((e,r) <= (e',r')) implies (epochAndRound <= epochAndRound')
                        //
                        // because alphabetic ordering implies e <= e', and if e = e', then r<=r',
                        // so e*256+r <= e'*256+r', because r, r' < 256
                        require(r.hotVars.latestEpochAndRound < epochAndRound, "stale report");
                        require(_rs.length > r.hotVars.threshold, "not enough signatures");
                        require(_rs.length <= maxNumOracles, "too many signatures");
                        require(_ss.length == _rs.length, "signatures out of registration");
                        require(r.observations.length <= maxNumOracles,
                                "num observations out of bounds");
                        require(r.observations.length > 2 * r.hotVars.threshold,
                                "too few values to trust median");
                        // Copy signature parities in bytes32 _rawVs to bytes r.v
                        r.vs = new bytes(_rs.length);
                        for (uint8 i = 0; i < _rs.length; i++) {
                          r.vs[i] = _rawVs[i];
                        }
                        // Copy observer identities in bytes32 rawObservers to bytes r.observers
                        r.observers = new bytes(r.observations.length);
                        bool[maxNumOracles] memory seen;
                        for (uint8 i = 0; i < r.observations.length; i++) {
                          uint8 observerIdx = uint8(rawObservers[i]);
                          require(!seen[observerIdx], "observer index repeated");
                          seen[observerIdx] = true;
                          r.observers[i] = rawObservers[i];
                        }
                        Oracle memory transmitter = s_oracles[msg.sender];
                        require( // Check that sender is authorized to report
                          transmitter.role == Role.Transmitter &&
                          msg.sender == s_transmitters[transmitter.index],
                          "unauthorized transmitter"
                        );
                        // record epochAndRound here, so that we don't have to carry the local
                        // variable in transmit. The change is reverted if something fails later.
                        r.hotVars.latestEpochAndRound = epochAndRound;
                      }
                      { // Verify signatures attached to report
                        bytes32 h = keccak256(_report);
                        bool[maxNumOracles] memory signed;
                        Oracle memory o;
                        for (uint i = 0; i < _rs.length; i++) {
                          address signer = ecrecover(h, uint8(r.vs[i])+27, _rs[i], _ss[i]);
                          o = s_oracles[signer];
                          require(o.role == Role.Signer, "address not authorized to sign");
                          require(!signed[o.index], "non-unique signature");
                          signed[o.index] = true;
                        }
                      }
                      { // Check the report contents, and record the result
                        for (uint i = 0; i < r.observations.length - 1; i++) {
                          bool inOrder = r.observations[i] <= r.observations[i+1];
                          require(inOrder, "observations not sorted");
                        }
                        int192 median = r.observations[r.observations.length/2];
                        require(minAnswer <= median && median <= maxAnswer, "median is out of min-max range");
                        r.hotVars.latestAggregatorRoundId++;
                        s_transmissions[r.hotVars.latestAggregatorRoundId] =
                          Transmission(median, uint64(block.timestamp));
                        emit NewTransmission(
                          r.hotVars.latestAggregatorRoundId,
                          median,
                          msg.sender,
                          r.observations,
                          r.observers,
                          r.rawReportContext
                        );
                        // Emit these for backwards compatability with offchain consumers
                        // that only support legacy events
                        emit NewRound(
                          r.hotVars.latestAggregatorRoundId,
                          address(0x0), // use zero address since we don't have anybody "starting" the round here
                          block.timestamp
                        );
                        emit AnswerUpdated(
                          median,
                          r.hotVars.latestAggregatorRoundId,
                          block.timestamp
                        );
                        validateAnswer(r.hotVars.latestAggregatorRoundId, median);
                      }
                      s_hotVars = r.hotVars;
                      assert(initialGas < maxUint32);
                      reimburseAndRewardOracles(uint32(initialGas), r.observers);
                    }
                    /*
                     * v2 Aggregator interface
                     */
                    /**
                     * @notice median from the most recent report
                     */
                    function latestAnswer()
                      public
                      override
                      view
                      virtual
                      returns (int256)
                    {
                      return s_transmissions[s_hotVars.latestAggregatorRoundId].answer;
                    }
                    /**
                     * @notice timestamp of block in which last report was transmitted
                     */
                    function latestTimestamp()
                      public
                      override
                      view
                      virtual
                      returns (uint256)
                    {
                      return s_transmissions[s_hotVars.latestAggregatorRoundId].timestamp;
                    }
                    /**
                     * @notice Aggregator round (NOT OCR round) in which last report was transmitted
                     */
                    function latestRound()
                      public
                      override
                      view
                      virtual
                      returns (uint256)
                    {
                      return s_hotVars.latestAggregatorRoundId;
                    }
                    /**
                     * @notice median of report from given aggregator round (NOT OCR round)
                     * @param _roundId the aggregator round of the target report
                     */
                    function getAnswer(uint256 _roundId)
                      public
                      override
                      view
                      virtual
                      returns (int256)
                    {
                      if (_roundId > 0xFFFFFFFF) { return 0; }
                      return s_transmissions[uint32(_roundId)].answer;
                    }
                    /**
                     * @notice timestamp of block in which report from given aggregator round was transmitted
                     * @param _roundId aggregator round (NOT OCR round) of target report
                     */
                    function getTimestamp(uint256 _roundId)
                      public
                      override
                      view
                      virtual
                      returns (uint256)
                    {
                      if (_roundId > 0xFFFFFFFF) { return 0; }
                      return s_transmissions[uint32(_roundId)].timestamp;
                    }
                    /*
                     * v3 Aggregator interface
                     */
                    string constant private V3_NO_DATA_ERROR = "No data present";
                    /**
                     * @return answers are stored in fixed-point format, with this many digits of precision
                     */
                    uint8 immutable public override decimals;
                    /**
                     * @notice aggregator contract version
                     */
                    uint256 constant public override version = 4;
                    string internal s_description;
                    /**
                     * @notice human-readable description of observable this contract is reporting on
                     */
                    function description()
                      public
                      override
                      view
                      virtual
                      returns (string memory)
                    {
                      return s_description;
                    }
                    /**
                     * @notice details for the given aggregator round
                     * @param _roundId target aggregator round (NOT OCR round). Must fit in uint32
                     * @return roundId _roundId
                     * @return answer median of report from given _roundId
                     * @return startedAt timestamp of block in which report from given _roundId was transmitted
                     * @return updatedAt timestamp of block in which report from given _roundId was transmitted
                     * @return answeredInRound _roundId
                     */
                    function getRoundData(uint80 _roundId)
                      public
                      override
                      view
                      virtual
                      returns (
                        uint80 roundId,
                        int256 answer,
                        uint256 startedAt,
                        uint256 updatedAt,
                        uint80 answeredInRound
                      )
                    {
                      require(_roundId <= 0xFFFFFFFF, V3_NO_DATA_ERROR);
                      Transmission memory transmission = s_transmissions[uint32(_roundId)];
                      return (
                        _roundId,
                        transmission.answer,
                        transmission.timestamp,
                        transmission.timestamp,
                        _roundId
                      );
                    }
                    /**
                     * @notice aggregator details for the most recently transmitted report
                     * @return roundId aggregator round of latest report (NOT OCR round)
                     * @return answer median of latest report
                     * @return startedAt timestamp of block containing latest report
                     * @return updatedAt timestamp of block containing latest report
                     * @return answeredInRound aggregator round of latest report
                     */
                    function latestRoundData()
                      public
                      override
                      view
                      virtual
                      returns (
                        uint80 roundId,
                        int256 answer,
                        uint256 startedAt,
                        uint256 updatedAt,
                        uint80 answeredInRound
                      )
                    {
                      roundId = s_hotVars.latestAggregatorRoundId;
                      // Skipped for compatability with existing FluxAggregator in which latestRoundData never reverts.
                      // require(roundId != 0, V3_NO_DATA_ERROR);
                      Transmission memory transmission = s_transmissions[uint32(roundId)];
                      return (
                        roundId,
                        transmission.answer,
                        transmission.timestamp,
                        transmission.timestamp,
                        roundId
                      );
                    }
                  }
                  // SPDX-License-Identifier: MIT
                  pragma solidity ^0.7.1;
                  import "./SimpleWriteAccessController.sol";
                  /**
                   * @title SimpleReadAccessController
                   * @notice Gives access to:
                   * - any externally owned account (note that offchain actors can always read
                   * any contract storage regardless of onchain access control measures, so this
                   * does not weaken the access control while improving usability)
                   * - accounts explicitly added to an access list
                   * @dev SimpleReadAccessController is not suitable for access controlling writes
                   * since it grants any externally owned account access! See
                   * SimpleWriteAccessController for that.
                   */
                  contract SimpleReadAccessController is SimpleWriteAccessController {
                    /**
                     * @notice Returns the access of an address
                     * @param _user The address to query
                     */
                    function hasAccess(
                      address _user,
                      bytes memory _calldata
                    )
                      public
                      view
                      virtual
                      override
                      returns (bool)
                    {
                      return super.hasAccess(_user, _calldata) || _user == tx.origin;
                    }
                  }
                  // SPDX-License-Identifier: MIT
                  pragma solidity ^0.7.0;
                  interface AccessControllerInterface {
                    function hasAccess(address user, bytes calldata data) external view returns (bool);
                  }
                  // SPDX-License-Identifier: MIT
                  pragma solidity ^0.7.0;
                  import "./AggregatorInterface.sol";
                  import "./AggregatorV3Interface.sol";
                  interface AggregatorV2V3Interface is AggregatorInterface, AggregatorV3Interface
                  {
                  }// SPDX-License-Identifier: MIT
                  pragma solidity ^0.7.0;
                  interface AggregatorValidatorInterface {
                    function validate(
                      uint256 previousRoundId,
                      int256 previousAnswer,
                      uint256 currentRoundId,
                      int256 currentAnswer
                    ) external returns (bool);
                  }// SPDX-License-Identifier: MIT
                  pragma solidity ^0.7.1;
                  interface LinkTokenInterface {
                    function allowance(address owner, address spender) external view returns (uint256 remaining);
                    function approve(address spender, uint256 value) external returns (bool success);
                    function balanceOf(address owner) external view returns (uint256 balance);
                    function decimals() external view returns (uint8 decimalPlaces);
                    function decreaseApproval(address spender, uint256 addedValue) external returns (bool success);
                    function increaseApproval(address spender, uint256 subtractedValue) external;
                    function name() external view returns (string memory tokenName);
                    function symbol() external view returns (string memory tokenSymbol);
                    function totalSupply() external view returns (uint256 totalTokensIssued);
                    function transfer(address to, uint256 value) external returns (bool success);
                    function transferAndCall(address to, uint256 value, bytes calldata data) external returns (bool success);
                    function transferFrom(address from, address to, uint256 value) external returns (bool success);
                  }
                  // SPDX-License-Identifier: MIT
                  pragma solidity ^0.7.0;
                  /**
                   * @title The Owned contract
                   * @notice A contract with helpers for basic contract ownership.
                   */
                  contract Owned {
                    address payable public owner;
                    address private pendingOwner;
                    event OwnershipTransferRequested(
                      address indexed from,
                      address indexed to
                    );
                    event OwnershipTransferred(
                      address indexed from,
                      address indexed to
                    );
                    constructor() {
                      owner = msg.sender;
                    }
                    /**
                     * @dev Allows an owner to begin transferring ownership to a new address,
                     * pending.
                     */
                    function transferOwnership(address _to)
                      external
                      onlyOwner()
                    {
                      pendingOwner = _to;
                      emit OwnershipTransferRequested(owner, _to);
                    }
                    /**
                     * @dev Allows an ownership transfer to be completed by the recipient.
                     */
                    function acceptOwnership()
                      external
                    {
                      require(msg.sender == pendingOwner, "Must be proposed owner");
                      address oldOwner = owner;
                      owner = msg.sender;
                      pendingOwner = address(0);
                      emit OwnershipTransferred(oldOwner, msg.sender);
                    }
                    /**
                     * @dev Reverts if called by anyone other than the contract owner.
                     */
                    modifier onlyOwner() {
                      require(msg.sender == owner, "Only callable by owner");
                      _;
                    }
                  }
                  // SPDX-License-Identifier: MIT
                  pragma solidity ^0.7.0;
                  import "./AccessControllerInterface.sol";
                  import "./LinkTokenInterface.sol";
                  import "./Owned.sol";
                  /**
                   * @notice tracks administration of oracle-reward and gas-reimbursement parameters.
                   * @dev
                   * If you read or change this, be sure to read or adjust the comments. They
                   * track the units of the values under consideration, and are crucial to
                   * the readability of the operations it specifies.
                   * @notice
                   * Trust Model:
                   * Nothing in this contract prevents a billing admin from setting insane
                   * values for the billing parameters in setBilling. Oracles
                   * participating in this contract should regularly check that the
                   * parameters make sense. Similarly, the outstanding obligations of this
                   * contract to the oracles can exceed the funds held by the contract.
                   * Oracles participating in this contract should regularly check that it
                   * holds sufficient funds and stop interacting with it if funding runs
                   * out.
                   * This still leaves oracles with some risk due to TOCTOU issues.
                   * However, since the sums involved are pretty small (Ethereum
                   * transactions aren't that expensive in the end) and an oracle would
                   * likely stop participating in a contract it repeatedly lost money on,
                   * this risk is deemed acceptable. Oracles should also regularly
                   * withdraw any funds in the contract to prevent issues where the
                   * contract becomes underfunded at a later time, and different oracles
                   * are competing for the left-over funds.
                   * Finally, note that any change to the set of oracles or to the billing
                   * parameters will trigger payout of all oracles first (using the old
                   * parameters), a billing admin cannot take away funds that are already
                   * marked for payment.
                  */
                  contract OffchainAggregatorBilling is Owned {
                    // Maximum number of oracles the offchain reporting protocol is designed for
                    uint256 constant internal maxNumOracles = 31;
                    // Parameters for oracle payments
                    struct Billing {
                      // Highest compensated gas price, in ETH-gwei uints
                      uint32 maximumGasPrice;
                      // If gas price is less (in ETH-gwei units), transmitter gets half the savings
                      uint32 reasonableGasPrice;
                      // Pay transmitter back this much LINK per unit eth spent on gas
                      // (1e-6LINK/ETH units)
                      uint32 microLinkPerEth;
                      // Fixed LINK reward for each observer, in LINK-gwei units
                      uint32 linkGweiPerObservation;
                      // Fixed reward for transmitter, in linkGweiPerObservation units
                      uint32 linkGweiPerTransmission;
                    }
                    Billing internal s_billing;
                    /**
                    * @return LINK token contract used for billing
                    */
                    LinkTokenInterface immutable public LINK;
                    AccessControllerInterface internal s_billingAccessController;
                    // ith element is number of observation rewards due to ith process, plus one.
                    // This is expected to saturate after an oracle has submitted 65,535
                    // observations, or about 65535/(3*24*20) = 45 days, given a transmission
                    // every 3 minutes.
                    //
                    // This is always one greater than the actual value, so that when the value is
                    // reset to zero, we don't end up with a zero value in storage (which would
                    // result in a higher gas cost, the next time the value is incremented.)
                    // Calculations using this variable need to take that offset into account.
                    uint16[maxNumOracles] internal s_oracleObservationsCounts;
                    // Addresses at which oracles want to receive payments, by transmitter address
                    mapping (address /* transmitter */ => address /* payment address */)
                      internal
                      s_payees;
                    // Payee addresses which must be approved by the owner
                    mapping (address /* transmitter */ => address /* payment address */)
                      internal
                      s_proposedPayees;
                    // LINK-wei-denominated reimbursements for gas used by transmitters.
                    //
                    // This is always one greater than the actual value, so that when the value is
                    // reset to zero, we don't end up with a zero value in storage (which would
                    // result in a higher gas cost, the next time the value is incremented.)
                    // Calculations using this variable need to take that offset into account.
                    //
                    // Argument for overflow safety:
                    // We have the following maximum intermediate values:
                    // - 2**40 additions to this variable (epochAndRound is a uint40)
                    // - 2**32 gas price in ethgwei/gas
                    // - 1e9 ethwei/ethgwei
                    // - 2**32 gas since the block gas limit is at ~20 million
                    // - 2**32 (microlink/eth)
                    // And we have 2**40 * 2**32 * 1e9 * 2**32 * 2**32 < 2**166
                    // (we also divide in some places, but that only makes the value smaller)
                    // We can thus safely use uint256 intermediate values for the computation
                    // updating this variable.
                    uint256[maxNumOracles] internal s_gasReimbursementsLinkWei;
                    // Used for s_oracles[a].role, where a is an address, to track the purpose
                    // of the address, or to indicate that the address is unset.
                    enum Role {
                      // No oracle role has been set for address a
                      Unset,
                      // Signing address for the s_oracles[a].index'th oracle. I.e., report
                      // signatures from this oracle should ecrecover back to address a.
                      Signer,
                      // Transmission address for the s_oracles[a].index'th oracle. I.e., if a
                      // report is received by OffchainAggregator.transmit in which msg.sender is
                      // a, it is attributed to the s_oracles[a].index'th oracle.
                      Transmitter
                    }
                    struct Oracle {
                      uint8 index; // Index of oracle in s_signers/s_transmitters
                      Role role;   // Role of the address which mapped to this struct
                    }
                    mapping (address /* signer OR transmitter address */ => Oracle)
                      internal s_oracles;
                    // s_signers contains the signing address of each oracle
                    address[] internal s_signers;
                    // s_transmitters contains the transmission address of each oracle,
                    // i.e. the address the oracle actually sends transactions to the contract from
                    address[] internal s_transmitters;
                    uint256 constant private  maxUint16 = (1 << 16) - 1;
                    uint256 constant internal maxUint128 = (1 << 128) - 1;
                    constructor(
                      uint32 _maximumGasPrice,
                      uint32 _reasonableGasPrice,
                      uint32 _microLinkPerEth,
                      uint32 _linkGweiPerObservation,
                      uint32 _linkGweiPerTransmission,
                      address _link,
                      AccessControllerInterface _billingAccessController
                    )
                    {
                      setBillingInternal(_maximumGasPrice, _reasonableGasPrice, _microLinkPerEth,
                        _linkGweiPerObservation, _linkGweiPerTransmission);
                      setBillingAccessControllerInternal(_billingAccessController);
                      LINK = LinkTokenInterface(_link);
                      uint16[maxNumOracles] memory counts; // See s_oracleObservationsCounts docstring
                      uint256[maxNumOracles] memory gas; // see s_gasReimbursementsLinkWei docstring
                      for (uint8 i = 0; i < maxNumOracles; i++) {
                        counts[i] = 1;
                        gas[i] = 1;
                      }
                      s_oracleObservationsCounts = counts;
                      s_gasReimbursementsLinkWei = gas;
                    }
                    /**
                     * @notice emitted when billing parameters are set
                     * @param maximumGasPrice highest gas price for which transmitter will be compensated
                     * @param reasonableGasPrice transmitter will receive reward for gas prices under this value
                     * @param microLinkPerEth reimbursement per ETH of gas cost, in 1e-6LINK units
                     * @param linkGweiPerObservation reward to oracle for contributing an observation to a successfully transmitted report, in 1e-9LINK units
                     * @param linkGweiPerTransmission reward to transmitter of a successful report, in 1e-9LINK units
                     */
                    event BillingSet(
                      uint32 maximumGasPrice,
                      uint32 reasonableGasPrice,
                      uint32 microLinkPerEth,
                      uint32 linkGweiPerObservation,
                      uint32 linkGweiPerTransmission
                    );
                    function setBillingInternal(
                      uint32 _maximumGasPrice,
                      uint32 _reasonableGasPrice,
                      uint32 _microLinkPerEth,
                      uint32 _linkGweiPerObservation,
                      uint32 _linkGweiPerTransmission
                    )
                      internal
                    {
                      s_billing = Billing(_maximumGasPrice, _reasonableGasPrice, _microLinkPerEth,
                        _linkGweiPerObservation, _linkGweiPerTransmission);
                      emit BillingSet(_maximumGasPrice, _reasonableGasPrice, _microLinkPerEth,
                        _linkGweiPerObservation, _linkGweiPerTransmission);
                    }
                    /**
                     * @notice sets billing parameters
                     * @param _maximumGasPrice highest gas price for which transmitter will be compensated
                     * @param _reasonableGasPrice transmitter will receive reward for gas prices under this value
                     * @param _microLinkPerEth reimbursement per ETH of gas cost, in 1e-6LINK units
                     * @param _linkGweiPerObservation reward to oracle for contributing an observation to a successfully transmitted report, in 1e-9LINK units
                     * @param _linkGweiPerTransmission reward to transmitter of a successful report, in 1e-9LINK units
                     * @dev access control provided by billingAccessController
                     */
                    function setBilling(
                      uint32 _maximumGasPrice,
                      uint32 _reasonableGasPrice,
                      uint32 _microLinkPerEth,
                      uint32 _linkGweiPerObservation,
                      uint32 _linkGweiPerTransmission
                    )
                      external
                    {
                      AccessControllerInterface access = s_billingAccessController;
                      require(msg.sender == owner || access.hasAccess(msg.sender, msg.data),
                        "Only owner&billingAdmin can call");
                      payOracles();
                      setBillingInternal(_maximumGasPrice, _reasonableGasPrice, _microLinkPerEth,
                        _linkGweiPerObservation, _linkGweiPerTransmission);
                    }
                    /**
                     * @notice gets billing parameters
                     * @param maximumGasPrice highest gas price for which transmitter will be compensated
                     * @param reasonableGasPrice transmitter will receive reward for gas prices under this value
                     * @param microLinkPerEth reimbursement per ETH of gas cost, in 1e-6LINK units
                     * @param linkGweiPerObservation reward to oracle for contributing an observation to a successfully transmitted report, in 1e-9LINK units
                     * @param linkGweiPerTransmission reward to transmitter of a successful report, in 1e-9LINK units
                     */
                    function getBilling()
                      external
                      view
                      returns (
                        uint32 maximumGasPrice,
                        uint32 reasonableGasPrice,
                        uint32 microLinkPerEth,
                        uint32 linkGweiPerObservation,
                        uint32 linkGweiPerTransmission
                      )
                    {
                      Billing memory billing = s_billing;
                      return (
                        billing.maximumGasPrice,
                        billing.reasonableGasPrice,
                        billing.microLinkPerEth,
                        billing.linkGweiPerObservation,
                        billing.linkGweiPerTransmission
                      );
                    }
                    /**
                     * @notice emitted when a new access-control contract is set
                     * @param old the address prior to the current setting
                     * @param current the address of the new access-control contract
                     */
                    event BillingAccessControllerSet(AccessControllerInterface old, AccessControllerInterface current);
                    function setBillingAccessControllerInternal(AccessControllerInterface _billingAccessController)
                      internal
                    {
                      AccessControllerInterface oldController = s_billingAccessController;
                      if (_billingAccessController != oldController) {
                        s_billingAccessController = _billingAccessController;
                        emit BillingAccessControllerSet(
                          oldController,
                          _billingAccessController
                        );
                      }
                    }
                    /**
                     * @notice sets billingAccessController
                     * @param _billingAccessController new billingAccessController contract address
                     * @dev only owner can call this
                     */
                    function setBillingAccessController(AccessControllerInterface _billingAccessController)
                      external
                      onlyOwner
                    {
                      setBillingAccessControllerInternal(_billingAccessController);
                    }
                    /**
                     * @notice gets billingAccessController
                     * @return address of billingAccessController contract
                     */
                    function billingAccessController()
                      external
                      view
                      returns (AccessControllerInterface)
                    {
                      return s_billingAccessController;
                    }
                    /**
                     * @notice withdraws an oracle's payment from the contract
                     * @param _transmitter the transmitter address of the oracle
                     * @dev must be called by oracle's payee address
                     */
                    function withdrawPayment(address _transmitter)
                      external
                    {
                      require(msg.sender == s_payees[_transmitter], "Only payee can withdraw");
                      payOracle(_transmitter);
                    }
                    /**
                     * @notice query an oracle's payment amount
                     * @param _transmitter the transmitter address of the oracle
                     */
                    function owedPayment(address _transmitter)
                      public
                      view
                      returns (uint256)
                    {
                      Oracle memory oracle = s_oracles[_transmitter];
                      if (oracle.role == Role.Unset) { return 0; }
                      Billing memory billing = s_billing;
                      uint256 linkWeiAmount =
                        uint256(s_oracleObservationsCounts[oracle.index] - 1) *
                        uint256(billing.linkGweiPerObservation) *
                        (1 gwei);
                      linkWeiAmount += s_gasReimbursementsLinkWei[oracle.index] - 1;
                      return linkWeiAmount;
                    }
                    /**
                     * @notice emitted when an oracle has been paid LINK
                     * @param transmitter address from which the oracle sends reports to the transmit method
                     * @param payee address to which the payment is sent
                     * @param amount amount of LINK sent
                     */
                    event OraclePaid(address transmitter, address payee, uint256 amount);
                    // payOracle pays out _transmitter's balance to the corresponding payee, and zeros it out
                    function payOracle(address _transmitter)
                      internal
                    {
                      Oracle memory oracle = s_oracles[_transmitter];
                      uint256 linkWeiAmount = owedPayment(_transmitter);
                      if (linkWeiAmount > 0) {
                        address payee = s_payees[_transmitter];
                        // Poses no re-entrancy issues, because LINK.transfer does not yield
                        // control flow.
                        require(LINK.transfer(payee, linkWeiAmount), "insufficient funds");
                        s_oracleObservationsCounts[oracle.index] = 1; // "zero" the counts. see var's docstring
                        s_gasReimbursementsLinkWei[oracle.index] = 1; // "zero" the counts. see var's docstring
                        emit OraclePaid(_transmitter, payee, linkWeiAmount);
                      }
                    }
                    // payOracles pays out all transmitters, and zeros out their balances.
                    //
                    // It's much more gas-efficient to do this as a single operation, to avoid
                    // hitting storage too much.
                    function payOracles()
                      internal
                    {
                      Billing memory billing = s_billing;
                      uint16[maxNumOracles] memory observationsCounts = s_oracleObservationsCounts;
                      uint256[maxNumOracles] memory gasReimbursementsLinkWei =
                        s_gasReimbursementsLinkWei;
                      address[] memory transmitters = s_transmitters;
                      for (uint transmitteridx = 0; transmitteridx < transmitters.length; transmitteridx++) {
                        uint256 reimbursementAmountLinkWei = gasReimbursementsLinkWei[transmitteridx] - 1;
                        uint256 obsCount = observationsCounts[transmitteridx] - 1;
                        uint256 linkWeiAmount =
                          obsCount * uint256(billing.linkGweiPerObservation) * (1 gwei) + reimbursementAmountLinkWei;
                        if (linkWeiAmount > 0) {
                            address payee = s_payees[transmitters[transmitteridx]];
                            // Poses no re-entrancy issues, because LINK.transfer does not yield
                            // control flow.
                            require(LINK.transfer(payee, linkWeiAmount), "insufficient funds");
                            observationsCounts[transmitteridx] = 1;       // "zero" the counts.
                            gasReimbursementsLinkWei[transmitteridx] = 1; // "zero" the counts.
                            emit OraclePaid(transmitters[transmitteridx], payee, linkWeiAmount);
                          }
                      }
                      // "Zero" the accounting storage variables
                      s_oracleObservationsCounts = observationsCounts;
                      s_gasReimbursementsLinkWei = gasReimbursementsLinkWei;
                    }
                    function oracleRewards(
                      bytes memory observers,
                      uint16[maxNumOracles] memory observations
                    )
                      internal
                      pure
                      returns (uint16[maxNumOracles] memory)
                    {
                      // reward each observer-participant with the observer reward
                      for (uint obsIdx = 0; obsIdx < observers.length; obsIdx++) {
                        uint8 observer = uint8(observers[obsIdx]);
                        observations[observer] = saturatingAddUint16(observations[observer], 1);
                      }
                      return observations;
                    }
                    // This value needs to change if maxNumOracles is increased, or the accounting
                    // calculations at the bottom of reimburseAndRewardOracles change.
                    //
                    // To recalculate it, run the profiler as described in
                    // ../../profile/README.md, and add up the gas-usage values reported for the
                    // lines in reimburseAndRewardOracles following the "gasLeft = gasleft()"
                    // line. E.g., you will see output like this:
                    //
                    //      7        uint256 gasLeft = gasleft();
                    //     29        uint256 gasCostEthWei = transmitterGasCostEthWei(
                    //      9          uint256(initialGas),
                    //      3          gasPrice,
                    //      3          callDataGasCost,
                    //      3          gasLeft
                    //      .
                    //      .
                    //      .
                    //     59        uint256 gasCostLinkWei = (gasCostEthWei * billing.microLinkPerEth)/ 1e6;
                    //      .
                    //      .
                    //      .
                    //   5047        s_gasReimbursementsLinkWei[txOracle.index] =
                    //    856          s_gasReimbursementsLinkWei[txOracle.index] + gasCostLinkWei +
                    //     26          uint256(billing.linkGweiPerTransmission) * (1 gwei);
                    //
                    // If those were the only lines to be accounted for, you would add up
                    // 29+9+3+3+3+59+5047+856+26=6035.
                    uint256 internal constant accountingGasCost = 6035;
                    // Uncomment the following declaration to compute the remaining gas cost after
                    // above gasleft(). (This must exist in a base class to OffchainAggregator, so
                    // it can't go in TestOffchainAggregator.)
                    //
                    // uint256 public gasUsedInAccounting;
                    // Gas price at which the transmitter should be reimbursed, in ETH-gwei/gas
                    function impliedGasPrice(
                      uint256 txGasPrice,         // ETH-gwei/gas units
                      uint256 reasonableGasPrice, // ETH-gwei/gas units
                      uint256 maximumGasPrice     // ETH-gwei/gas units
                    )
                      internal
                      pure
                      returns (uint256)
                    {
                      // Reward the transmitter for choosing an efficient gas price: if they manage
                      // to come in lower than considered reasonable, give them half the savings.
                      //
                      // The following calculations are all in units of gwei/gas, i.e. 1e-9ETH/gas
                      uint256 gasPrice = txGasPrice;
                      if (txGasPrice < reasonableGasPrice) {
                        // Give transmitter half the savings for coming in under the reasonable gas price
                        gasPrice += (reasonableGasPrice - txGasPrice) / 2;
                      }
                      // Don't reimburse a gas price higher than maximumGasPrice
                      return min(gasPrice, maximumGasPrice);
                    }
                    // gas reimbursement due the transmitter, in ETH-wei
                    //
                    // If this function is changed, accountingGasCost needs to change, too. See
                    // its docstring
                    function transmitterGasCostEthWei(
                      uint256 initialGas,
                      uint256 gasPrice, // ETH-gwei/gas units
                      uint256 callDataCost, // gas units
                      uint256 gasLeft
                    )
                      internal
                      pure
                      returns (uint128 gasCostEthWei)
                    {
                      require(initialGas >= gasLeft, "gasLeft cannot exceed initialGas");
                      uint256 gasUsed = // gas units
                        initialGas - gasLeft + // observed gas usage
                        callDataCost + accountingGasCost; // estimated gas usage
                      // gasUsed is in gas units, gasPrice is in ETH-gwei/gas units; convert to ETH-wei
                      uint256 fullGasCostEthWei = gasUsed * gasPrice * (1 gwei);
                      assert(fullGasCostEthWei < maxUint128); // the entire ETH supply fits in a uint128...
                      return uint128(fullGasCostEthWei);
                    }
                    /**
                     * @notice withdraw any available funds left in the contract, up to _amount, after accounting for the funds due to participants in past reports
                     * @param _recipient address to send funds to
                     * @param _amount maximum amount to withdraw, denominated in LINK-wei.
                     * @dev access control provided by billingAccessController
                     */
                    function withdrawFunds(address _recipient, uint256 _amount)
                      external
                    {
                      require(msg.sender == owner || s_billingAccessController.hasAccess(msg.sender, msg.data),
                        "Only owner&billingAdmin can call");
                      uint256 linkDue = totalLINKDue();
                      uint256 linkBalance = LINK.balanceOf(address(this));
                      require(linkBalance >= linkDue, "insufficient balance");
                      require(LINK.transfer(_recipient, min(linkBalance - linkDue, _amount)), "insufficient funds");
                    }
                    // Total LINK due to participants in past reports.
                    function totalLINKDue()
                      internal
                      view
                      returns (uint256 linkDue)
                    {
                      // Argument for overflow safety: We do all computations in
                      // uint256s. The inputs to linkDue are:
                      // - the <= 31 observation rewards each of which has less than
                      //   64 bits (32 bits for billing.linkGweiPerObservation, 32 bits
                      //   for wei/gwei conversion). Hence 69 bits are sufficient for this part.
                      // - the <= 31 gas reimbursements, each of which consists of at most 166
                      //   bits (see s_gasReimbursementsLinkWei docstring). Hence 171 bits are
                      //   sufficient for this part
                      // In total, 172 bits are enough.
                      uint16[maxNumOracles] memory observationCounts = s_oracleObservationsCounts;
                      for (uint i = 0; i < maxNumOracles; i++) {
                        linkDue += observationCounts[i] - 1; // Stored value is one greater than actual value
                      }
                      Billing memory billing = s_billing;
                      // Convert linkGweiPerObservation to uint256, or this overflows!
                      linkDue *= uint256(billing.linkGweiPerObservation) * (1 gwei);
                      address[] memory transmitters = s_transmitters;
                      uint256[maxNumOracles] memory gasReimbursementsLinkWei =
                        s_gasReimbursementsLinkWei;
                      for (uint i = 0; i < transmitters.length; i++) {
                        linkDue += uint256(gasReimbursementsLinkWei[i]-1); // Stored value is one greater than actual value
                      }
                    }
                    /**
                     * @notice allows oracles to check that sufficient LINK balance is available
                     * @return availableBalance LINK available on this contract, after accounting for outstanding obligations. can become negative
                     */
                    function linkAvailableForPayment()
                      external
                      view
                      returns (int256 availableBalance)
                    {
                      // there are at most one billion LINK, so this cast is safe
                      int256 balance = int256(LINK.balanceOf(address(this)));
                      // according to the argument in the definition of totalLINKDue,
                      // totalLINKDue is never greater than 2**172, so this cast is safe
                      int256 due = int256(totalLINKDue());
                      // safe from overflow according to above sizes
                      return int256(balance) - int256(due);
                    }
                    /**
                     * @notice number of observations oracle is due to be reimbursed for
                     * @param _signerOrTransmitter address used by oracle for signing or transmitting reports
                     */
                    function oracleObservationCount(address _signerOrTransmitter)
                      external
                      view
                      returns (uint16)
                    {
                      Oracle memory oracle = s_oracles[_signerOrTransmitter];
                      if (oracle.role == Role.Unset) { return 0; }
                      return s_oracleObservationsCounts[oracle.index] - 1;
                    }
                    function reimburseAndRewardOracles(
                      uint32 initialGas,
                      bytes memory observers
                    )
                      internal
                    {
                      Oracle memory txOracle = s_oracles[msg.sender];
                      Billing memory billing = s_billing;
                      // Reward oracles for providing observations. Oracles are not rewarded
                      // for providing signatures, because signing is essentially free.
                      s_oracleObservationsCounts =
                        oracleRewards(observers, s_oracleObservationsCounts);
                      // Reimburse transmitter of the report for gas usage
                      require(txOracle.role == Role.Transmitter,
                        "sent by undesignated transmitter"
                      );
                      uint256 gasPrice = impliedGasPrice(
                        tx.gasprice / (1 gwei), // convert to ETH-gwei units
                        billing.reasonableGasPrice,
                        billing.maximumGasPrice
                      );
                      // The following is only an upper bound, as it ignores the cheaper cost for
                      // 0 bytes. Safe from overflow, because calldata just isn't that long.
                      uint256 callDataGasCost = 16 * msg.data.length;
                      // If any changes are made to subsequent calculations, accountingGasCost
                      // needs to change, too.
                      uint256 gasLeft = gasleft();
                      uint256 gasCostEthWei = transmitterGasCostEthWei(
                        uint256(initialGas),
                        gasPrice,
                        callDataGasCost,
                        gasLeft
                      );
                      // microLinkPerEth is 1e-6LINK/ETH units, gasCostEthWei is 1e-18ETH units
                      // (ETH-wei), product is 1e-24LINK-wei units, dividing by 1e6 gives
                      // 1e-18LINK units, i.e. LINK-wei units
                      // Safe from over/underflow, since all components are non-negative,
                      // gasCostEthWei will always fit into uint128 and microLinkPerEth is a
                      // uint32 (128+32 < 256!).
                      uint256 gasCostLinkWei = (gasCostEthWei * billing.microLinkPerEth)/ 1e6;
                      // Safe from overflow, because gasCostLinkWei < 2**160 and
                      // billing.linkGweiPerTransmission * (1 gwei) < 2**64 and we increment
                      // s_gasReimbursementsLinkWei[txOracle.index] at most 2**40 times.
                      s_gasReimbursementsLinkWei[txOracle.index] =
                        s_gasReimbursementsLinkWei[txOracle.index] + gasCostLinkWei +
                        uint256(billing.linkGweiPerTransmission) * (1 gwei); // convert from linkGwei to linkWei
                      // Uncomment next line to compute the remaining gas cost after above gasleft().
                      // See OffchainAggregatorBilling.accountingGasCost docstring for more information.
                      //
                      // gasUsedInAccounting = gasLeft - gasleft();
                    }
                    /*
                     * Payee management
                     */
                    /**
                     * @notice emitted when a transfer of an oracle's payee address has been initiated
                     * @param transmitter address from which the oracle sends reports to the transmit method
                     * @param current the payeee address for the oracle, prior to this setting
                     * @param proposed the proposed new payee address for the oracle
                     */
                    event PayeeshipTransferRequested(
                      address indexed transmitter,
                      address indexed current,
                      address indexed proposed
                    );
                    /**
                     * @notice emitted when a transfer of an oracle's payee address has been completed
                     * @param transmitter address from which the oracle sends reports to the transmit method
                     * @param current the payeee address for the oracle, prior to this setting
                     */
                    event PayeeshipTransferred(
                      address indexed transmitter,
                      address indexed previous,
                      address indexed current
                    );
                    /**
                     * @notice sets the payees for transmitting addresses
                     * @param _transmitters addresses oracles use to transmit the reports
                     * @param _payees addresses of payees corresponding to list of transmitters
                     * @dev must be called by owner
                     * @dev cannot be used to change payee addresses, only to initially populate them
                     */
                    function setPayees(
                      address[] calldata _transmitters,
                      address[] calldata _payees
                    )
                      external
                      onlyOwner()
                    {
                      require(_transmitters.length == _payees.length, "transmitters.size != payees.size");
                      for (uint i = 0; i < _transmitters.length; i++) {
                        address transmitter = _transmitters[i];
                        address payee = _payees[i];
                        address currentPayee = s_payees[transmitter];
                        bool zeroedOut = currentPayee == address(0);
                        require(zeroedOut || currentPayee == payee, "payee already set");
                        s_payees[transmitter] = payee;
                        if (currentPayee != payee) {
                          emit PayeeshipTransferred(transmitter, currentPayee, payee);
                        }
                      }
                    }
                    /**
                     * @notice first step of payeeship transfer (safe transfer pattern)
                     * @param _transmitter transmitter address of oracle whose payee is changing
                     * @param _proposed new payee address
                     * @dev can only be called by payee address
                     */
                    function transferPayeeship(
                      address _transmitter,
                      address _proposed
                    )
                      external
                    {
                        require(msg.sender == s_payees[_transmitter], "only current payee can update");
                        require(msg.sender != _proposed, "cannot transfer to self");
                        address previousProposed = s_proposedPayees[_transmitter];
                        s_proposedPayees[_transmitter] = _proposed;
                        if (previousProposed != _proposed) {
                          emit PayeeshipTransferRequested(_transmitter, msg.sender, _proposed);
                        }
                    }
                    /**
                     * @notice second step of payeeship transfer (safe transfer pattern)
                     * @param _transmitter transmitter address of oracle whose payee is changing
                     * @dev can only be called by proposed new payee address
                     */
                    function acceptPayeeship(
                      address _transmitter
                    )
                      external
                    {
                      require(msg.sender == s_proposedPayees[_transmitter], "only proposed payees can accept");
                      address currentPayee = s_payees[_transmitter];
                      s_payees[_transmitter] = msg.sender;
                      s_proposedPayees[_transmitter] = address(0);
                      emit PayeeshipTransferred(_transmitter, currentPayee, msg.sender);
                    }
                    /*
                     * Helper functions
                     */
                    function saturatingAddUint16(uint16 _x, uint16 _y)
                      internal
                      pure
                      returns (uint16)
                    {
                      return uint16(min(uint256(_x)+uint256(_y), maxUint16));
                    }
                    function min(uint256 a, uint256 b)
                      internal
                      pure
                      returns (uint256)
                    {
                      if (a < b) { return a; }
                      return b;
                    }
                  }
                  // SPDX-License-Identifier: MIT
                  pragma solidity ^0.7.0;
                  abstract contract TypeAndVersionInterface{
                    function typeAndVersion()
                      external
                      pure
                      virtual
                      returns (string memory);
                  }// SPDX-License-Identifier: MIT
                  pragma solidity ^0.7.0;
                  interface AggregatorInterface {
                    function latestAnswer() external view returns (int256);
                    function latestTimestamp() external view returns (uint256);
                    function latestRound() external view returns (uint256);
                    function getAnswer(uint256 roundId) external view returns (int256);
                    function getTimestamp(uint256 roundId) external view returns (uint256);
                    event AnswerUpdated(int256 indexed current, uint256 indexed roundId, uint256 updatedAt);
                    event NewRound(uint256 indexed roundId, address indexed startedBy, uint256 startedAt);
                  }
                  // SPDX-License-Identifier: MIT
                  pragma solidity ^0.7.0;
                  interface AggregatorV3Interface {
                    function decimals() external view returns (uint8);
                    function description() external view returns (string memory);
                    function version() external view returns (uint256);
                    // getRoundData and latestRoundData should both raise "No data present"
                    // if they do not have data to report, instead of returning unset values
                    // which could be misinterpreted as actual reported values.
                    function getRoundData(uint80 _roundId)
                      external
                      view
                      returns (
                        uint80 roundId,
                        int256 answer,
                        uint256 startedAt,
                        uint256 updatedAt,
                        uint80 answeredInRound
                      );
                    function latestRoundData()
                      external
                      view
                      returns (
                        uint80 roundId,
                        int256 answer,
                        uint256 startedAt,
                        uint256 updatedAt,
                        uint80 answeredInRound
                      );
                  }
                  // SPDX-License-Identifier: MIT
                  pragma solidity ^0.7.0;
                  import "./Owned.sol";
                  import "./AccessControllerInterface.sol";
                  /**
                   * @title SimpleWriteAccessController
                   * @notice Gives access to accounts explicitly added to an access list by the
                   * controller's owner.
                   * @dev does not make any special permissions for externally, see
                   * SimpleReadAccessController for that.
                   */
                  contract SimpleWriteAccessController is AccessControllerInterface, Owned {
                    bool public checkEnabled;
                    mapping(address => bool) internal accessList;
                    event AddedAccess(address user);
                    event RemovedAccess(address user);
                    event CheckAccessEnabled();
                    event CheckAccessDisabled();
                    constructor()
                    {
                      checkEnabled = true;
                    }
                    /**
                     * @notice Returns the access of an address
                     * @param _user The address to query
                     */
                    function hasAccess(
                      address _user,
                      bytes memory
                    )
                      public
                      view
                      virtual
                      override
                      returns (bool)
                    {
                      return accessList[_user] || !checkEnabled;
                    }
                    /**
                     * @notice Adds an address to the access list
                     * @param _user The address to add
                     */
                    function addAccess(address _user) external onlyOwner() {
                      addAccessInternal(_user);
                    }
                    function addAccessInternal(address _user) internal {
                      if (!accessList[_user]) {
                        accessList[_user] = true;
                        emit AddedAccess(_user);
                      }
                    }
                    /**
                     * @notice Removes an address from the access list
                     * @param _user The address to remove
                     */
                    function removeAccess(address _user)
                      external
                      onlyOwner()
                    {
                      if (accessList[_user]) {
                        accessList[_user] = false;
                        emit RemovedAccess(_user);
                      }
                    }
                    /**
                     * @notice makes the access check enforced
                     */
                    function enableAccessCheck()
                      external
                      onlyOwner()
                    {
                      if (!checkEnabled) {
                        checkEnabled = true;
                        emit CheckAccessEnabled();
                      }
                    }
                    /**
                     * @notice makes the access check unenforced
                     */
                    function disableAccessCheck()
                      external
                      onlyOwner()
                    {
                      if (checkEnabled) {
                        checkEnabled = false;
                        emit CheckAccessDisabled();
                      }
                    }
                    /**
                     * @dev reverts if the caller does not have access
                     */
                    modifier checkAccess() {
                      require(hasAccess(msg.sender, msg.data), "No access");
                      _;
                    }
                  }
                  // SPDX-License-Identifier: MIT
                  pragma solidity ^0.7.0;
                  import "./AccessControlledOffchainAggregator.sol";
                  import "./AccessControlTestHelper.sol";
                  contract TestOffchainAggregator is AccessControlledOffchainAggregator {
                    function testDecodeReport(
                      bytes memory report
                    ) public pure returns (bytes32, bytes32, int192[] memory)
                    {
                      return decodeReport(report);
                    }
                    constructor(
                      uint32 _maximumGasPrice,
                      uint32 _reasonableGasPrice,
                      uint32 _microLinkPerEth,
                      uint32 _linkGweiPerObservation,
                      uint32 _linkGweiPerTransmission,
                      address _link,
                      int192 _minAnswer, int192 _maxAnswer,
                      AccessControllerInterface _billingAccessController,
                      AccessControllerInterface _requesterAdminAccessController
                    )
                      AccessControlledOffchainAggregator(_maximumGasPrice, _reasonableGasPrice, _microLinkPerEth,
                        _linkGweiPerObservation, _linkGweiPerTransmission, _link,
                        _minAnswer, _maxAnswer, _billingAccessController, _requesterAdminAccessController, 0, "TEST"
                      )
                    {}
                    function testPayee(
                      address _transmitter
                    )
                      external
                      view
                      returns (address)
                    {
                      return s_payees[_transmitter];
                    }
                    function getConfigDigest() public view returns (bytes16) {
                      return s_hotVars.latestConfigDigest;
                    }
                    function testSaturatingAddUint16(uint16 _x, uint16 _y)
                      external pure returns (uint16)
                    {
                      return saturatingAddUint16(_x, _y);
                    }
                    function testImpliedGasPrice(uint256 txGasPrice, uint256 reasonableGasPrice,
                      uint256 maximumGasPrice
                    ) external pure returns (uint256) {
                      return impliedGasPrice(txGasPrice, reasonableGasPrice, maximumGasPrice);
                    }
                    function testTransmitterGasCostEthWei(uint256 initialGas, uint256 gasPrice,
                      uint256 callDataCost, uint256 gasLeft
                    ) external pure returns (uint128) {
                      return transmitterGasCostEthWei(
                        initialGas, gasPrice, callDataCost, gasLeft
                      );
                    }
                    function testSetOracleObservationCount(address _oracle, uint16 _amount) external {
                      s_oracleObservationsCounts[s_oracles[_oracle].index] = _amount + 1;
                    }
                    function testTotalLinkDue()
                      external view returns (uint256 linkDue)
                    {
                      return totalLINKDue();
                    }
                    function billingData() external view returns (
                      uint16[maxNumOracles] memory observationsCounts,
                      uint256[maxNumOracles] memory gasReimbursements,
                      uint32 maximumGasPrice,
                      uint32 reasonableGasPrice,
                      uint32 microLinkPerEth,
                      uint32 linkGweiPerObservation,
                      uint32 linkGweiPerTransmission
                    ) {
                      Billing memory b = s_billing;
                      return (s_oracleObservationsCounts, s_gasReimbursementsLinkWei,
                        b.maximumGasPrice, b.reasonableGasPrice, b.microLinkPerEth,
                        b.linkGweiPerObservation, b.linkGweiPerTransmission);
                    }
                    function testSetGasReimbursements(address _transmitterOrSigner, uint256 _amountLinkWei)
                      external
                    {
                      require(s_oracles[_transmitterOrSigner].role != Role.Unset, "address unknown");
                      s_gasReimbursementsLinkWei[s_oracles[_transmitterOrSigner].index] = _amountLinkWei + 1;
                    }
                    function testAccountingGasCost() public pure returns (uint256) {
                      return accountingGasCost;
                    }
                    function testBurnLINK(uint256 amount) public {
                        LINK.transfer(address(1), amount);
                    }
                  }
                  // SPDX-License-Identifier: MIT
                  pragma solidity ^0.7.1;
                  import "./AccessControlledOffchainAggregator.sol";
                  contract AccessControlTestHelper {
                    event Dummy(); // Used to silence warning that these methods are pure
                    function readGetRoundData(address _aggregator, uint80 _roundID)
                      external
                    {
                      AccessControlledOffchainAggregator(_aggregator).getRoundData(_roundID);
                      emit Dummy();
                    }
                    function readLatestRoundData(address _aggregator)
                      external
                    {
                      AccessControlledOffchainAggregator(_aggregator).latestRoundData();
                      emit Dummy();
                    }
                    function readLatestAnswer(address _aggregator)
                      external
                    {
                      AccessControlledOffchainAggregator(_aggregator).latestAnswer();
                      emit Dummy();
                    }
                    function readLatestTimestamp(address _aggregator)
                      external
                    {
                      AccessControlledOffchainAggregator(_aggregator).latestTimestamp();
                      emit Dummy();
                    }
                    function readLatestRound(address _aggregator)
                      external
                    {
                      AccessControlledOffchainAggregator(_aggregator).latestRound();
                      emit Dummy();
                    }
                    function readGetAnswer(address _aggregator, uint256 _roundID)
                      external
                    {
                      AccessControlledOffchainAggregator(_aggregator).getAnswer(_roundID);
                      emit Dummy();
                    }
                    function readGetTimestamp(address _aggregator, uint256 _roundID)
                      external
                    {
                      AccessControlledOffchainAggregator(_aggregator).getTimestamp(_roundID);
                      emit Dummy();
                    }
                    function testLatestTransmissionDetails(address _aggregator) external view {
                        OffchainAggregator(_aggregator).latestTransmissionDetails();
                    }
                  }
                  // SPDX-License-Identifier: MIT
                  pragma solidity ^0.7.0;
                  import "./OffchainAggregator.sol";
                  // ExposedOffchainAggregator exposes certain internal OffchainAggregator
                  // methods/structures so that golang code can access them, and we get
                  // reliable type checking on their usage
                  contract ExposedOffchainAggregator is OffchainAggregator {
                    constructor()
                      OffchainAggregator(
                        0, 0, 0, 0, 0, address(0), 0, 0, AccessControllerInterface(address(0)), AccessControllerInterface(address(0)), 0, ""
                      )
                      {}
                    function exposedConfigDigestFromConfigData(
                      address _contractAddress,
                      uint64 _configCount,
                      address[] calldata _signers,
                      address[] calldata _transmitters,
                      uint8 _threshold,
                      uint64 _encodedConfigVersion,
                      bytes calldata _encodedConfig
                    ) external pure returns (bytes16) {
                      return configDigestFromConfigData(_contractAddress, _configCount,
                        _signers, _transmitters, _threshold, _encodedConfigVersion,
                        _encodedConfig);
                    }
                  }
                  // SPDX-License-Identifier: MIT
                  pragma solidity ^0.7.0;
                  import "./AggregatorValidatorInterface.sol";
                  contract TestValidator is AggregatorValidatorInterface {
                    uint32 s_minGasUse;
                    uint256 s_latestRoundId;
                    event Validated(
                      uint256 previousRoundId,
                      int256 previousAnswer,
                      uint256 currentRoundId,
                      int256 currentAnswer,
                      uint256 initialGas
                    );
                    function validate(
                      uint256 previousRoundId,
                      int256 previousAnswer,
                      uint256 currentRoundId,
                      int256 currentAnswer
                    ) external override returns (bool) {
                      uint256 initialGas = gasleft();
                      emit Validated(
                        previousRoundId,
                        previousAnswer,
                        currentRoundId,
                        currentAnswer,
                        initialGas
                      );
                      s_latestRoundId = currentRoundId;
                      uint256 minGasUse = s_minGasUse;
                      while (initialGas - gasleft() < minGasUse) {}
                      return true;
                    }
                    function setMinGasUse(uint32 minGasUse) external {
                      s_minGasUse = minGasUse;
                    }
                    function latestRoundId() external view returns (uint256) {
                      return s_latestRoundId;
                    }
                  }