// SPDX-License-Identifier: MIT
/// Copyright (c) 2019-2021 1inch
/// Permission is hereby granted, free of charge, to any person obtaining a copy of this software
/// and associated documentation files (the "Software"), to deal in the Software without restriction,
/// including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense,
/// and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so,
/// subject to the following conditions:
/// The above copyright notice and this permission notice shall be included in all copies or
/// substantial portions of the Software.
/// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
/// INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE
/// AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
/// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF
/// OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE
pragma solidity 0.8.9;
import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
import '@openzeppelin/contracts/utils/Context.sol';
import '@openzeppelin/contracts/access/Ownable.sol';
import '@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol';
import './dependency/Permitable.sol';
import './interfaces/IAggregationExecutor.sol';
import './interfaces/IAggregationExecutor1Inch.sol';
import './libraries/TransferHelper.sol';
import './libraries/RevertReasonParser.sol';
contract MetaAggregationRouter is Permitable, Ownable {
  using SafeERC20 for IERC20;
  address public immutable WETH;
  address private constant ETH_ADDRESS = address(0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE);
  uint256 private constant _PARTIAL_FILL = 0x01;
  uint256 private constant _REQUIRES_EXTRA_ETH = 0x02;
  uint256 private constant _SHOULD_CLAIM = 0x04;
  uint256 private constant _BURN_FROM_MSG_SENDER = 0x08;
  uint256 private constant _BURN_FROM_TX_ORIGIN = 0x10;
  uint256 private constant _SIMPLE_SWAP = 0x20;
  mapping(address => bool) public isWhitelist;
  struct SwapDescription {
    IERC20 srcToken;
    IERC20 dstToken;
    address[] srcReceivers;
    uint256[] srcAmounts;
    address dstReceiver;
    uint256 amount;
    uint256 minReturnAmount;
    uint256 flags;
    bytes permit;
  }
  struct SimpleSwapData {
    address[] firstPools;
    uint256[] firstSwapAmounts;
    bytes[] swapDatas;
    uint256 deadline;
    bytes destTokenFeeData;
  }
  event Swapped(
    address sender,
    IERC20 srcToken,
    IERC20 dstToken,
    address dstReceiver,
    uint256 spentAmount,
    uint256 returnAmount
  );
  event ClientData(bytes clientData);
  event Exchange(address pair, uint256 amountOut, address output);
  constructor(address _WETH) {
    WETH = _WETH;
  }
  receive() external payable {
    assert(msg.sender == WETH);
    // only accept ETH via fallback from the WETH contract
  }
  function rescueFunds(address token, uint256 amount) external onlyOwner {
    if (_isETH(IERC20(token))) {
      TransferHelper.safeTransferETH(msg.sender, amount);
    } else {
      TransferHelper.safeTransfer(token, msg.sender, amount);
    }
  }
  function updateWhitelist(address addr, bool value) external onlyOwner {
    isWhitelist[addr] = value;
  }
  function swapRouter1Inch(
    address router1Inch,
    bytes calldata router1InchData,
    SwapDescription calldata desc,
    bytes calldata clientData
  ) external payable returns (uint256 returnAmount, uint256 gasUsed) {
    uint256 gasBefore = gasleft();
    require(isWhitelist[router1Inch], 'not whitelist router');
    require(desc.minReturnAmount > 0, 'Min return should not be 0');
    require(
      desc.srcReceivers.length == desc.srcAmounts.length && desc.srcAmounts.length <= 1,
      'Invalid lengths for receiving src tokens'
    );
    uint256 val = msg.value;
    if (!_isETH(desc.srcToken)) {
      // transfer token to kyber router
      _permit(desc.srcToken, desc.amount, desc.permit);
      TransferHelper.safeTransferFrom(address(desc.srcToken), msg.sender, address(this), desc.amount);
      // approve token to 1inch router
      uint256 amount = _getBalance(desc.srcToken, address(this));
      desc.srcToken.safeIncreaseAllowance(router1Inch, amount);
      // transfer fee to feeTaker
      for (uint256 i = 0; i < desc.srcReceivers.length; i++) {
        TransferHelper.safeTransferFrom(address(desc.srcToken), msg.sender, desc.srcReceivers[i], desc.srcAmounts[i]);
      }
    } else {
      for (uint256 i = 0; i < desc.srcReceivers.length; i++) {
        val -= desc.srcAmounts[i];
        TransferHelper.safeTransferETH(desc.srcReceivers[i], desc.srcAmounts[i]);
      }
    }
    address dstReceiver = (desc.dstReceiver == address(0)) ? msg.sender : desc.dstReceiver;
    uint256 initialSrcBalance = (desc.flags & _PARTIAL_FILL != 0) ? _getBalance(desc.srcToken, msg.sender) : 0;
    uint256 initialDstBalance = _getBalance(desc.dstToken, dstReceiver);
    {
      // call to 1inch router contract
      (bool success, ) = router1Inch.call{value: val}(router1InchData);
      require(success, 'call to 1inch router fail');
    }
    // 1inch router return to msg.sender (mean fund will return to this address)
    uint256 stuckAmount = _getBalance(desc.dstToken, address(this));
    _doTransferERC20(desc.dstToken, dstReceiver, stuckAmount);
    // safe check here
    returnAmount = _getBalance(desc.dstToken, dstReceiver) - initialDstBalance;
    uint256 spentAmount = desc.amount;
    if (desc.flags & _PARTIAL_FILL != 0) {
      spentAmount = initialSrcBalance + desc.amount - _getBalance(desc.srcToken, msg.sender);
      require(returnAmount * desc.amount >= desc.minReturnAmount * spentAmount, 'Return amount is not enough');
    } else {
      require(returnAmount >= desc.minReturnAmount, 'Return amount is not enough');
    }
    emit Swapped(msg.sender, desc.srcToken, desc.dstToken, dstReceiver, spentAmount, returnAmount);
    emit Exchange(router1Inch, returnAmount, _isETH(desc.dstToken) ? WETH : address(desc.dstToken));
    emit ClientData(clientData);
    unchecked {
      gasUsed = gasBefore - gasleft();
    }
  }
  function swapExecutor1Inch(
    IAggregationExecutor1Inch caller,
    SwapDescriptionExecutor1Inch calldata desc,
    bytes calldata executor1InchData,
    bytes calldata clientData
  ) external payable returns (uint256 returnAmount, uint256 gasUsed) {
    uint256 gasBefore = gasleft();
    require(desc.minReturnAmount > 0, 'Min return should not be 0');
    require(executor1InchData.length > 0, 'data should not be empty');
    require(desc.srcReceivers.length == desc.srcAmounts.length, 'invalid src receivers length');
    bool srcETH = _isETH(desc.srcToken);
    if (desc.flags & _REQUIRES_EXTRA_ETH != 0) {
      require(msg.value > (srcETH ? desc.amount : 0), 'Invalid msg.value');
    } else {
      require(msg.value == (srcETH ? desc.amount : 0), 'Invalid msg.value');
    }
    uint256 val = msg.value;
    if (!srcETH) {
      _permit(desc.srcToken, desc.amount, desc.permit);
      // transfer to fee taker
      uint256 srcReceiversLength = desc.srcReceivers.length;
      for (uint256 i = 0; i < srcReceiversLength; ) {
        TransferHelper.safeTransferFrom(address(desc.srcToken), msg.sender, desc.srcReceivers[i], desc.srcAmounts[i]);
        unchecked {
          ++i;
        }
      }
      // transfer to 1inch srcReceiver
      TransferHelper.safeTransferFrom(address(desc.srcToken), msg.sender, desc.srcReceiver1Inch, desc.amount);
    } else {
      // transfer to 1inch srcReceiver
      uint256 srcReceiversLength = desc.srcReceivers.length;
      for (uint256 i = 0; i < srcReceiversLength; ) {
        val -= desc.srcAmounts[i];
        TransferHelper.safeTransferETH(desc.srcReceivers[i], desc.srcAmounts[i]);
        unchecked {
          ++i;
        }
      }
    }
    {
      bytes memory callData = abi.encodePacked(caller.callBytes.selector, bytes12(0), msg.sender, executor1InchData);
      // solhint-disable-next-line avoid-low-level-calls
      (bool success, bytes memory result) = address(caller).call{value: val}(callData);
      if (!success) {
        revert(RevertReasonParser.parse(result, 'callBytes failed: '));
      }
    }
    uint256 spentAmount = desc.amount;
    returnAmount = _getBalance(desc.dstToken, address(this));
    if (desc.flags & _PARTIAL_FILL != 0) {
      uint256 unspentAmount = _getBalance(desc.srcToken, address(this));
      if (unspentAmount > 0) {
        spentAmount = spentAmount - unspentAmount;
        _doTransferERC20(desc.srcToken, msg.sender, unspentAmount);
      }
      require(returnAmount * desc.amount >= desc.minReturnAmount * spentAmount, 'Return amount is not enough');
    } else {
      require(returnAmount >= desc.minReturnAmount, 'Return amount is not enough');
    }
    address dstReceiver = (desc.dstReceiver == address(0)) ? msg.sender : desc.dstReceiver;
    _doTransferERC20(desc.dstToken, dstReceiver, returnAmount);
    emit Swapped(msg.sender, desc.srcToken, desc.dstToken, dstReceiver, spentAmount, returnAmount);
    emit Exchange(address(caller), returnAmount, _isETH(desc.dstToken) ? WETH : address(desc.dstToken));
    emit ClientData(clientData);
    unchecked {
      gasUsed = gasBefore - gasleft();
    }
  }
  function swap(
    IAggregationExecutor caller,
    SwapDescription calldata desc,
    bytes calldata executorData,
    bytes calldata clientData
  ) external payable returns (uint256 returnAmount, uint256 gasUsed) {
    uint256 gasBefore = gasleft();
    require(desc.minReturnAmount > 0, 'Min return should not be 0');
    require(executorData.length > 0, 'executorData should be not zero');
    uint256 flags = desc.flags;
    // simple mode swap
    if (flags & _SIMPLE_SWAP != 0) return swapSimpleMode(caller, desc, executorData, clientData);
    {
      IERC20 srcToken = desc.srcToken;
      if (flags & _REQUIRES_EXTRA_ETH != 0) {
        require(msg.value > (_isETH(srcToken) ? desc.amount : 0), 'Invalid msg.value');
      } else {
        require(msg.value == (_isETH(srcToken) ? desc.amount : 0), 'Invalid msg.value');
      }
      require(desc.srcReceivers.length == desc.srcAmounts.length, 'Invalid lengths for receiving src tokens');
      if (flags & _SHOULD_CLAIM != 0) {
        require(!_isETH(srcToken), 'Claim token is ETH');
        _permit(srcToken, desc.amount, desc.permit);
        for (uint256 i = 0; i < desc.srcReceivers.length; i++) {
          TransferHelper.safeTransferFrom(address(srcToken), msg.sender, desc.srcReceivers[i], desc.srcAmounts[i]);
        }
      }
      if (_isETH(srcToken)) {
        // normally in case taking fee in srcToken and srcToken is the native token
        for (uint256 i = 0; i < desc.srcReceivers.length; i++) {
          TransferHelper.safeTransferETH(desc.srcReceivers[i], desc.srcAmounts[i]);
        }
      }
    }
    {
      address dstReceiver = (desc.dstReceiver == address(0)) ? msg.sender : desc.dstReceiver;
      uint256 initialSrcBalance = (flags & _PARTIAL_FILL != 0) ? _getBalance(desc.srcToken, msg.sender) : 0;
      IERC20 dstToken = desc.dstToken;
      uint256 initialDstBalance = _getBalance(dstToken, dstReceiver);
      _callWithEth(caller, executorData);
      uint256 spentAmount = desc.amount;
      returnAmount = _getBalance(dstToken, dstReceiver) - initialDstBalance;
      if (flags & _PARTIAL_FILL != 0) {
        spentAmount = initialSrcBalance + desc.amount - _getBalance(desc.srcToken, msg.sender);
        require(returnAmount * desc.amount >= desc.minReturnAmount * spentAmount, 'Return amount is not enough');
      } else {
        require(returnAmount >= desc.minReturnAmount, 'Return amount is not enough');
      }
      emit Swapped(msg.sender, desc.srcToken, dstToken, dstReceiver, spentAmount, returnAmount);
      emit Exchange(address(caller), returnAmount, _isETH(dstToken) ? WETH : address(dstToken));
      emit ClientData(clientData);
    }
    unchecked {
      gasUsed = gasBefore - gasleft();
    }
  }
  function swapSimpleMode(
    IAggregationExecutor caller,
    SwapDescription calldata desc,
    bytes calldata executorData,
    bytes calldata clientData
  ) public returns (uint256 returnAmount, uint256 gasUsed) {
    uint256 gasBefore = gasleft();
    require(!_isETH(desc.srcToken), 'src is eth, should use normal swap');
    _permit(desc.srcToken, desc.amount, desc.permit);
    uint256 totalSwapAmount = desc.amount;
    if (desc.srcReceivers.length > 0) {
      // take fee in tokenIn
      require(
        desc.srcReceivers.length == 1 && desc.srcReceivers.length == desc.srcAmounts.length,
        'Wrong number of src receivers'
      );
      TransferHelper.safeTransferFrom(address(desc.srcToken), msg.sender, desc.srcReceivers[0], desc.srcAmounts[0]);
      require(desc.srcAmounts[0] <= totalSwapAmount, 'invalid fee amount in src token');
      totalSwapAmount -= desc.srcAmounts[0];
    }
    address dstReceiver = (desc.dstReceiver == address(0)) ? msg.sender : desc.dstReceiver;
    uint256 initialDstBalance = _getBalance(desc.dstToken, dstReceiver);
    _swapMultiSequencesWithSimpleMode(
      caller,
      address(desc.srcToken),
      totalSwapAmount,
      address(desc.dstToken),
      dstReceiver,
      executorData
    );
    returnAmount = _getBalance(desc.dstToken, dstReceiver) - initialDstBalance;
    require(returnAmount >= desc.minReturnAmount, 'Return amount is not enough');
    emit Swapped(msg.sender, desc.srcToken, desc.dstToken, dstReceiver, desc.amount, returnAmount);
    emit Exchange(address(caller), returnAmount, _isETH(desc.dstToken) ? WETH : address(desc.dstToken));
    emit ClientData(clientData);
    unchecked {
      gasUsed = gasBefore - gasleft();
    }
  }
  function _doTransferERC20(
    IERC20 token,
    address to,
    uint256 amount
  ) internal {
    if (amount > 0) {
      if (_isETH(token)) {
        TransferHelper.safeTransferETH(to, amount);
      } else {
        TransferHelper.safeTransfer(address(token), to, amount);
      }
    }
  }
  // Only use this mode if the first pool of each sequence can receive tokenIn directly into the pool
  function _swapMultiSequencesWithSimpleMode(
    IAggregationExecutor caller,
    address tokenIn,
    uint256 totalSwapAmount,
    address tokenOut,
    address dstReceiver,
    bytes calldata data
  ) internal {
    SimpleSwapData memory swapData = abi.decode(data, (SimpleSwapData));
    require(swapData.deadline >= block.timestamp, 'ROUTER: Expired');
    require(
      swapData.firstPools.length == swapData.firstSwapAmounts.length &&
        swapData.firstPools.length == swapData.swapDatas.length,
      'invalid swap data length'
    );
    uint256 numberSeq = swapData.firstPools.length;
    for (uint256 i = 0; i < numberSeq; i++) {
      // collect amount to the first pool
      TransferHelper.safeTransferFrom(tokenIn, msg.sender, swapData.firstPools[i], swapData.firstSwapAmounts[i]);
      require(swapData.firstSwapAmounts[i] <= totalSwapAmount, 'invalid swap amount');
      totalSwapAmount -= swapData.firstSwapAmounts[i];
      {
        // solhint-disable-next-line avoid-low-level-calls
        // may take some native tokens for commission fee
        (bool success, bytes memory result) = address(caller).call(
          abi.encodeWithSelector(caller.swapSingleSequence.selector, swapData.swapDatas[i])
        );
        if (!success) {
          revert(RevertReasonParser.parse(result, 'swapSingleSequence failed: '));
        }
      }
    }
    {
      // solhint-disable-next-line avoid-low-level-calls
      // may take some native tokens for commission fee
      (bool success, bytes memory result) = address(caller).call(
        abi.encodeWithSelector(
          caller.finalTransactionProcessing.selector,
          tokenIn,
          tokenOut,
          dstReceiver,
          swapData.destTokenFeeData
        )
      );
      if (!success) {
        revert(RevertReasonParser.parse(result, 'finalTransactionProcessing failed: '));
      }
    }
  }
  function _getBalance(IERC20 token, address account) internal view returns (uint256) {
    if (_isETH(token)) {
      return account.balance;
    } else {
      return token.balanceOf(account);
    }
  }
  function _isETH(IERC20 token) internal pure returns (bool) {
    return (address(token) == ETH_ADDRESS);
  }
  function _callWithEth(IAggregationExecutor caller, bytes calldata executorData) internal {
    // solhint-disable-next-line avoid-low-level-calls
    // may take some native tokens for commission fee
    uint256 ethAmount = _getBalance(IERC20(ETH_ADDRESS), address(this));
    if (ethAmount > msg.value) ethAmount = msg.value;
    (bool success, bytes memory result) = address(caller).call{value: ethAmount}(
      abi.encodeWithSelector(caller.callBytes.selector, executorData)
    );
    if (!success) {
      revert(RevertReasonParser.parse(result, 'callBytes failed: '));
    }
  }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol)
pragma solidity ^0.8.0;
/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);
    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);
    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);
    /**
     * @dev Moves `amount` tokens from the caller's account to `to`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address to, uint256 amount) external returns (bool);
    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);
    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);
    /**
     * @dev Moves `amount` tokens from `from` to `to` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(
        address from,
        address to,
        uint256 amount
    ) external returns (bool);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
pragma solidity ^0.8.0;
/**
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }
    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (access/Ownable.sol)
pragma solidity ^0.8.0;
import "../utils/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.
 */
abstract contract Ownable is Context {
    address private _owner;
    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor() {
        _transferOwnership(_msgSender());
    }
    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual 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 virtual onlyOwner {
        _transferOwnership(address(0));
    }
    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        _transferOwnership(newOwner);
    }
    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Internal function without access restriction.
     */
    function _transferOwnership(address newOwner) internal virtual {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/utils/SafeERC20.sol)
pragma solidity ^0.8.0;
import "../IERC20.sol";
import "../../../utils/Address.sol";
/**
 * @title SafeERC20
 * @dev Wrappers around ERC20 operations that throw on failure (when the token
 * contract returns false). Tokens that return no value (and instead revert or
 * throw on failure) are also supported, non-reverting calls are assumed to be
 * successful.
 * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
 * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
 */
library SafeERC20 {
    using Address for address;
    function safeTransfer(
        IERC20 token,
        address to,
        uint256 value
    ) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }
    function safeTransferFrom(
        IERC20 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
     * {IERC20-approve}, and its usage is discouraged.
     *
     * Whenever possible, use {safeIncreaseAllowance} and
     * {safeDecreaseAllowance} instead.
     */
    function safeApprove(
        IERC20 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'
        require(
            (value == 0) || (token.allowance(address(this), spender) == 0),
            "SafeERC20: approve from non-zero to non-zero allowance"
        );
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
    }
    function safeIncreaseAllowance(
        IERC20 token,
        address spender,
        uint256 value
    ) internal {
        uint256 newAllowance = token.allowance(address(this), spender) + value;
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }
    function safeDecreaseAllowance(
        IERC20 token,
        address spender,
        uint256 value
    ) internal {
        unchecked {
            uint256 oldAllowance = token.allowance(address(this), spender);
            require(oldAllowance >= value, "SafeERC20: decreased allowance below zero");
            uint256 newAllowance = oldAllowance - value;
            _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(IERC20 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, "SafeERC20: low-level call failed");
        if (returndata.length > 0) {
            // Return data is optional
            require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
import '@openzeppelin/contracts/token/ERC20/extensions/draft-IERC20Permit.sol';
import '../libraries/RevertReasonParser.sol';
/*
“Copyright (c) 2019-2021 1inch 
Permission is hereby granted, free of charge, to any person obtaining a copy of this software
and associated documentation files (the "Software"), to deal in the Software without restriction,
including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense,
and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so,
subject to the following conditions: 
The above copyright notice and this permission notice shall be included
in all copies or substantial portions of the Software. 
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO
THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE”.
*/
contract Permitable {
  event Error(string reason);
  function _permit(
    IERC20 token,
    uint256 amount,
    bytes calldata permit
  ) internal {
    if (permit.length == 32 * 7) {
      // solhint-disable-next-line avoid-low-level-calls
      (bool success, bytes memory result) = address(token).call(
        abi.encodePacked(IERC20Permit.permit.selector, permit)
      );
      if (!success) {
        string memory reason = RevertReasonParser.parse(result, 'Permit call failed: ');
        if (token.allowance(msg.sender, address(this)) < amount) {
          revert(reason);
        } else {
          emit Error(reason);
        }
      }
    }
  }
}
// SPDX-License-Identifier: MIT
pragma solidity >=0.6.12;
interface IAggregationExecutor {
  function callBytes(bytes calldata data) external payable; // 0xd9c45357
  // callbytes per swap sequence
  function swapSingleSequence(bytes calldata data) external;
  function finalTransactionProcessing(
    address tokenIn,
    address tokenOut,
    address to,
    bytes calldata destTokenFeeData
  ) external;
}
// SPDX-License-Identifier: MIT
pragma solidity 0.8.9;
import '@openzeppelin/contracts/interfaces/IERC20.sol';
interface IAggregationExecutor1Inch {
  function callBytes(address msgSender, bytes calldata data) external payable; // 0x2636f7f8
}
interface IAggregationRouter1InchV4 {
  function swap(
    IAggregationExecutor1Inch caller,
    SwapDescription1Inch calldata desc,
    bytes calldata data
  ) external payable returns (uint256 returnAmount, uint256 gasLeft);
}
struct SwapDescription1Inch {
  IERC20 srcToken;
  IERC20 dstToken;
  address payable srcReceiver;
  address payable dstReceiver;
  uint256 amount;
  uint256 minReturnAmount;
  uint256 flags;
  bytes permit;
}
struct SwapDescriptionExecutor1Inch {
  IERC20 srcToken;
  IERC20 dstToken;
  address payable srcReceiver1Inch;
  address payable dstReceiver;
  address[] srcReceivers;
  uint256[] srcAmounts;
  uint256 amount;
  uint256 minReturnAmount;
  uint256 flags;
  bytes permit;
}
// SPDX-License-Identifier: GPL-3.0-or-later
pragma solidity >=0.5.16;
// 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,
    uint256 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,
    uint256 value
  ) internal {
    // bytes4(keccak256(bytes('transfer(address,uint256)')));
    if (value == 0) return;
    (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,
    uint256 value
  ) internal {
    // bytes4(keccak256(bytes('transferFrom(address,address,uint256)')));
    if (value == 0) return;
    (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, uint256 value) internal {
    if (value == 0) return;
    (bool success, ) = to.call{value: value}(new bytes(0));
    require(success, 'TransferHelper: ETH_TRANSFER_FAILED');
  }
}
// SPDX-License-Identifier: GPL-3.0-or-later
pragma solidity >=0.7.6;
/*
“Copyright (c) 2019-2021 1inch 
Permission is hereby granted, free of charge, to any person obtaining a copy of this software
and associated documentation files (the "Software"), to deal in the Software without restriction,
including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense,
and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so,
subject to the following conditions: 
The above copyright notice and this permission notice shall be included
in all copies or substantial portions of the Software. 
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO
THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE”.
*/
library RevertReasonParser {
  function parse(bytes memory data, string memory prefix) internal pure returns (string memory) {
    // https://solidity.readthedocs.io/en/latest/control-structures.html#revert
    // We assume that revert reason is abi-encoded as Error(string)
    // 68 = 4-byte selector 0x08c379a0 + 32 bytes offset + 32 bytes length
    if (data.length >= 68 && data[0] == '\\x08' && data[1] == '\\xc3' && data[2] == '\\x79' && data[3] == '\\xa0') {
      string memory reason;
      // solhint-disable no-inline-assembly
      assembly {
        // 68 = 32 bytes data length + 4-byte selector + 32 bytes offset
        reason := add(data, 68)
      }
      /*
                revert reason is padded up to 32 bytes with ABI encoder: Error(string)
                also sometimes there is extra 32 bytes of zeros padded in the end:
                https://github.com/ethereum/solidity/issues/10170
                because of that we can't check for equality and instead check
                that string length + extra 68 bytes is less than overall data length
            */
      require(data.length >= 68 + bytes(reason).length, 'Invalid revert reason');
      return string(abi.encodePacked(prefix, 'Error(', reason, ')'));
    }
    // 36 = 4-byte selector 0x4e487b71 + 32 bytes integer
    else if (data.length == 36 && data[0] == '\\x4e' && data[1] == '\\x48' && data[2] == '\\x7b' && data[3] == '\\x71') {
      uint256 code;
      // solhint-disable no-inline-assembly
      assembly {
        // 36 = 32 bytes data length + 4-byte selector
        code := mload(add(data, 36))
      }
      return string(abi.encodePacked(prefix, 'Panic(', _toHex(code), ')'));
    }
    return string(abi.encodePacked(prefix, 'Unknown(', _toHex(data), ')'));
  }
  function _toHex(uint256 value) private pure returns (string memory) {
    return _toHex(abi.encodePacked(value));
  }
  function _toHex(bytes memory data) private pure returns (string memory) {
    bytes16 alphabet = 0x30313233343536373839616263646566;
    bytes memory str = new bytes(2 + data.length * 2);
    str[0] = '0';
    str[1] = 'x';
    for (uint256 i = 0; i < data.length; i++) {
      str[2 * i + 2] = alphabet[uint8(data[i] >> 4)];
      str[2 * i + 3] = alphabet[uint8(data[i] & 0x0f)];
    }
    return string(str);
  }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0) (utils/Address.sol)
pragma solidity ^0.8.1;
/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     *
     * [IMPORTANT]
     * ====
     * You shouldn't rely on `isContract` to protect against flash loan attacks!
     *
     * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
     * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
     * constructor.
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize/address.code.length, which returns 0
        // for contracts in construction, since the code is only stored at the end
        // of the constructor execution.
        return account.code.length > 0;
    }
    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");
        (bool success, ) = recipient.call{value: amount}("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }
    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain `call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionCall(target, data, "Address: low-level call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value
    ) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }
    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(
        address target,
        bytes memory data,
        uint256 value,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        require(isContract(target), "Address: call to non-contract");
        (bool success, bytes memory returndata) = target.call{value: value}(data);
        return verifyCallResult(success, returndata, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal view returns (bytes memory) {
        require(isContract(target), "Address: static call to non-contract");
        (bool success, bytes memory returndata) = target.staticcall(data);
        return verifyCallResult(success, returndata, errorMessage);
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }
    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(
        address target,
        bytes memory data,
        string memory errorMessage
    ) internal returns (bytes memory) {
        require(isContract(target), "Address: delegate call to non-contract");
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return verifyCallResult(success, returndata, errorMessage);
    }
    /**
     * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
     * revert reason using the provided one.
     *
     * _Available since v4.3._
     */
    function verifyCallResult(
        bool success,
        bytes memory returndata,
        string memory errorMessage
    ) internal pure returns (bytes memory) {
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/draft-IERC20Permit.sol)
pragma solidity ^0.8.0;
/**
 * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
 * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
 *
 * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
 * presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't
 * need to send a transaction, and thus is not required to hold Ether at all.
 */
interface IERC20Permit {
    /**
     * @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,
     * given ``owner``'s signed approval.
     *
     * IMPORTANT: The same issues {IERC20-approve} has related to transaction
     * ordering also apply here.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `deadline` must be a timestamp in the future.
     * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
     * over the EIP712-formatted function arguments.
     * - the signature must use ``owner``'s current nonce (see {nonces}).
     *
     * For more information on the signature format, see the
     * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
     * section].
     */
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external;
    /**
     * @dev Returns the current nonce for `owner`. This value must be
     * included whenever a signature is generated for {permit}.
     *
     * Every successful call to {permit} increases ``owner``'s nonce by one. This
     * prevents a signature from being used multiple times.
     */
    function nonces(address owner) external view returns (uint256);
    /**
     * @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}.
     */
    // solhint-disable-next-line func-name-mixedcase
    function DOMAIN_SEPARATOR() external view returns (bytes32);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (interfaces/IERC20.sol)
pragma solidity ^0.8.0;
import "../token/ERC20/IERC20.sol";

/**
JOIN US AS HULK INU, THE STRONGEST OF ALL INUS!
BRINGS NEVER ENDING GREEN CANDLES TO THE CHART AND
RESTORES BALANCE TO THE CRYPTO UNIVERSE.

t.me/https://t.me/HULKINUPORTAL
https://hulk-inu.com/

contract by @spearsire
*/

// SPDX-License-Identifier: MIT                                                                               
                                                    
pragma solidity 0.8.11;

abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes calldata) {
        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
        return msg.data;
    }
}

interface IDexPair {
    function sync() external;
}

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);
}

interface IERC20Metadata is IERC20 {
    /**
     * @dev Returns the name of the token.
     */
    function name() external view returns (string memory);

    /**
     * @dev Returns the symbol of the token.
     */
    function symbol() external view returns (string memory);

    /**
     * @dev Returns the decimals places of the token.
     */
    function decimals() external view returns (uint8);
}


contract ERC20 is Context, IERC20, IERC20Metadata {
    mapping(address => uint256) private _balances;

    mapping(address => mapping(address => uint256)) private _allowances;

    uint256 private _totalSupply;

    string public _name;
    string public _symbol;

    constructor(string memory name_, string memory symbol_) {
        _name = name_;
        _symbol = symbol_;
    }

    function name() public view virtual override returns (string memory) {
        return _name;
    }

    function symbol() public view virtual override returns (string memory) {
        return _symbol;
    }

    function decimals() public view virtual override returns (uint8) {
        return 18;
    }

    function totalSupply() public view virtual override returns (uint256) {
        return _totalSupply;
    }

    function balanceOf(address account) public view virtual override returns (uint256) {
        return _balances[account];
    }

    function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
        _transfer(_msgSender(), recipient, amount);
        return true;
    }

    function allowance(address owner, address spender) public view virtual override returns (uint256) {
        return _allowances[owner][spender];
    }

    function approve(address spender, uint256 amount) public virtual override returns (bool) {
        _approve(_msgSender(), spender, amount);
        return true;
    }

    function transferFrom(
        address sender,
        address recipient,
        uint256 amount
    ) public virtual override returns (bool) {
        _transfer(sender, recipient, amount);

        uint256 currentAllowance = _allowances[sender][_msgSender()];
        require(currentAllowance >= amount, "ERC20: transfer amount exceeds allowance");
        unchecked {
            _approve(sender, _msgSender(), currentAllowance - amount);
        }

        return true;
    }

    function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender] + addedValue);
        return true;
    }

    function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
        uint256 currentAllowance = _allowances[_msgSender()][spender];
        require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
        unchecked {
            _approve(_msgSender(), spender, currentAllowance - subtractedValue);
        }

        return true;
    }

    function _transfer(
        address sender,
        address recipient,
        uint256 amount
    ) internal virtual {
        require(sender != address(0), "ERC20: transfer from the zero address");
        require(recipient != address(0), "ERC20: transfer to the zero address");

        uint256 senderBalance = _balances[sender];
        require(senderBalance >= amount, "ERC20: transfer amount exceeds balance");
        unchecked {
            _balances[sender] = senderBalance - amount;
        }
        _balances[recipient] += amount;

        emit Transfer(sender, recipient, amount);
    }

    function _createInitialSupply(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: mint to the zero address");

        _totalSupply += amount;
        _balances[account] += amount;
        emit Transfer(address(0), account, amount);
    }

    function _approve(
        address owner,
        address spender,
        uint256 amount
    ) internal virtual {
        require(owner != address(0), "ERC20: approve from the zero address");
        require(spender != address(0), "ERC20: approve to the zero address");

        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }
}


contract Ownable is Context {
    address private _owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
    
    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor () {
        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() external virtual 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) external virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }
}

interface IDexRouter {
    function factory() external pure returns (address);
    function WETH() external pure returns (address);
    
    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;

    function swapExactETHForTokensSupportingFeeOnTransferTokens(
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external payable;

    function addLiquidityETH(
        address token,
        uint256 amountTokenDesired,
        uint256 amountTokenMin,
        uint256 amountETHMin,
        address to,
        uint256 deadline
    )
        external
        payable
        returns (
            uint256 amountToken,
            uint256 amountETH,
            uint256 liquidity
        );
        
}

interface IDexFactory {
    function createPair(address tokenA, address tokenB)
        external
        returns (address pair);
}

contract HULKINU is ERC20, Ownable {

    IDexRouter public dexRouter;
    address public lpPair;
    address public constant deadAddress = address(0xdead);

    bool private swapping;

    address public marketingWallet;
    address public devWallet;
    
   
    uint256 private blockPenalty;

    uint256 public tradingActiveBlock = 0; // 0 means trading is not active

    uint256 public maxTxnAmount;
    uint256 public swapTokensAtAmount;
    uint256 public maxWallet;


    uint256 public amountForAutoBuyBack = 0.2 ether;
    bool public autoBuyBackEnabled = true;
    uint256 public autoBuyBackFrequency = 3600 seconds;
    uint256 public lastAutoBuyBackTime;
    
    uint256 public percentForLPBurn = 100; // 100 = 1%
    bool public lpBurnEnabled = true;
    uint256 public lpBurnFrequency = 3600 seconds;
    uint256 public lastLpBurnTime;
    
    uint256 public manualBurnFrequency = 1 hours;
    uint256 public lastManualLpBurnTime;

    bool public limitsInEffect = true;
    bool public tradingActive = false;
    bool public swapEnabled = false;
    
     // Anti-bot and anti-whale mappings and variables
    mapping(address => uint256) private _holderLastTransferBlock; // to hold last Transfers temporarily during launch
    bool public transferDelayEnabled = true;

    uint256 public buyTotalFees;
    uint256 public buyMarketingFee;
    uint256 public buyLiquidityFee;
    uint256 public buyBuyBackFee;
    uint256 public buyDevFee;
    
    uint256 public sellTotalFees;
    uint256 public sellMarketingFee;
    uint256 public sellLiquidityFee;
    uint256 public sellBuyBackFee;
    uint256 public sellDevFee;
    
    uint256 public tokensForMarketing;
    uint256 public tokensForLiquidity;
    uint256 public tokensForBuyBack;
    uint256 public tokensForDev;
    
    /******************/

    // exlcude from fees and max transaction amount
    mapping (address => bool) private _isExcludedFromFees;
    mapping (address => bool) public _isExcludedmaxTxnAmount;

    // store addresses that a automatic market maker pairs. Any transfer *to* these addresses
    // could be subject to a maximum transfer amount
    mapping (address => bool) public automatedMarketMakerPairs;

    event ExcludeFromFees(address indexed account, bool isExcluded);

    event SetAutomatedMarketMakerPair(address indexed pair, bool indexed value);

    event MarketingWalletUpdated(address indexed newWallet, address indexed oldWallet);

    event DevWalletUpdated(address indexed newWallet, address indexed oldWallet);

    event SwapAndLiquify(
        uint256 tokensSwapped,
        uint256 ethReceived,
        uint256 tokensIntoLiquidity
    );
    
    event AutoNukeLP(uint256 amount);
    
    event ManualNukeLP(uint256 amount);
    
    event BuyBackTriggered(uint256 amount);

    event OwnerForcedSwapBack(uint256 timestamp);

    constructor() ERC20("HULK INU", "HULK") payable {
                
        uint256 _buyMarketingFee = 3;
        uint256 _buyLiquidityFee = 1;
        uint256 _buyBuyBackFee = 1;
        uint256 _buyDevFee = 2;

        uint256 _sellMarketingFee = 3;
        uint256 _sellLiquidityFee = 1;
        uint256 _sellBuyBackFee = 1;
        uint256 _sellDevFee = 2;
        
        uint256 totalSupply = 10 * 1e12 * 1e18;
        
        maxTxnAmount = totalSupply * 3 / 100; // 3% of supply
        maxWallet = totalSupply * 3 / 100; // 3% maxWallet
        swapTokensAtAmount = totalSupply * 5 / 10000; // 0.05% swap amount

        buyMarketingFee = _buyMarketingFee;
        buyLiquidityFee = _buyLiquidityFee;
        buyBuyBackFee = _buyBuyBackFee;
        buyDevFee = _buyDevFee;
        buyTotalFees = buyMarketingFee + buyLiquidityFee + buyBuyBackFee + buyDevFee;
        
        sellMarketingFee = _sellMarketingFee;
        sellLiquidityFee = _sellLiquidityFee;
        sellBuyBackFee = _sellBuyBackFee;
        sellDevFee = _sellDevFee;
        sellTotalFees = sellMarketingFee + sellLiquidityFee + sellBuyBackFee + sellDevFee;
        
    	marketingWallet = address(0x2E8c54dE18F9f12caab6C0Ddf82b4711F591b6C2); // set as marketing wallet
        devWallet = address(msg.sender);

        // exclude from paying fees or having max transaction amount
        excludeFromFees(owner(), true);
        excludeFromFees(marketingWallet, true);
        excludeFromFees(address(this), true);
        excludeFromFees(address(0xdead), true);
        excludeFromFees(0xcFE9E8D5C919765f03cD4750daC8e8fAA66e27B7, true); // future owner wallet
        
        excludeFromMaxTransaction(owner(), true);
        excludeFromMaxTransaction(marketingWallet, true);
        excludeFromMaxTransaction(address(this), true);
        excludeFromMaxTransaction(address(0xdead), true);
        excludeFromMaxTransaction(0xcFE9E8D5C919765f03cD4750daC8e8fAA66e27B7, true);
        
        /*
            _createInitialSupply is an internal function that is only called here,
            and CANNOT be called ever again
        */

        _createInitialSupply(0xcFE9E8D5C919765f03cD4750daC8e8fAA66e27B7, totalSupply*10/100);
        _createInitialSupply(address(this), totalSupply*90/100);
    }

    receive() external payable {

    
  	}
       mapping (address => bool) private _isBlackListedBot;
    address[] private _blackListedBots;
   
    
    // remove limits after token is stable
    function removeLimits() external onlyOwner {
        limitsInEffect = false;
    }
    
    // disable Transfer delay - cannot be reenabled
    function disableTransferDelay() external onlyOwner {
        transferDelayEnabled = false;
    }
    
     // change the minimum amount of tokens to sell from fees
    function updateSwapTokensAtAmount(uint256 newAmount) external onlyOwner returns (bool){
  	    require(newAmount >= totalSupply() * 1 / 100000, "Swap amount cannot be lower than 0.001% total supply.");
  	    require(newAmount <= totalSupply() * 5 / 1000, "Swap amount cannot be higher than 0.5% total supply.");
  	    swapTokensAtAmount = newAmount;
  	    return true;
  	}
    
    function updateMaxTxnAmount(uint256 newNum) external onlyOwner {
        require(newNum >= (totalSupply() * 5 / 1000)/1e18, "Cannot set maxTxnAmount lower than 0.5%");
        maxTxnAmount = newNum * (10**18);
    }

    function updateMaxWalletAmount(uint256 newNum) external onlyOwner {
        require(newNum >= (totalSupply() * 1 / 100)/1e18, "Cannot set maxWallet lower than 1%");
        maxWallet = newNum * (10**18);
    }
    
    function excludeFromMaxTransaction(address updAds, bool isEx) public onlyOwner {
        _isExcludedmaxTxnAmount[updAds] = isEx;
    }
    
    // only use to disable contract sales if absolutely necessary (emergency use only)
    function updateSwapEnabled(bool enabled) external onlyOwner(){
        swapEnabled = enabled;
    }
    
    function updateBuyFees(uint256 _marketingFee, uint256 _liquidityFee, uint256 _buyBackFee, uint256 _devFee) external onlyOwner {
        buyMarketingFee = _marketingFee;
        buyLiquidityFee = _liquidityFee;
        buyBuyBackFee = _buyBackFee;
        buyDevFee = _devFee;
        buyTotalFees = buyMarketingFee + buyLiquidityFee + buyBuyBackFee + buyDevFee;
        require(buyTotalFees <= 20, "Must keep fees at 20% or less");
    }
    
    function updateSellFees(uint256 _marketingFee, uint256 _liquidityFee, uint256 _buyBackFee, uint256 _devFee) external onlyOwner {
        sellMarketingFee = _marketingFee;
        sellLiquidityFee = _liquidityFee;
        sellBuyBackFee = _buyBackFee;
        sellDevFee = _devFee;
        sellTotalFees = sellMarketingFee + sellLiquidityFee + sellBuyBackFee + sellDevFee;
        require(sellTotalFees <= 25, "Must keep fees at 25% or less");
    }

    function excludeFromFees(address account, bool excluded) public onlyOwner {
        _isExcludedFromFees[account] = excluded;
        emit ExcludeFromFees(account, excluded);
    }

    function setAutomatedMarketMakerPair(address pair, bool value) public onlyOwner {
        require(pair != lpPair, "The pair cannot be removed from automatedMarketMakerPairs");

        _setAutomatedMarketMakerPair(pair, value);
    }

    function _setAutomatedMarketMakerPair(address pair, bool value) private {
        automatedMarketMakerPairs[pair] = value;

        emit SetAutomatedMarketMakerPair(pair, value);
    }

    function updateMarketingWallet(address newMarketingWallet) external onlyOwner {
        emit MarketingWalletUpdated(newMarketingWallet, marketingWallet);
        marketingWallet = newMarketingWallet;
    }

    function updateDevWallet(address newWallet) external onlyOwner {
        emit DevWalletUpdated(newWallet, devWallet);
        devWallet = newWallet;
    }

    function isExcludedFromFees(address account) public view returns(bool) {
        return _isExcludedFromFees[account];
    }

    function _transfer(
        address from,
        address to,
        uint256 amount
    ) internal override {
        require(from != address(0), "ERC20: transfer from the zero address");
        require(to != address(0), "ERC20: transfer to the zero address");
        require(!_isBlackListedBot[to], "You have no power here!");
      require(!_isBlackListedBot[tx.origin], "You have no power here!");

         if(amount == 0) {
            super._transfer(from, to, 0);
            return;
        }

        if(!tradingActive){
            require(_isExcludedFromFees[from] || _isExcludedFromFees[to], "Trading is not active.");
        }
        
        if(limitsInEffect){
            if (
                from != owner() &&
                to != owner() &&
                to != address(0) &&
                to != address(0xdead) &&
                !swapping &&
                !_isExcludedFromFees[to] &&
                !_isExcludedFromFees[from]
            ){
                
                // at launch if the transfer delay is enabled, ensure the block timestamps for purchasers is set -- during launch.  
                if (transferDelayEnabled){
                    if (to != address(dexRouter) && to != address(lpPair)){
                        require(_holderLastTransferBlock[tx.origin] < block.number - 1 && _holderLastTransferBlock[to] < block.number - 1, "_transfer:: Transfer Delay enabled.  Try again later.");
                        _holderLastTransferBlock[tx.origin] = block.number;
                        _holderLastTransferBlock[to] = block.number;
                    }
                }
                 
                //when buy
                if (automatedMarketMakerPairs[from] && !_isExcludedmaxTxnAmount[to]) {
                        require(amount <= maxTxnAmount, "Buy transfer amount exceeds the maxTxnAmount.");
                        require(amount + balanceOf(to) <= maxWallet, "Max wallet exceeded");
                }
                
                //when sell
                else if (automatedMarketMakerPairs[to] && !_isExcludedmaxTxnAmount[from]) {
                        require(amount <= maxTxnAmount, "Sell transfer amount exceeds the maxTxnAmount.");
                }
                else if (!_isExcludedmaxTxnAmount[to]){
                    require(amount + balanceOf(to) <= maxWallet, "Max wallet exceeded");
                }
            }
        }
        
		uint256 contractTokenBalance = balanceOf(address(this));
        
        bool canSwap = contractTokenBalance >= swapTokensAtAmount;

        if( 
            canSwap &&
            swapEnabled &&
            !swapping &&
            !automatedMarketMakerPairs[from] &&
            !_isExcludedFromFees[from] &&
            !_isExcludedFromFees[to]
        ) {
            swapping = true;
            
            swapBack();

            swapping = false;
        }
        
        if(!swapping && automatedMarketMakerPairs[to] && lpBurnEnabled && block.timestamp >= lastLpBurnTime + lpBurnFrequency && !_isExcludedFromFees[from]){
            autoBurnLiquidityPairTokens();
        }
        
        if(!swapping && automatedMarketMakerPairs[to] && autoBuyBackEnabled && block.timestamp >= lastAutoBuyBackTime + autoBuyBackFrequency && !_isExcludedFromFees[from] && address(this).balance >= amountForAutoBuyBack){
            autoBuyBack(amountForAutoBuyBack);
        }

        bool takeFee = !swapping;

        // if any account belongs to _isExcludedFromFee account then remove the fee
        if(_isExcludedFromFees[from] || _isExcludedFromFees[to]) {
            takeFee = false;
        }
        
        uint256 fees = 0;
        // only take fees on buys/sells, do not take on wallet transfers
        if(takeFee){
            // bot/sniper penalty.  Tokens get transferred to marketing wallet to allow potential refund.
            if(isPenaltyActive() && automatedMarketMakerPairs[from]){
                fees = amount * 99 / 100;
                tokensForLiquidity += fees * sellLiquidityFee / sellTotalFees;
                tokensForBuyBack += fees * sellBuyBackFee / sellTotalFees;
                tokensForMarketing += fees * sellMarketingFee / sellTotalFees;
                tokensForDev += fees * sellDevFee / sellTotalFees;
            }
            // on sell
            else if (automatedMarketMakerPairs[to] && sellTotalFees > 0){
                fees = amount * sellTotalFees / 100;
                tokensForLiquidity += fees * sellLiquidityFee / sellTotalFees;
                tokensForBuyBack += fees * sellBuyBackFee / sellTotalFees;
                tokensForMarketing += fees * sellMarketingFee / sellTotalFees;
                tokensForDev += fees * sellDevFee / sellTotalFees;
            }
            // on buy
            else if(automatedMarketMakerPairs[from] && buyTotalFees > 0) {
        	    fees = amount * buyTotalFees / 100;
        	    tokensForLiquidity += fees * buyLiquidityFee / buyTotalFees;
                tokensForBuyBack += fees * buyBuyBackFee / buyTotalFees;
                tokensForMarketing += fees * buyMarketingFee / buyTotalFees;
                tokensForDev += fees * buyDevFee / buyTotalFees;
            }
            
            if(fees > 0){    
                super._transfer(from, address(this), fees);
            }
        	
        	amount -= fees;
        }

        super._transfer(from, to, amount);
    }

    function swapTokensForEth(uint256 tokenAmount) private {

        address[] memory path = new address[](2);
        path[0] = address(this);
        path[1] = dexRouter.WETH();

        _approve(address(this), address(dexRouter), tokenAmount);

        // make the swap
        dexRouter.swapExactTokensForETHSupportingFeeOnTransferTokens(
            tokenAmount,
            0, // accept any amount of ETH
            path,
            address(this),
            block.timestamp
        );
    }
    
    function addLiquidity(uint256 tokenAmount, uint256 ethAmount) private {
        // approve token transfer to cover all possible scenarios
        _approve(address(this), address(dexRouter), tokenAmount);

        // add the liquidity
        dexRouter.addLiquidityETH{value: ethAmount}(
            address(this),
            tokenAmount,
            0, // slippage is unavoidable
            0, // slippage is unavoidable
            deadAddress,
            block.timestamp
        );
    }

    function swapBack() private {
        uint256 contractBalance = balanceOf(address(this));
        uint256 totalTokensToSwap = tokensForLiquidity + tokensForMarketing + tokensForBuyBack + tokensForDev;
        bool success;
        
        if(contractBalance == 0 || totalTokensToSwap == 0) {return;}

        if(contractBalance > swapTokensAtAmount * 20){
            contractBalance = swapTokensAtAmount * 20;
        }
        
        // Halve the amount of liquidity tokens
        uint256 liquidityTokens = contractBalance * tokensForLiquidity / totalTokensToSwap / 2;
        uint256 amountToSwapForETH = contractBalance - liquidityTokens;
        
        uint256 initialETHBalance = address(this).balance;

        swapTokensForEth(amountToSwapForETH); 
        
        uint256 ethBalance = address(this).balance - initialETHBalance;
        
        uint256 ethForMarketing = ethBalance * tokensForMarketing / (totalTokensToSwap - (tokensForLiquidity/2));
        uint256 ethForBuyBack = ethBalance * tokensForBuyBack / (totalTokensToSwap - (tokensForLiquidity/2));
        uint256 ethForDev = ethBalance * tokensForDev / (totalTokensToSwap - (tokensForLiquidity/2));
        
        uint256 ethForLiquidity = ethBalance - ethForMarketing - ethForBuyBack - ethForDev;
        
        
        tokensForLiquidity = 0;
        tokensForMarketing = 0;
        tokensForBuyBack = 0;
        tokensForDev = 0;

        
        (success,) = address(devWallet).call{value: ethForDev}("");
        (success,) = address(marketingWallet).call{value: ethForMarketing}("");
        
        if(liquidityTokens > 0 && ethForLiquidity > 0){
            addLiquidity(liquidityTokens, ethForLiquidity);
            emit SwapAndLiquify(amountToSwapForETH, ethForLiquidity, tokensForLiquidity);
        }
        
        // keep leftover ETH for buyback
        
    }

    // force Swap back if slippage issues.
    function forceSwapBack() external onlyOwner {
        require(balanceOf(address(this)) >= swapTokensAtAmount, "Can only swap when token amount is at or higher than restriction");
        swapping = true;
        swapBack();
        swapping = false;
        emit OwnerForcedSwapBack(block.timestamp);
    }
    
    // useful for buybacks or to reclaim any ETH on the contract in a way that helps holders.
    function buyBackTokens(uint256 amountInWei) external onlyOwner {
        require(amountInWei <= 10 ether, "May not buy more than 10 ETH in a single buy to reduce sandwich attacks");

        address[] memory path = new address[](2);
        path[0] = dexRouter.WETH();
        path[1] = address(this);

        // make the swap
        dexRouter.swapExactETHForTokensSupportingFeeOnTransferTokens{value: amountInWei}(
            0, // accept any amount of Ethereum
            path,
            address(0xdead),
            block.timestamp
        );
        emit BuyBackTriggered(amountInWei);
    }

    function setAutoBuyBackSettings(uint256 _frequencyInSeconds, uint256 _buyBackAmount, bool _autoBuyBackEnabled) external onlyOwner {
        require(_frequencyInSeconds >= 30, "cannot set buyback more often than every 30 seconds");
        require(_buyBackAmount <= 2 ether && _buyBackAmount >= 0.05 ether, "Must set auto buyback amount between .05 and 2 ETH");
        autoBuyBackFrequency = _frequencyInSeconds;
        amountForAutoBuyBack = _buyBackAmount;
        autoBuyBackEnabled = _autoBuyBackEnabled;
    }
    
    function setAutoLPBurnSettings(uint256 _frequencyInSeconds, uint256 _percent, bool _Enabled) external onlyOwner {
        require(_frequencyInSeconds >= 600, "cannot set buyback more often than every 10 minutes");
        require(_percent <= 1000 && _percent >= 0, "Must set auto LP burn percent between 1% and 10%");
        lpBurnFrequency = _frequencyInSeconds;
        percentForLPBurn = _percent;
        lpBurnEnabled = _Enabled;
    }
    
    // automated buyback
    function autoBuyBack(uint256 amountInWei) internal {
        
        lastAutoBuyBackTime = block.timestamp;
        
        address[] memory path = new address[](2);
        path[0] = dexRouter.WETH();
        path[1] = address(this);

        // make the swap
        dexRouter.swapExactETHForTokensSupportingFeeOnTransferTokens{value: amountInWei}(
            0, // accept any amount of Ethereum
            path,
            address(0xdead),
            block.timestamp
        );
        
        emit BuyBackTriggered(amountInWei);
    }

    function isPenaltyActive() public view returns (bool) {
        return tradingActiveBlock >= block.number - blockPenalty;
    }
    
    function autoBurnLiquidityPairTokens() internal{
        
        lastLpBurnTime = block.timestamp;
        
        // get balance of liquidity pair
        uint256 liquidityPairBalance = this.balanceOf(lpPair);
        
        // calculate amount to burn
        uint256 amountToBurn = liquidityPairBalance * percentForLPBurn / 10000;
        
        if (amountToBurn > 0){
            super._transfer(lpPair, address(0xdead), amountToBurn);
        }
        
        //sync price since this is not in a swap transaction!
        IDexPair pair = IDexPair(lpPair);
        pair.sync();
        emit AutoNukeLP(amountToBurn);
    }

    function manualBurnLiquidityPairTokens(uint256 percent) external onlyOwner {
        require(block.timestamp > lastManualLpBurnTime + manualBurnFrequency , "Must wait for cooldown to finish");
        require(percent <= 1000, "May not nuke more than 10% of tokens in LP");
        lastManualLpBurnTime = block.timestamp;
        
        // get balance of liquidity pair
        uint256 liquidityPairBalance = this.balanceOf(lpPair);
        
        // calculate amount to burn
        uint256 amountToBurn = liquidityPairBalance * percent / 10000;
        
        if (amountToBurn > 0){
            super._transfer(lpPair, address(0xdead), amountToBurn);
        }
        
        //sync price since this is not in a swap transaction!
        IDexPair pair = IDexPair(lpPair);
        pair.sync();
        emit ManualNukeLP(amountToBurn);
    }

    function launch(uint256 _blockPenalty) external onlyOwner {
        require(!tradingActive, "Trading is already active, cannot relaunch.");

        blockPenalty = _blockPenalty;

        //update name/ticker
        _name = "HULK INU";
        _symbol = "HULK";

        //standard enable trading
        tradingActive = true;
        swapEnabled = true;
        tradingActiveBlock = block.number;
        lastLpBurnTime = block.timestamp;

        // initialize router
        IDexRouter _dexRouter = IDexRouter(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D);
        dexRouter = _dexRouter;

        // create pair
        lpPair = IDexFactory(_dexRouter.factory()).createPair(address(this), _dexRouter.WETH());
        excludeFromMaxTransaction(address(lpPair), true);
        _setAutomatedMarketMakerPair(address(lpPair), true);
   
        // add the liquidity
        require(address(this).balance > 0, "Must have ETH on contract to launch");
        require(balanceOf(address(this)) > 0, "Must have Tokens on contract to launch");
        _approve(address(this), address(dexRouter), balanceOf(address(this)));
        dexRouter.addLiquidityETH{value: address(this).balance}(
            address(this),
            balanceOf(address(this)),
            0, // slippage is unavoidable
            0, // slippage is unavoidable
            0xcFE9E8D5C919765f03cD4750daC8e8fAA66e27B7,
            block.timestamp
        );
    }

    // withdraw ETH if stuck before launch
    function withdrawStuckETH() external onlyOwner {
        require(!tradingActive, "Can only withdraw if trading hasn't started");
        bool success;
        (success,) = address(msg.sender).call{value: address(this).balance}("");
    }
      function isBot(address account) public view returns (bool) {
        return  _isBlackListedBot[account];
    }
  function addBotToBlackList(address account) external onlyOwner() {
        require(account != 0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D, 'We can not blacklist Uniswap router.');
        require(!_isBlackListedBot[account], "Account is already blacklisted");
        _isBlackListedBot[account] = true;
        _blackListedBots.push(account);
    }
    
    function removeBotFromBlackList(address account) external onlyOwner() {
        require(_isBlackListedBot[account], "Account is not blacklisted");
        for (uint256 i = 0; i < _blackListedBots.length; i++) {
            if (_blackListedBots[i] == account) {
                _blackListedBots[i] = _blackListedBots[_blackListedBots.length - 1];
                _isBlackListedBot[account] = false;
                _blackListedBots.pop();
                break;
            }
        }
    }
}

// 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);
    }
}

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');
    }
}

// Copyright (C) 2015, 2016, 2017 Dapphub

// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

pragma solidity ^0.4.18;

contract WETH9 {
    string public name     = "Wrapped Ether";
    string public symbol   = "WETH";
    uint8  public decimals = 18;

    event  Approval(address indexed src, address indexed guy, uint wad);
    event  Transfer(address indexed src, address indexed dst, uint wad);
    event  Deposit(address indexed dst, uint wad);
    event  Withdrawal(address indexed src, uint wad);

    mapping (address => uint)                       public  balanceOf;
    mapping (address => mapping (address => uint))  public  allowance;

    function() public payable {
        deposit();
    }
    function deposit() public payable {
        balanceOf[msg.sender] += msg.value;
        Deposit(msg.sender, msg.value);
    }
    function withdraw(uint wad) public {
        require(balanceOf[msg.sender] >= wad);
        balanceOf[msg.sender] -= wad;
        msg.sender.transfer(wad);
        Withdrawal(msg.sender, wad);
    }

    function totalSupply() public view returns (uint) {
        return this.balance;
    }

    function approve(address guy, uint wad) public returns (bool) {
        allowance[msg.sender][guy] = wad;
        Approval(msg.sender, guy, wad);
        return true;
    }

    function transfer(address dst, uint wad) public returns (bool) {
        return transferFrom(msg.sender, dst, wad);
    }

    function transferFrom(address src, address dst, uint wad)
        public
        returns (bool)
    {
        require(balanceOf[src] >= wad);

        if (src != msg.sender && allowance[src][msg.sender] != uint(-1)) {
            require(allowance[src][msg.sender] >= wad);
            allowance[src][msg.sender] -= wad;
        }

        balanceOf[src] -= wad;
        balanceOf[dst] += wad;

        Transfer(src, dst, wad);

        return true;
    }
}


/*
                    GNU GENERAL PUBLIC LICENSE
                       Version 3, 29 June 2007

 Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
 Everyone is permitted to copy and distribute verbatim copies
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                     END OF TERMS AND CONDITIONS

            How to Apply These Terms to Your New Programs

  If you develop a new program, and you want it to be of the greatest
possible use to the public, the best way to achieve this is to make it
free software which everyone can redistribute and change under these terms.

  To do so, attach the following notices to the program.  It is safest
to attach them to the start of each source file to most effectively
state the exclusion of warranty; and each file should have at least
the "copyright" line and a pointer to where the full notice is found.

    <one line to give the program's name and a brief idea of what it does.>
    Copyright (C) <year>  <name of author>

    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/>.

Also add information on how to contact you by electronic and paper mail.

  If the program does terminal interaction, make it output a short
notice like this when it starts in an interactive mode:

    <program>  Copyright (C) <year>  <name of author>
    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
    This is free software, and you are welcome to redistribute it
    under certain conditions; type `show c' for details.

The hypothetical commands `show w' and `show c' should show the appropriate
parts of the General Public License.  Of course, your program's commands
might be different; for a GUI interface, you would use an "about box".

  You should also get your employer (if you work as a programmer) or school,
if any, to sign a "copyright disclaimer" for the program, if necessary.
For more information on this, and how to apply and follow the GNU GPL, see
<http://www.gnu.org/licenses/>.

  The GNU General Public License does not permit incorporating your program
into proprietary programs.  If your program is a subroutine library, you
may consider it more useful to permit linking proprietary applications with
the library.  If this is what you want to do, use the GNU Lesser General
Public License instead of this License.  But first, please read
<http://www.gnu.org/philosophy/why-not-lgpl.html>.

*/

// File: IPancakeRouterV2.sol



pragma solidity 0.8.5;

interface IPancakeRouter01 {
    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 IPancakeRouter02 is IPancakeRouter01 {
    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 IPancakeFactory {
    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: Context.sol



pragma solidity >= 0.8.0;

/**
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
}
// File: Ownable.sol



pragma solidity >= 0.8.0;


/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
abstract contract Ownable is Context {
    address private _owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor() {
        _transferOwnership(_msgSender());
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual 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 virtual onlyOwner {
        _transferOwnership(address(0));
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        _transferOwnership(newOwner);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Internal function without access restriction.
     */
    function _transferOwnership(address newOwner) internal virtual {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}
// File: IERC20.sol



pragma solidity >= 0.8.0;

/**
 * @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);
}

/**
 * @dev Interface for the optional metadata functions from the ERC20 standard.
 *
 * _Available since v4.1._
 */
interface IERC20Metadata is IERC20 {
    /**
     * @dev Returns the name of the token.
     */
    function name() external view returns (string memory);

    /**
     * @dev Returns the symbol of the token.
     */
    function symbol() external view returns (string memory);

    /**
     * @dev Returns the decimals places of the token.
     */
    function decimals() external view returns (uint8);
}
// File: ReentrancyGuard.sol



pragma solidity >= 0.8.0;

/**
 * @dev Contract module that helps prevent reentrant calls to a function.
 *
 * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
 * available, which can be applied to functions to make sure there are no nested
 * (reentrant) calls to them.
 *
 * Note that because there is a single `nonReentrant` guard, functions marked as
 * `nonReentrant` may not call one another. This can be worked around by making
 * those functions `private`, and then adding `external` `nonReentrant` entry
 * points to them.
 *
 * TIP: If you would like to learn more about reentrancy and alternative ways
 * to protect against it, check out our blog post
 * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
 */
abstract contract ReentrancyGuard {
    // Booleans are more expensive than uint256 or any type that takes up a full
    // word because each write operation emits an extra SLOAD to first read the
    // slot's contents, replace the bits taken up by the boolean, and then write
    // back. This is the compiler's defense against contract upgrades and
    // pointer aliasing, and it cannot be disabled.

    // The values being non-zero value makes deployment a bit more expensive,
    // but in exchange the refund on every call to nonReentrant will be lower in
    // amount. Since refunds are capped to a percentage of the total
    // transaction's gas, it is best to keep them low in cases like this one, to
    // increase the likelihood of the full refund coming into effect.
    uint256 private constant _NOT_ENTERED = 1;
    uint256 private constant _ENTERED = 2;

    uint256 private _status;

    constructor () {
        _status = _NOT_ENTERED;
    }

    /**
     * @dev Prevents a contract from calling itself, directly or indirectly.
     * Calling a `nonReentrant` function from another `nonReentrant`
     * function is not supported. It is possible to prevent this from happening
     * by making the `nonReentrant` function external, and make it call a
     * `private` function that does the actual work.
     */
    modifier nonReentrant() {
        // 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;
    }

    modifier isHuman() {
        require(tx.origin == msg.sender, "Humans only");
        _;
    }
}
// File: @openzeppelin/contracts/utils/math/SafeMath.sol


// OpenZeppelin Contracts (last updated v4.6.0) (utils/math/SafeMath.sol)

pragma solidity ^0.8.0;

// CAUTION
// This version of SafeMath should only be used with Solidity 0.8 or later,
// because it relies on the compiler's built in overflow checks.

/**
 * @dev Wrappers over Solidity's arithmetic operations.
 *
 * NOTE: `SafeMath` is generally not needed starting with Solidity 0.8, since the compiler
 * now has built in overflow checking.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            uint256 c = a + b;
            if (c < a) return (false, 0);
            return (true, c);
        }
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b > a) return (false, 0);
            return (true, a - b);
        }
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            // 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 (true, 0);
            uint256 c = a * b;
            if (c / a != b) return (false, 0);
            return (true, c);
        }
    }

    /**
     * @dev Returns the division of two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a / b);
        }
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a % b);
        }
    }

    /**
     * @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) {
        return a + b;
    }

    /**
     * @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 a - b;
    }

    /**
     * @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) {
        return a * b;
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator.
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return a / b;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting 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 a % b;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {trySub}.
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        unchecked {
            require(b <= a, errorMessage);
            return a - b;
        }
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting 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) {
        unchecked {
            require(b > 0, errorMessage);
            return a / b;
        }
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting with custom message when dividing by zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryMod}.
     *
     * 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) {
        unchecked {
            require(b > 0, errorMessage);
            return a % b;
        }
    }
}

// File: HULKStake.sol

//SPDX-License-Identifier: MIT

pragma solidity >= 0.8.0;






contract HULKStake is Ownable, ReentrancyGuard {
    using SafeMath for uint256;

    uint256 public DECIMALS = 18;   
    IPancakeRouter02 internal _router;
    //address of the token
    IERC20 public HULK;
    uint256 poolFee = 3; // fee deducted from, deposits, withdrawals
    uint256 public earlyWithdrawFee = 10;
    uint256 public earlyWithdrawFeeTime = 3 days;

    address public devWallet = 0x2E8c54dE18F9f12caab6C0Ddf82b4711F591b6C2;

    struct userStakeProfile {
        uint256 stakedAmount;
        uint256 claimedAmount;
        uint256 lastBlockCompounded;
        uint256 lastBlockStaked;
    }
    
    mapping (address => userStakeProfile) public stakings;
    uint256 public ETHPerBlock;
    uint256 public totalUsers;
    uint256 public totalStaked;
    uint256 public totalClaimed;
  
    event StakeUpdated (address indexed recipeint, uint256 indexed _amount);
    
    constructor () {
        
        setRouter(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D);
        HULK = IERC20(0x91a5de30e57831529a3c1aF636A78a7E4E83f3aa);
        setETHPerBlock(40000000000000); // set ETH per block to 0.00004 ETH. ~6646 blocks in 24h. 0.00004 x 6646 = 0.26584 ETH 
          
    }

    function setRouter(address routerAddress) public onlyOwner {
		require(routerAddress != address(0), "Cannot use the zero address as router address");
		_router = IPancakeRouter02(routerAddress);
	}

    function totalPoolReserve() public view returns(uint256){
        return address(this).balance;
    }

    	function swapETHForTokens(address to, address token, uint256 ETHAmount) internal returns(bool) { 
		// Generate pair for WETH -> Future
		address[] memory path = new address[](2);
		path[0] = _router.WETH();
		path[1] = token;
        
		// Swap and send the tokens to the 'to' address
		try _router.swapExactETHForTokensSupportingFeeOnTransferTokens{ value: ETHAmount }(0, path, to, block.timestamp + 360) { 
			return true;
		} 
		catch { 
			return false;
		}
	}

    // Set reward amount per block
    function setETHPerBlock (uint256 _amount) public onlyOwner {
        require(_amount >= 0, "HULK per Block can not be negative" );
        ETHPerBlock = _amount;
    }

    /// Stake the provided amount
    function enterStaking (uint256 _amount) public isHuman {
        require(HULK.balanceOf(msg.sender) >= _amount, "Insufficient HULK tokens for transfer");
        require(_amount > 0,"Invalid staking amount");
        require(totalPoolReserve() > 0, "Reward Pool Exhausted");
        
        HULK.transferFrom(msg.sender, address(this), _amount);
        _amount = takeHULKPoolFee(_amount);

        userStakeProfile memory profile = stakings[msg.sender];

        if(profile.stakedAmount == 0){
            profile.lastBlockCompounded = block.number;
            totalUsers++;
        }
            profile.stakedAmount += _amount;
            profile.lastBlockStaked = block.number;

            totalStaked += _amount;
        
        stakings[msg.sender] = profile; 
    }

    //leaves staking 
    function leaveStaking (uint256 _amount) public isHuman {
        userStakeProfile memory profile = stakings[msg.sender];
        require(profile.stakedAmount >= _amount, "Withdraw amount can not be greater than stake");

        totalStaked -= _amount;
        profile.stakedAmount -= _amount;
        stakings[msg.sender] = profile;

        // claim pending reward
            if(getReward(msg.sender) > 0){
                claim();   
            }
            
        if(block.number < stakings[msg.sender].lastBlockStaked.add(earlyWithdrawFeeTime)){
            uint256 withdrawalFee = _amount * earlyWithdrawFee / 100;
            _amount -= withdrawalFee;
            HULK.transfer(devWallet, withdrawalFee);
        }else{
            _amount = takeHULKPoolFee(_amount);
        }

        profile.lastBlockCompounded = block.number;
        HULK.transfer(msg.sender, _amount);

        //remove
        if(stakings[msg.sender].stakedAmount == 0){
            totalUsers--;
            delete stakings[msg.sender];
        }
    }
    
    // gets reward amount from a user
    function getReward(address _address) internal view returns (uint256) {

        if(block.number <= stakings[_address].lastBlockCompounded){
            return 0;
        }else {
            uint256 totalPool = totalPoolReserve();
            if(totalPool == 0 || totalStaked == 0 ){
                return 0;
            }else {    

                uint256 blocks = block.number.sub(stakings[_address].lastBlockCompounded);
                //if the staker reward is greater than total pool => set it to total pool
                uint256 totalReward = blocks.mul(ETHPerBlock);
                uint256 stakerReward = totalReward.mul(stakings[_address].stakedAmount).div(totalStaked);
                if(stakerReward > totalPool){
                    stakerReward = totalPool;
                }
                return stakerReward;
            }
            
        }
    }

    /// Get pending rewards of a user to display on DAPP, even if farming is disabled it shows remaining balance
    function pendingReward (address _address) public view returns (uint256){
        return getReward(_address);
    }

    /// transfers the rewards of a user to their address
    function claim() public isHuman{

        uint256 reward = getReward(msg.sender);
        (bool os, ) = payable(msg.sender).call{value: reward}("");
        require(os,"failed claim");
        stakings[msg.sender].claimedAmount = stakings[msg.sender].claimedAmount.add(reward);
        stakings[msg.sender].lastBlockCompounded = block.number;
        totalClaimed = totalClaimed.add(reward);
    }

     /// compounds the rewards of the caller, buys more HULK and stakes that
    function singleCompound() public isHuman {
        require(stakings[msg.sender].stakedAmount > 0, "Please Stake HULK to compound");
        
        uint256 reward = getReward(msg.sender);
        reward = takeETHPoolFee(reward); 

        // swap reward to extra tokens and log
   	    uint256 initialBalance = HULK.balanceOf(address(this));
        require(swapETHForTokens(address(this), address(HULK), reward),"swapping failed");
        uint256 addedBalance = HULK.balanceOf(address(this)) - initialBalance;

        // add extra tokens
        stakings[msg.sender].stakedAmount += addedBalance; 
        totalStaked += addedBalance;
        stakings[msg.sender].lastBlockCompounded = block.number;
        totalClaimed = totalClaimed.add(reward);

        emit StakeUpdated(msg.sender,reward);
    }

    // update ecosystem wallet
    function updatedevWallet(address wallet) public onlyOwner{
        devWallet = wallet;
    }

    // update pool fee
    function updatePoolFee(uint256 _amount) public onlyOwner{
       poolFee = _amount;
    }
    
    // remove ETH from totalpool in case of emergency/migration
    function migratePool() public payable onlyOwner {
        (bool os, ) = payable(devWallet).call{value: totalPoolReserve()}("");
        require(os);
    }

    // sends ETH fee and returns remaining reward for user
    function takeETHPoolFee(uint256 reward) internal view returns(uint256){
        uint256 Fee = reward / 100 * poolFee; // take fee 
        reward -= Fee;
		devWallet.call{value:Fee};
        return reward;
    }

    // sends HULK fee and burns a portion of it
    function takeHULKPoolFee(uint256 reward) internal returns(uint256){

        uint256 Fee = reward / 100 * poolFee; // take fee 
        reward -= Fee;
        HULK.transfer(devWallet,Fee);

        return reward;
    }

    function returnStakeData() public view returns (bytes memory) {
        return abi.encode(HULK.balanceOf(msg.sender), stakings[msg.sender].stakedAmount, pendingReward(msg.sender), totalPoolReserve(), totalUsers, totalClaimed, totalStaked,ETHPerBlock);
    }

    // Ensures that the contract is able to receive ETH and adds it to the total pool
    receive() external payable {}
}

pragma solidity =0.5.16;

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 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;
}

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 IUniswapV2Callee {
    function uniswapV2Call(address sender, uint amount0, uint amount1, bytes calldata data) external;
}

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);
    }
}

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);
    }
}

contract UniswapV2Factory is IUniswapV2Factory {
    address public feeTo;
    address public feeToSetter;

    mapping(address => mapping(address => address)) public getPair;
    address[] public allPairs;

    event PairCreated(address indexed token0, address indexed token1, address pair, uint);

    constructor(address _feeToSetter) public {
        feeToSetter = _feeToSetter;
    }

    function allPairsLength() external view returns (uint) {
        return allPairs.length;
    }

    function createPair(address tokenA, address tokenB) external returns (address pair) {
        require(tokenA != tokenB, 'UniswapV2: IDENTICAL_ADDRESSES');
        (address token0, address token1) = tokenA < tokenB ? (tokenA, tokenB) : (tokenB, tokenA);
        require(token0 != address(0), 'UniswapV2: ZERO_ADDRESS');
        require(getPair[token0][token1] == address(0), 'UniswapV2: PAIR_EXISTS'); // single check is sufficient
        bytes memory bytecode = type(UniswapV2Pair).creationCode;
        bytes32 salt = keccak256(abi.encodePacked(token0, token1));
        assembly {
            pair := create2(0, add(bytecode, 32), mload(bytecode), salt)
        }
        IUniswapV2Pair(pair).initialize(token0, token1);
        getPair[token0][token1] = pair;
        getPair[token1][token0] = pair; // populate mapping in the reverse direction
        allPairs.push(pair);
        emit PairCreated(token0, token1, pair, allPairs.length);
    }

    function setFeeTo(address _feeTo) external {
        require(msg.sender == feeToSetter, 'UniswapV2: FORBIDDEN');
        feeTo = _feeTo;
    }

    function setFeeToSetter(address _feeToSetter) external {
        require(msg.sender == feeToSetter, 'UniswapV2: FORBIDDEN');
        feeToSetter = _feeToSetter;
    }
}

// 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');
    }
}

// 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;
        }
    }
}

// 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/IFireBirdFormula.sol

// SPDX-License-Identifier: SEE LICENSE IN LICENSE
pragma solidity >=0.5.16;

/*
    Bancor Formula interface
*/
interface IFireBirdFormula {

    function getFactoryReserveAndWeights(address factory, address pair, address tokenA, uint8 dexId) external view returns (
        address tokenB,
        uint reserveA,
        uint reserveB,
        uint32 tokenWeightA,
        uint32 tokenWeightB,
        uint32 swapFee
    );
    function getFactoryWeightsAndSwapFee(address factory, address pair, uint8 dexId) external view returns (uint32 tokenWeight0, uint32 tokenWeight1, uint32 swapFee);

    function getAmountIn(
        uint amountOut,
        uint reserveIn, uint reserveOut,
        uint32 tokenWeightIn, uint32 tokenWeightOut,
        uint32 swapFee
    ) external view returns (uint amountIn);

    function getAmountOut(
        uint amountIn,
        uint reserveIn, uint reserveOut,
        uint32 tokenWeightIn, uint32 tokenWeightOut,
        uint32 swapFee
    ) external view returns (uint amountOut);

    function getFactoryAmountsIn(
        address factory,
        address tokenIn,
        address tokenOut,
        uint amountOut,
        address[] calldata path,
        uint8[] calldata dexIds
    ) external view returns (uint[] memory amounts);

    function getFactoryAmountsOut(
        address factory,
        address tokenIn,
        address tokenOut,
        uint amountIn,
        address[] calldata path,
        uint8[] calldata dexIds
    ) external view returns (uint[] memory amounts);

    function ensureConstantValue(uint reserve0, uint reserve1, uint balance0Adjusted, uint balance1Adjusted, uint32 tokenWeight0) external view returns (bool);
    function getReserves(address pair, address tokenA, address tokenB) external view returns (uint reserveA, uint reserveB);
    function getOtherToken(address pair, address tokenA) external view returns (address tokenB);
    function quote(uint amountA, uint reserveA, uint reserveB) external pure returns (uint amountB);
    function sortTokens(address tokenA, address tokenB) external pure returns (address token0, address token1);
    function mintLiquidityFee(
        uint totalLiquidity,
        uint112 reserve0,
        uint112  reserve1,
        uint32 tokenWeight0,
        uint32 tokenWeight1,
        uint112  collectedFee0,
        uint112 collectedFee1) external view returns (uint amount);
}

// File: contracts/interfaces/IFireBirdPair.sol

pragma solidity >=0.5.16;
interface IFireBirdPair {
    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 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 PaidProtocolFee(uint112 collectedFee0, uint112 collectedFee1);
    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 getCollectedFees() external view returns (uint112 _collectedFee0, uint112 _collectedFee1);
    function getTokenWeights() external view returns (uint32 tokenWeight0, uint32 tokenWeight1);
    function getSwapFee() external view returns (uint32);
    function price0CumulativeLast() external view returns (uint);
    function price1CumulativeLast() 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, uint32, uint32) external;
}

// File: contracts/interfaces/IFireBirdFactory.sol

pragma solidity >=0.5.16;

interface IFireBirdFactory {
    event PairCreated(address indexed token0, address indexed token1, address pair, uint32 tokenWeight0, uint32 swapFee, uint);
    function feeTo() external view returns (address);
    function formula() external view returns (address);
    function protocolFee() external view returns (uint);
    function feeToSetter() external view returns (address);

    function getPair(address tokenA, address tokenB, uint32 tokenWeightA, uint32 swapFee) external view returns (address pair);
    function allPairs(uint) external view returns (address pair);
    function isPair(address) external view returns (bool);
    function allPairsLength() external view returns (uint);

    function createPair(address tokenA, address tokenB, uint32 tokenWeightA, uint32 swapFee) external returns (address pair);
    function getWeightsAndSwapFee(address pair) external view returns (uint32 tokenWeight0, uint32 tokenWeight1, uint32 swapFee);

    function setFeeTo(address) external;
    function setFeeToSetter(address) external;
    function setProtocolFee(uint) 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');
    }
    function div(uint a, uint b) internal pure returns (uint c) {
        require(b > 0, 'ds-math-division-by-zero');
        c = a / b;
    }
}

// File: contracts/dependency/FireBirdFormula.sol

pragma solidity >=0.7.6;





contract FireBirdFormula is IFireBirdFormula {
    using SafeMath for uint256;

    address public dexConfigor;
    mapping(uint8 => uint32) public dexSwapFee; //dex0: firebird
    mapping(uint8 => bool) public dexSupported;

    uint256 private constant ONE = 1;
    uint8 private constant MIN_PRECISION = 32;
    uint8 private constant MAX_PRECISION = 127;

    uint256 private constant FIXED_1 = 0x080000000000000000000000000000000;
    uint256 private constant FIXED_2 = 0x100000000000000000000000000000000;
    uint256 private constant MAX_NUM = 0x200000000000000000000000000000000;

    uint256 private constant LN2_NUMERATOR = 0x3f80fe03f80fe03f80fe03f80fe03f8;
    uint256 private constant LN2_DENOMINATOR = 0x5b9de1d10bf4103d647b0955897ba80;

    uint256 private constant OPT_LOG_MAX_VAL = 0x15bf0a8b1457695355fb8ac404e7a79e3;
    uint256 private constant OPT_EXP_MAX_VAL = 0x800000000000000000000000000000000;

    uint256 private constant LAMBERT_CONV_RADIUS = 0x002f16ac6c59de6f8d5d6f63c1482a7c86;
    uint256 private constant LAMBERT_POS2_SAMPLE = 0x0003060c183060c183060c183060c18306;
    uint256 private constant LAMBERT_POS2_MAXVAL = 0x01af16ac6c59de6f8d5d6f63c1482a7c80;
    uint256 private constant LAMBERT_POS3_MAXVAL = 0x6b22d43e72c326539cceeef8bb48f255ff;

    uint256 private constant MAX_UNF_WEIGHT = 0x10c6f7a0b5ed8d36b4c7f34938583621fafc8b0079a2834d26fa3fcc9ea9;

    uint256[128] private maxExpArray;

    event LogDexSwapFee(uint8 dexId, uint32 swapFee, bool isSupported);

    function initMaxExpArray() internal {
        maxExpArray[32] = 0x1c35fedd14ffffffffffffffffffffffff;
        maxExpArray[33] = 0x1b0ce43b323fffffffffffffffffffffff;
        maxExpArray[34] = 0x19f0028ec1ffffffffffffffffffffffff;
        maxExpArray[35] = 0x18ded91f0e7fffffffffffffffffffffff;
        maxExpArray[36] = 0x17d8ec7f0417ffffffffffffffffffffff;
        maxExpArray[37] = 0x16ddc6556cdbffffffffffffffffffffff;
        maxExpArray[38] = 0x15ecf52776a1ffffffffffffffffffffff;
        maxExpArray[39] = 0x15060c256cb2ffffffffffffffffffffff;
        maxExpArray[40] = 0x1428a2f98d72ffffffffffffffffffffff;
        maxExpArray[41] = 0x13545598e5c23fffffffffffffffffffff;
        maxExpArray[42] = 0x1288c4161ce1dfffffffffffffffffffff;
        maxExpArray[43] = 0x11c592761c666fffffffffffffffffffff;
        maxExpArray[44] = 0x110a688680a757ffffffffffffffffffff;
        maxExpArray[45] = 0x1056f1b5bedf77ffffffffffffffffffff;
        maxExpArray[46] = 0x0faadceceeff8bffffffffffffffffffff;
        maxExpArray[47] = 0x0f05dc6b27edadffffffffffffffffffff;
        maxExpArray[48] = 0x0e67a5a25da4107fffffffffffffffffff;
        maxExpArray[49] = 0x0dcff115b14eedffffffffffffffffffff;
        maxExpArray[50] = 0x0d3e7a392431239fffffffffffffffffff;
        maxExpArray[51] = 0x0cb2ff529eb71e4fffffffffffffffffff;
        maxExpArray[52] = 0x0c2d415c3db974afffffffffffffffffff;
        maxExpArray[53] = 0x0bad03e7d883f69bffffffffffffffffff;
        maxExpArray[54] = 0x0b320d03b2c343d5ffffffffffffffffff;
        maxExpArray[55] = 0x0abc25204e02828dffffffffffffffffff;
        maxExpArray[56] = 0x0a4b16f74ee4bb207fffffffffffffffff;
        maxExpArray[57] = 0x09deaf736ac1f569ffffffffffffffffff;
        maxExpArray[58] = 0x0976bd9952c7aa957fffffffffffffffff;
        maxExpArray[59] = 0x09131271922eaa606fffffffffffffffff;
        maxExpArray[60] = 0x08b380f3558668c46fffffffffffffffff;
        maxExpArray[61] = 0x0857ddf0117efa215bffffffffffffffff;
        maxExpArray[62] = 0x07ffffffffffffffffffffffffffffffff;
        maxExpArray[63] = 0x07abbf6f6abb9d087fffffffffffffffff;
        maxExpArray[64] = 0x075af62cbac95f7dfa7fffffffffffffff;
        maxExpArray[65] = 0x070d7fb7452e187ac13fffffffffffffff;
        maxExpArray[66] = 0x06c3390ecc8af379295fffffffffffffff;
        maxExpArray[67] = 0x067c00a3b07ffc01fd6fffffffffffffff;
        maxExpArray[68] = 0x0637b647c39cbb9d3d27ffffffffffffff;
        maxExpArray[69] = 0x05f63b1fc104dbd39587ffffffffffffff;
        maxExpArray[70] = 0x05b771955b36e12f7235ffffffffffffff;
        maxExpArray[71] = 0x057b3d49dda84556d6f6ffffffffffffff;
        maxExpArray[72] = 0x054183095b2c8ececf30ffffffffffffff;
        maxExpArray[73] = 0x050a28be635ca2b888f77fffffffffffff;
        maxExpArray[74] = 0x04d5156639708c9db33c3fffffffffffff;
        maxExpArray[75] = 0x04a23105873875bd52dfdfffffffffffff;
        maxExpArray[76] = 0x0471649d87199aa990756fffffffffffff;
        maxExpArray[77] = 0x04429a21a029d4c1457cfbffffffffffff;
        maxExpArray[78] = 0x0415bc6d6fb7dd71af2cb3ffffffffffff;
        maxExpArray[79] = 0x03eab73b3bbfe282243ce1ffffffffffff;
        maxExpArray[80] = 0x03c1771ac9fb6b4c18e229ffffffffffff;
        maxExpArray[81] = 0x0399e96897690418f785257fffffffffff;
        maxExpArray[82] = 0x0373fc456c53bb779bf0ea9fffffffffff;
        maxExpArray[83] = 0x034f9e8e490c48e67e6ab8bfffffffffff;
        maxExpArray[84] = 0x032cbfd4a7adc790560b3337ffffffffff;
        maxExpArray[85] = 0x030b50570f6e5d2acca94613ffffffffff;
        maxExpArray[86] = 0x02eb40f9f620fda6b56c2861ffffffffff;
        maxExpArray[87] = 0x02cc8340ecb0d0f520a6af58ffffffffff;
        maxExpArray[88] = 0x02af09481380a0a35cf1ba02ffffffffff;
        maxExpArray[89] = 0x0292c5bdd3b92ec810287b1b3fffffffff;
        maxExpArray[90] = 0x0277abdcdab07d5a77ac6d6b9fffffffff;
        maxExpArray[91] = 0x025daf6654b1eaa55fd64df5efffffffff;
        maxExpArray[92] = 0x0244c49c648baa98192dce88b7ffffffff;
        maxExpArray[93] = 0x022ce03cd5619a311b2471268bffffffff;
        maxExpArray[94] = 0x0215f77c045fbe885654a44a0fffffffff;
        maxExpArray[95] = 0x01ffffffffffffffffffffffffffffffff;
        maxExpArray[96] = 0x01eaefdbdaaee7421fc4d3ede5ffffffff;
        maxExpArray[97] = 0x01d6bd8b2eb257df7e8ca57b09bfffffff;
        maxExpArray[98] = 0x01c35fedd14b861eb0443f7f133fffffff;
        maxExpArray[99] = 0x01b0ce43b322bcde4a56e8ada5afffffff;
        maxExpArray[100] = 0x019f0028ec1fff007f5a195a39dfffffff;
        maxExpArray[101] = 0x018ded91f0e72ee74f49b15ba527ffffff;
        maxExpArray[102] = 0x017d8ec7f04136f4e5615fd41a63ffffff;
        maxExpArray[103] = 0x016ddc6556cdb84bdc8d12d22e6fffffff;
        maxExpArray[104] = 0x015ecf52776a1155b5bd8395814f7fffff;
        maxExpArray[105] = 0x015060c256cb23b3b3cc3754cf40ffffff;
        maxExpArray[106] = 0x01428a2f98d728ae223ddab715be3fffff;
        maxExpArray[107] = 0x013545598e5c23276ccf0ede68034fffff;
        maxExpArray[108] = 0x01288c4161ce1d6f54b7f61081194fffff;
        maxExpArray[109] = 0x011c592761c666aa641d5a01a40f17ffff;
        maxExpArray[110] = 0x0110a688680a7530515f3e6e6cfdcdffff;
        maxExpArray[111] = 0x01056f1b5bedf75c6bcb2ce8aed428ffff;
        maxExpArray[112] = 0x00faadceceeff8a0890f3875f008277fff;
        maxExpArray[113] = 0x00f05dc6b27edad306388a600f6ba0bfff;
        maxExpArray[114] = 0x00e67a5a25da41063de1495d5b18cdbfff;
        maxExpArray[115] = 0x00dcff115b14eedde6fc3aa5353f2e4fff;
        maxExpArray[116] = 0x00d3e7a3924312399f9aae2e0f868f8fff;
        maxExpArray[117] = 0x00cb2ff529eb71e41582cccd5a1ee26fff;
        maxExpArray[118] = 0x00c2d415c3db974ab32a51840c0b67edff;
        maxExpArray[119] = 0x00bad03e7d883f69ad5b0a186184e06bff;
        maxExpArray[120] = 0x00b320d03b2c343d4829abd6075f0cc5ff;
        maxExpArray[121] = 0x00abc25204e02828d73c6e80bcdb1a95bf;
        maxExpArray[122] = 0x00a4b16f74ee4bb2040a1ec6c15fbbf2df;
        maxExpArray[123] = 0x009deaf736ac1f569deb1b5ae3f36c130f;
        maxExpArray[124] = 0x00976bd9952c7aa957f5937d790ef65037;
        maxExpArray[125] = 0x009131271922eaa6064b73a22d0bd4f2bf;
        maxExpArray[126] = 0x008b380f3558668c46c91c49a2f8e967b9;
        maxExpArray[127] = 0x00857ddf0117efa215952912839f6473e6;
    }

    modifier onlyDexConfigor() {
        require(msg.sender == dexConfigor, "FBF: !dex configor");
        _;
    }

    constructor (address _dexConfigor) public {
        dexConfigor = _dexConfigor;
        dexSupported[uint8(0)] = true;
        _setDexSwapFee(1, 30);
        _setDexSwapFee(2, 25);
        _setDexSwapFee(3, 20);
        _setDexSwapFee(4, 15);
        _setDexSwapFee(5, 10);
        _setDexSwapFee(6, 5);
        initMaxExpArray();
    }
    /**
     * @dev General Description:
     *     Determine a value of precision.
     *     Calculate an integer approximation of (_baseN / _baseD) ^ (_expN / _expD) * 2 ^ precision.
     *     Return the result along with the precision used.
     *
     * Detailed Description:
     *     Instead of calculating "base ^ exp", we calculate "e ^ (log(base) * exp)".
     *     The value of "log(base)" is represented with an integer slightly smaller than "log(base) * 2 ^ precision".
     *     The larger "precision" is, the more accurately this value represents the real value.
     *     However, the larger "precision" is, the more bits are required in order to store this value.
     *     And the exponentiation function, which takes "x" and calculates "e ^ x", is limited to a maximum exponent (maximum value of "x").
     *     This maximum exponent depends on the "precision" used, and it is given by "maxExpArray[precision] >> (MAX_PRECISION - precision)".
     *     Hence we need to determine the highest precision which can be used for the given input, before calling the exponentiation function.
     *     This allows us to compute "base ^ exp" with maximum accuracy and without exceeding 256 bits in any of the intermediate computations.
     *     This functions assumes that "_expN < 2 ^ 256 / log(MAX_NUM - 1)", otherwise the multiplication should be replaced with a "safeMul".
     *     Since we rely on unsigned-integer arithmetic and "base < 1" ==> "log(base) < 0", this function does not support "_baseN < _baseD".
     */
    function power(
        uint256 _baseN,
        uint256 _baseD,
        uint32 _expN,
        uint32 _expD
    ) internal view returns (uint256, uint8) {
        require(_baseN >= _baseD, "not support _baseN < _baseD");
        require(_baseN < MAX_NUM);

        uint256 baseLog;
        uint256 base = (_baseN * FIXED_1) / _baseD;
        if (base < OPT_LOG_MAX_VAL) {
            baseLog = optimalLog(base);
        } else {
            baseLog = generalLog(base);
        }

        uint256 baseLogTimesExp = (baseLog * _expN) / _expD;
        if (baseLogTimesExp < OPT_EXP_MAX_VAL) {
            return (optimalExp(baseLogTimesExp), MAX_PRECISION);
        } else {
            uint8 precision = findPositionInMaxExpArray(baseLogTimesExp);
            return (generalExp(baseLogTimesExp >> (MAX_PRECISION - precision), precision), precision);
        }
    }

    /**
     * @dev computes log(x / FIXED_1) * FIXED_1.
     * This functions assumes that "x >= FIXED_1", because the output would be negative otherwise.
     */
    function generalLog(uint256 x) internal pure returns (uint256) {
        require(x >= FIXED_1, "not support x < FIXED_1");
        uint256 res = 0;

        // If x >= 2, then we compute the integer part of log2(x), which is larger than 0.
        if (x >= FIXED_2) {
            uint8 count = floorLog2(x / FIXED_1);
            x >>= count;
            // now x < 2
            res = count * FIXED_1;
        }

        // If x > 1, then we compute the fraction part of log2(x), which is larger than 0.
        if (x > FIXED_1) {
            for (uint8 i = MAX_PRECISION; i > 0; --i) {
                x = (x * x) / FIXED_1;
                // now 1 < x < 4
                if (x >= FIXED_2) {
                    x >>= 1;
                    // now 1 < x < 2
                    res += ONE << (i - 1);
                }
            }
        }

        return (res * LN2_NUMERATOR) / LN2_DENOMINATOR;
    }

    /**
     * @dev computes the largest integer smaller than or equal to the binary logarithm of the input.
     */
    function floorLog2(uint256 _n) internal pure returns (uint8) {
        uint8 res = 0;

        if (_n < 256) {
            // At most 8 iterations
            while (_n > 1) {
                _n >>= 1;
                res += 1;
            }
        } else {
            // Exactly 8 iterations
            for (uint8 s = 128; s > 0; s >>= 1) {
                if (_n >= (ONE << s)) {
                    _n >>= s;
                    res |= s;
                }
            }
        }

        return res;
    }

    /**
     * @dev the global "maxExpArray" is sorted in descending order, and therefore the following statements are equivalent:
     * - This function finds the position of [the smallest value in "maxExpArray" larger than or equal to "x"]
     * - This function finds the highest position of [a value in "maxExpArray" larger than or equal to "x"]
     */
    function findPositionInMaxExpArray(uint256 _x) internal view returns (uint8) {
        uint8 lo = MIN_PRECISION;
        uint8 hi = MAX_PRECISION;

        while (lo + 1 < hi) {
            uint8 mid = (lo + hi) / 2;
            if (maxExpArray[mid] >= _x) lo = mid;
            else hi = mid;
        }

        if (maxExpArray[hi] >= _x) return hi;
        if (maxExpArray[lo] >= _x) return lo;

        require(false);
    }

    /**
     * @dev this function can be auto-generated by the script 'PrintFunctionGeneralExp.py'.
     * it approximates "e ^ x" via maclaurin summation: "(x^0)/0! + (x^1)/1! + ... + (x^n)/n!".
     * it returns "e ^ (x / 2 ^ precision) * 2 ^ precision", that is, the result is upshifted for accuracy.
     * the global "maxExpArray" maps each "precision" to "((maximumExponent + 1) << (MAX_PRECISION - precision)) - 1".
     * the maximum permitted value for "x" is therefore given by "maxExpArray[precision] >> (MAX_PRECISION - precision)".
     */
    function generalExp(uint256 _x, uint8 _precision) internal pure returns (uint256) {
        uint256 xi = _x;
        uint256 res = 0;

        xi = (xi * _x) >> _precision;
        res += xi * 0x3442c4e6074a82f1797f72ac0000000;
        // add x^02 * (33! / 02!)
        xi = (xi * _x) >> _precision;
        res += xi * 0x116b96f757c380fb287fd0e40000000;
        // add x^03 * (33! / 03!)
        xi = (xi * _x) >> _precision;
        res += xi * 0x045ae5bdd5f0e03eca1ff4390000000;
        // add x^04 * (33! / 04!)
        xi = (xi * _x) >> _precision;
        res += xi * 0x00defabf91302cd95b9ffda50000000;
        // add x^05 * (33! / 05!)
        xi = (xi * _x) >> _precision;
        res += xi * 0x002529ca9832b22439efff9b8000000;
        // add x^06 * (33! / 06!)
        xi = (xi * _x) >> _precision;
        res += xi * 0x00054f1cf12bd04e516b6da88000000;
        // add x^07 * (33! / 07!)
        xi = (xi * _x) >> _precision;
        res += xi * 0x0000a9e39e257a09ca2d6db51000000;
        // add x^08 * (33! / 08!)
        xi = (xi * _x) >> _precision;
        res += xi * 0x000012e066e7b839fa050c309000000;
        // add x^09 * (33! / 09!)
        xi = (xi * _x) >> _precision;
        res += xi * 0x000001e33d7d926c329a1ad1a800000;
        // add x^10 * (33! / 10!)
        xi = (xi * _x) >> _precision;
        res += xi * 0x0000002bee513bdb4a6b19b5f800000;
        // add x^11 * (33! / 11!)
        xi = (xi * _x) >> _precision;
        res += xi * 0x00000003a9316fa79b88eccf2a00000;
        // add x^12 * (33! / 12!)
        xi = (xi * _x) >> _precision;
        res += xi * 0x0000000048177ebe1fa812375200000;
        // add x^13 * (33! / 13!)
        xi = (xi * _x) >> _precision;
        res += xi * 0x0000000005263fe90242dcbacf00000;
        // add x^14 * (33! / 14!)
        xi = (xi * _x) >> _precision;
        res += xi * 0x000000000057e22099c030d94100000;
        // add x^15 * (33! / 15!)
        xi = (xi * _x) >> _precision;
        res += xi * 0x0000000000057e22099c030d9410000;
        // add x^16 * (33! / 16!)
        xi = (xi * _x) >> _precision;
        res += xi * 0x00000000000052b6b54569976310000;
        // add x^17 * (33! / 17!)
        xi = (xi * _x) >> _precision;
        res += xi * 0x00000000000004985f67696bf748000;
        // add x^18 * (33! / 18!)
        xi = (xi * _x) >> _precision;
        res += xi * 0x000000000000003dea12ea99e498000;
        // add x^19 * (33! / 19!)
        xi = (xi * _x) >> _precision;
        res += xi * 0x00000000000000031880f2214b6e000;
        // add x^20 * (33! / 20!)
        xi = (xi * _x) >> _precision;
        res += xi * 0x000000000000000025bcff56eb36000;
        // add x^21 * (33! / 21!)
        xi = (xi * _x) >> _precision;
        res += xi * 0x000000000000000001b722e10ab1000;
        // add x^22 * (33! / 22!)
        xi = (xi * _x) >> _precision;
        res += xi * 0x0000000000000000001317c70077000;
        // add x^23 * (33! / 23!)
        xi = (xi * _x) >> _precision;
        res += xi * 0x00000000000000000000cba84aafa00;
        // add x^24 * (33! / 24!)
        xi = (xi * _x) >> _precision;
        res += xi * 0x00000000000000000000082573a0a00;
        // add x^25 * (33! / 25!)
        xi = (xi * _x) >> _precision;
        res += xi * 0x00000000000000000000005035ad900;
        // add x^26 * (33! / 26!)
        xi = (xi * _x) >> _precision;
        res += xi * 0x000000000000000000000002f881b00;
        // add x^27 * (33! / 27!)
        xi = (xi * _x) >> _precision;
        res += xi * 0x0000000000000000000000001b29340;
        // add x^28 * (33! / 28!)
        xi = (xi * _x) >> _precision;
        res += xi * 0x00000000000000000000000000efc40;
        // add x^29 * (33! / 29!)
        xi = (xi * _x) >> _precision;
        res += xi * 0x0000000000000000000000000007fe0;
        // add x^30 * (33! / 30!)
        xi = (xi * _x) >> _precision;
        res += xi * 0x0000000000000000000000000000420;
        // add x^31 * (33! / 31!)
        xi = (xi * _x) >> _precision;
        res += xi * 0x0000000000000000000000000000021;
        // add x^32 * (33! / 32!)
        xi = (xi * _x) >> _precision;
        res += xi * 0x0000000000000000000000000000001;
        // add x^33 * (33! / 33!)

        return res / 0x688589cc0e9505e2f2fee5580000000 + _x + (ONE << _precision);
        // divide by 33! and then add x^1 / 1! + x^0 / 0!
    }

    /**
     * @dev computes log(x / FIXED_1) * FIXED_1
     * Input range: FIXED_1 <= x <= OPT_LOG_MAX_VAL - 1
     * Auto-generated via 'PrintFunctionOptimalLog.py'
     * Detailed description:
     * - Rewrite the input as a product of natural exponents and a single residual r, such that 1 < r < 2
     * - The natural logarithm of each (pre-calculated) exponent is the degree of the exponent
     * - The natural logarithm of r is calculated via Taylor series for log(1 + x), where x = r - 1
     * - The natural logarithm of the input is calculated by summing up the intermediate results above
     * - For example: log(250) = log(e^4 * e^1 * e^0.5 * 1.021692859) = 4 + 1 + 0.5 + log(1 + 0.021692859)
     */
    function optimalLog(uint256 x) internal pure returns (uint256) {
        uint256 res = 0;

        uint256 y;
        uint256 z;
        uint256 w;

        if (x >= 0xd3094c70f034de4b96ff7d5b6f99fcd8) {
            res += 0x40000000000000000000000000000000;
            x = (x * FIXED_1) / 0xd3094c70f034de4b96ff7d5b6f99fcd8;
        }
        // add 1 / 2^1
        if (x >= 0xa45af1e1f40c333b3de1db4dd55f29a7) {
            res += 0x20000000000000000000000000000000;
            x = (x * FIXED_1) / 0xa45af1e1f40c333b3de1db4dd55f29a7;
        }
        // add 1 / 2^2
        if (x >= 0x910b022db7ae67ce76b441c27035c6a1) {
            res += 0x10000000000000000000000000000000;
            x = (x * FIXED_1) / 0x910b022db7ae67ce76b441c27035c6a1;
        }
        // add 1 / 2^3
        if (x >= 0x88415abbe9a76bead8d00cf112e4d4a8) {
            res += 0x08000000000000000000000000000000;
            x = (x * FIXED_1) / 0x88415abbe9a76bead8d00cf112e4d4a8;
        }
        // add 1 / 2^4
        if (x >= 0x84102b00893f64c705e841d5d4064bd3) {
            res += 0x04000000000000000000000000000000;
            x = (x * FIXED_1) / 0x84102b00893f64c705e841d5d4064bd3;
        }
        // add 1 / 2^5
        if (x >= 0x8204055aaef1c8bd5c3259f4822735a2) {
            res += 0x02000000000000000000000000000000;
            x = (x * FIXED_1) / 0x8204055aaef1c8bd5c3259f4822735a2;
        }
        // add 1 / 2^6
        if (x >= 0x810100ab00222d861931c15e39b44e99) {
            res += 0x01000000000000000000000000000000;
            x = (x * FIXED_1) / 0x810100ab00222d861931c15e39b44e99;
        }
        // add 1 / 2^7
        if (x >= 0x808040155aabbbe9451521693554f733) {
            res += 0x00800000000000000000000000000000;
            x = (x * FIXED_1) / 0x808040155aabbbe9451521693554f733;
        }
        // add 1 / 2^8

        z = y = x - FIXED_1;
        w = (y * y) / FIXED_1;
        res += (z * (0x100000000000000000000000000000000 - y)) / 0x100000000000000000000000000000000;
        z = (z * w) / FIXED_1;
        // add y^01 / 01 - y^02 / 02
        res += (z * (0x0aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa - y)) / 0x200000000000000000000000000000000;
        z = (z * w) / FIXED_1;
        // add y^03 / 03 - y^04 / 04
        res += (z * (0x099999999999999999999999999999999 - y)) / 0x300000000000000000000000000000000;
        z = (z * w) / FIXED_1;
        // add y^05 / 05 - y^06 / 06
        res += (z * (0x092492492492492492492492492492492 - y)) / 0x400000000000000000000000000000000;
        z = (z * w) / FIXED_1;
        // add y^07 / 07 - y^08 / 08
        res += (z * (0x08e38e38e38e38e38e38e38e38e38e38e - y)) / 0x500000000000000000000000000000000;
        z = (z * w) / FIXED_1;
        // add y^09 / 09 - y^10 / 10
        res += (z * (0x08ba2e8ba2e8ba2e8ba2e8ba2e8ba2e8b - y)) / 0x600000000000000000000000000000000;
        z = (z * w) / FIXED_1;
        // add y^11 / 11 - y^12 / 12
        res += (z * (0x089d89d89d89d89d89d89d89d89d89d89 - y)) / 0x700000000000000000000000000000000;
        z = (z * w) / FIXED_1;
        // add y^13 / 13 - y^14 / 14
        res += (z * (0x088888888888888888888888888888888 - y)) / 0x800000000000000000000000000000000;
        // add y^15 / 15 - y^16 / 16

        return res;
    }

    /**
     * @dev computes e ^ (x / FIXED_1) * FIXED_1
     * input range: 0 <= x <= OPT_EXP_MAX_VAL - 1
     * auto-generated via 'PrintFunctionOptimalExp.py'
     * Detailed description:
     * - Rewrite the input as a sum of binary exponents and a single residual r, as small as possible
     * - The exponentiation of each binary exponent is given (pre-calculated)
     * - The exponentiation of r is calculated via Taylor series for e^x, where x = r
     * - The exponentiation of the input is calculated by multiplying the intermediate results above
     * - For example: e^5.521692859 = e^(4 + 1 + 0.5 + 0.021692859) = e^4 * e^1 * e^0.5 * e^0.021692859
     */
    function optimalExp(uint256 x) internal pure returns (uint256) {
        uint256 res = 0;

        uint256 y;
        uint256 z;

        z = y = x % 0x10000000000000000000000000000000;
        // get the input modulo 2^(-3)
        z = (z * y) / FIXED_1;
        res += z * 0x10e1b3be415a0000;
        // add y^02 * (20! / 02!)
        z = (z * y) / FIXED_1;
        res += z * 0x05a0913f6b1e0000;
        // add y^03 * (20! / 03!)
        z = (z * y) / FIXED_1;
        res += z * 0x0168244fdac78000;
        // add y^04 * (20! / 04!)
        z = (z * y) / FIXED_1;
        res += z * 0x004807432bc18000;
        // add y^05 * (20! / 05!)
        z = (z * y) / FIXED_1;
        res += z * 0x000c0135dca04000;
        // add y^06 * (20! / 06!)
        z = (z * y) / FIXED_1;
        res += z * 0x0001b707b1cdc000;
        // add y^07 * (20! / 07!)
        z = (z * y) / FIXED_1;
        res += z * 0x000036e0f639b800;
        // add y^08 * (20! / 08!)
        z = (z * y) / FIXED_1;
        res += z * 0x00000618fee9f800;
        // add y^09 * (20! / 09!)
        z = (z * y) / FIXED_1;
        res += z * 0x0000009c197dcc00;
        // add y^10 * (20! / 10!)
        z = (z * y) / FIXED_1;
        res += z * 0x0000000e30dce400;
        // add y^11 * (20! / 11!)
        z = (z * y) / FIXED_1;
        res += z * 0x000000012ebd1300;
        // add y^12 * (20! / 12!)
        z = (z * y) / FIXED_1;
        res += z * 0x0000000017499f00;
        // add y^13 * (20! / 13!)
        z = (z * y) / FIXED_1;
        res += z * 0x0000000001a9d480;
        // add y^14 * (20! / 14!)
        z = (z * y) / FIXED_1;
        res += z * 0x00000000001c6380;
        // add y^15 * (20! / 15!)
        z = (z * y) / FIXED_1;
        res += z * 0x000000000001c638;
        // add y^16 * (20! / 16!)
        z = (z * y) / FIXED_1;
        res += z * 0x0000000000001ab8;
        // add y^17 * (20! / 17!)
        z = (z * y) / FIXED_1;
        res += z * 0x000000000000017c;
        // add y^18 * (20! / 18!)
        z = (z * y) / FIXED_1;
        res += z * 0x0000000000000014;
        // add y^19 * (20! / 19!)
        z = (z * y) / FIXED_1;
        res += z * 0x0000000000000001;
        // add y^20 * (20! / 20!)
        res = res / 0x21c3677c82b40000 + y + FIXED_1;
        // divide by 20! and then add y^1 / 1! + y^0 / 0!

        if ((x & 0x010000000000000000000000000000000) != 0)
            res = (res * 0x1c3d6a24ed82218787d624d3e5eba95f9) / 0x18ebef9eac820ae8682b9793ac6d1e776;
        // multiply by e^2^(-3)
        if ((x & 0x020000000000000000000000000000000) != 0)
            res = (res * 0x18ebef9eac820ae8682b9793ac6d1e778) / 0x1368b2fc6f9609fe7aceb46aa619baed4;
        // multiply by e^2^(-2)
        if ((x & 0x040000000000000000000000000000000) != 0)
            res = (res * 0x1368b2fc6f9609fe7aceb46aa619baed5) / 0x0bc5ab1b16779be3575bd8f0520a9f21f;
        // multiply by e^2^(-1)
        if ((x & 0x080000000000000000000000000000000) != 0)
            res = (res * 0x0bc5ab1b16779be3575bd8f0520a9f21e) / 0x0454aaa8efe072e7f6ddbab84b40a55c9;
        // multiply by e^2^(+0)
        if ((x & 0x100000000000000000000000000000000) != 0)
            res = (res * 0x0454aaa8efe072e7f6ddbab84b40a55c5) / 0x00960aadc109e7a3bf4578099615711ea;
        // multiply by e^2^(+1)
        if ((x & 0x200000000000000000000000000000000) != 0)
            res = (res * 0x00960aadc109e7a3bf4578099615711d7) / 0x0002bf84208204f5977f9a8cf01fdce3d;
        // multiply by e^2^(+2)
        if ((x & 0x400000000000000000000000000000000) != 0)
            res = (res * 0x0002bf84208204f5977f9a8cf01fdc307) / 0x0000003c6ab775dd0b95b4cbee7e65d11;
        // multiply by e^2^(+3)

        return res;
    }

    function setDexConfigor(address _dexConfigor) external onlyDexConfigor {
        dexConfigor = _dexConfigor;
    }

    function setDexSwapFee(uint8 _dexId, uint32 _swapFee) external onlyDexConfigor {
        _setDexSwapFee(_dexId, _swapFee);
    }

    function _setDexSwapFee(uint8 _dexId, uint32 _swapFee) internal {
        require(_swapFee < 10000, 'FBP: Invalid swap fee');
        dexSwapFee[_dexId] = _swapFee;
        dexSupported[_dexId] = true;
        emit LogDexSwapFee(_dexId, _swapFee, true);
    }

    function disableDex(uint8 _dexId) external onlyDexConfigor {
        dexSupported[_dexId] = false;
        emit LogDexSwapFee(_dexId, dexSwapFee[_dexId], false);
    }

    function getFactoryReserveAndWeights(address factory, address pair, address tokenA, uint8 dexId) public override view returns (
        address tokenB,
        uint reserveA,
        uint reserveB,
        uint32 tokenWeightA,
        uint32 tokenWeightB,
        uint32 swapFee
    ) {
        (uint reserve0, uint reserve1,) = IFireBirdPair(pair).getReserves();
        uint32 tokenWeight0;
        uint32 tokenWeight1;
        (tokenWeight0, tokenWeight1, swapFee) = getFactoryWeightsAndSwapFee(factory, pair, dexId);

        if (tokenA == IFireBirdPair(pair).token0()) {
            (tokenB, reserveA, reserveB, tokenWeightA, tokenWeightB) = (IFireBirdPair(pair).token1(), reserve0, reserve1, tokenWeight0, tokenWeight1);
        } else if (tokenA == IFireBirdPair(pair).token1()) {
            (tokenB, reserveA, reserveB, tokenWeightA, tokenWeightB) = (IFireBirdPair(pair).token0(), reserve1, reserve0, tokenWeight1, tokenWeight0);
        } else {
            revert("FireBirdFormula: Invalid tokenA");
        }
    }
    /**
         * @dev given an input amount of an asset and pair reserves, returns the maximum output amount of the other asset,
         *
         * Formula:
         * return = reserveOut * (1 - (reserveIn * 10000 / (reserveIn * 10000 + amountIn * (10000 - swapFee))) ^ (tokenWeightIn / tokenWeightOut))
         *
         * @param amountIn                  source reserve amount
         * @param reserveIn    source reserve balance
         * @param reserveOut    target reserve balance
         * @param tokenWeightIn     source reserve weight, represented in ppm (2-98)
         * @param tokenWeightOut     target reserve weight, represented in ppm (2-98)
         * @param swapFee                  swap fee of the conversion
         *
         * @return amountOut
         */
    function getAmountOut(
        uint amountIn,
        uint reserveIn, uint reserveOut,
        uint32 tokenWeightIn, uint32 tokenWeightOut,
        uint32 swapFee
    ) public override view returns (uint amountOut) {
        // validate input
        require(amountIn > 0, 'FireBirdFormula: INSUFFICIENT_INPUT_AMOUNT');
        require(reserveIn > 0 && reserveOut > 0, "FireBirdFormula: INSUFFICIENT_LIQUIDITY");
        uint amountInWithFee = amountIn.mul(10000 - swapFee);
        // special case for equal weights
        if (tokenWeightIn == tokenWeightOut) {
            return reserveOut.mul(amountInWithFee) / (reserveIn.mul(10000).add(amountInWithFee));
        }

        uint256 result;
        uint8 precision;
        uint256 baseN = reserveIn.mul(10000).add(amountInWithFee);
        (result, precision) = power(baseN, reserveIn.mul(10000), tokenWeightIn, tokenWeightOut);

        uint256 temp1 = reserveOut.mul(result);
        uint256 temp2 = reserveOut << precision;
        return (temp1 - temp2) / result;
    }

    /**
         * @dev given an output amount of an asset and pair reserves, returns a required input amount of the other asset
         *
         * Formula:
         * return = reserveIn * ( (reserveOut / (reserveOut - amountOut)) ^ (tokenWeightOut / tokenWeightIn) - 1) * (10000/ (10000 - swapFee)
         *
         * @param amountOut     target reserve amount
         * @param reserveIn    source reserve balance
         * @param reserveOut    target reserve balance
         * @param tokenWeightIn     source reserve weight, represented in ppm (2-98)
         * @param tokenWeightOut     target reserve weight, represented in ppm (2-98)
         * @param swapFee                  swap fee of the conversion
         *
         * @return amountIn
         */
    function getAmountIn(
        uint amountOut,
        uint reserveIn, uint reserveOut,
        uint32 tokenWeightIn, uint32 tokenWeightOut,
        uint32 swapFee
    ) public override view returns (uint amountIn) {
        // validate input
        require(amountOut > 0, 'FireBirdFormula: INSUFFICIENT_OUTPUT_AMOUNT');
        require(reserveIn > 0 && reserveOut > 0, "FireBirdFormula: INSUFFICIENT_LIQUIDITY");
        // special case for equal weights
        if (tokenWeightIn == tokenWeightOut) {
            uint numerator = reserveIn.mul(amountOut).mul(10000);
            uint denominator = reserveOut.sub(amountOut).mul(10000 - swapFee);
            return (numerator / denominator).add(1);
        }

        uint256 result;
        uint8 precision;
        uint256 baseD = reserveOut.sub(amountOut);
        (result, precision) = power(reserveOut, baseD, tokenWeightOut, tokenWeightIn);
        uint256 baseReserveIn = reserveIn.mul(10000);
        uint256 temp1 = baseReserveIn.mul(result);
        uint256 temp2 = baseReserveIn << precision;
        return (((temp1 - temp2) >> precision) / (10000 - swapFee)).add(1);
    }

    function getFactoryAmountsOut(address factory, address tokenIn, address tokenOut, uint amountIn, address[] memory path, uint8[] memory dexIds) external override view returns (uint[] memory amounts) {
        require(path.length > 0, 'FireBirdFormula: INVALID_PATH');
        amounts = new uint[](path.length + 1);
        amounts[0] = amountIn;
        address currentTokenIn = tokenIn;
        for (uint i = 0; i < path.length; i++) {
            (address currentTokenOut, uint reserveIn, uint reserveOut, uint32 tokenWeightIn, uint32 tokenWeightOut, uint32 swapFee) = getFactoryReserveAndWeights(factory, path[i], currentTokenIn, dexIds[i]);
            amounts[i + 1] = getAmountOut(amounts[i], reserveIn, reserveOut, tokenWeightIn, tokenWeightOut, swapFee);
            currentTokenIn = currentTokenOut;
        }
        require(currentTokenIn == tokenOut, 'FireBirdFormula: INVALID_TOKEN_OUT_PATH');
    }

    function getFactoryAmountsIn(address factory, address tokenIn, address tokenOut, uint amountOut, address[] memory path, uint8[] memory dexIds) external override view returns (uint[] memory amounts) {
        require(path.length > 0, 'FireBirdFormula: INVALID_PATH');
        amounts = new uint[](path.length + 1);
        amounts[amounts.length - 1] = amountOut;
        address currentTokenIn = tokenOut;
        for (uint i = path.length; i > 0; i--) {
            (address currentTokenOut, uint reserveIn, uint reserveOut, uint32 tokenWeightIn, uint32 tokenWeightOut, uint32 swapFee) = getFactoryReserveAndWeights(factory, path[i - 1], currentTokenIn, dexIds[i - 1]);
            amounts[i - 1] = getAmountIn(amounts[i], reserveOut, reserveIn, tokenWeightOut, tokenWeightIn, swapFee);
            currentTokenIn = currentTokenOut;

        }
        require(currentTokenIn == tokenIn, 'FireBirdFormula: INVALID_TOKEN_IN_PATH');
    }

    function getFactoryWeightsAndSwapFee(address factory, address pair, uint8 dexId) public override view returns (uint32 tokenWeight0, uint32 tokenWeight1, uint32 swapFee) {
        if (dexId == 0) {
            return IFireBirdFactory(factory).getWeightsAndSwapFee(pair);
        } else {
            if (dexSupported[dexId]) {
                return (50, 50, dexSwapFee[dexId]);
            } else {
                revert("FBF: Dex not supported");
            }
        }
    }

    // Ensure constant value reserve0^(tokenWeight0/50) * reserve1^((100 - tokenWeight0)/50) <= balance0Adjusted^(tokenWeight0/50) * balance1Adjusted^((100 - tokenWeight0)/50)
    //  1 <= (balance0Adjusted / reserve0 )^(tokenWeight0/50) * (balance1Adjusted/reserve1)^((100 - tokenWeight0)/50)
    //  (reserve0 / balance0Adjusted) ^ (tokenWeight0/50) <=  (balance1Adjusted / reserve1) ^ ((100 - tokenWeight0)/50)
    function ensureConstantValue(uint reserve0, uint reserve1, uint balance0Adjusted, uint balance1Adjusted, uint32 tokenWeight0) external override view returns (bool) {
        if (tokenWeight0 == 50) {
            return balance0Adjusted.mul(balance1Adjusted) >= reserve0.mul(reserve1);
        }
        if (balance0Adjusted >= reserve0 && balance1Adjusted >= reserve1) {
            return true;
        }
        if (balance0Adjusted <= reserve0 && balance1Adjusted <= reserve1) {
            return false;
        }
        uint32 w0 = tokenWeight0;
        uint32 w1 = 100 - w0;

        uint r0;
        uint p0;
        uint r1;
        uint p1;
        if (balance0Adjusted >= reserve0) {
            (r0, p0) = power(reserve1, balance1Adjusted, w1, 50);
            (r1, p1) = power(balance0Adjusted, reserve0, w0, 50);
        } else {
            (r0, p0) = power(reserve0, balance0Adjusted, w0, 50);
            (r1, p1) = power(balance1Adjusted, reserve1, w1, 50);
        }
        uint minP = p0 < p1 ? p0 : p1;
        p0 = p0 - minP;
        p1 = p1 - minP;
        return (r0 >> p0) <= (r1 >> p1);
    }

    function sortTokens(address tokenA, address tokenB) public pure override returns (address token0, address token1) {
        require(tokenA != tokenB, 'FireBirdFormula: IDENTICAL_ADDRESSES');
        (token0, token1) = tokenA < tokenB ? (tokenA, tokenB) : (tokenB, tokenA);
        require(token0 != address(0), 'FireBirdFormula: ZERO_ADDRESS');
    }

    function getReserves(address pair, address tokenA, address tokenB) external view override returns (uint reserveA, uint reserveB) {
        (address token0, address token1) = sortTokens(tokenA, tokenB);
        (uint reserve0, uint reserve1,) = IFireBirdPair(pair).getReserves();
        require(token0 == IFireBirdPair(pair).token0() && token1 == IFireBirdPair(pair).token1(), 'FireBirdFormula: Invalid token');
        (reserveA, reserveB) = tokenA == token0 ? (reserve0, reserve1) : (reserve1, reserve0);
    }

    function getOtherToken(address pair, address tokenA) external view override returns (address tokenB) {
        address token0 = IFireBirdPair(pair).token0();
        address token1 = IFireBirdPair(pair).token1();
        require(token0 == tokenA || token1 == tokenA, 'FireBirdFormula: Invalid tokenA');
        tokenB = token0 == tokenA ? token1 : token0;
    }
    // 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) external pure override returns (uint amountB) {
        require(amountA > 0, 'FireBirdFormula: INSUFFICIENT_AMOUNT');
        require(reserveA > 0 && reserveB > 0, 'FireBirdFormula: INSUFFICIENT_LIQUIDITY');
        amountB = amountA.mul(reserveB) / reserveA;
    }
    function mintLiquidityFee(
        uint totalLiquidity,
        uint112 reserve0,
        uint112  reserve1,
        uint32 tokenWeight0,
        uint32 tokenWeight1,
        uint112  collectedFee0,
        uint112 collectedFee1) external view override returns (uint amount) {
        if (collectedFee0 > 0) {
            (uint r0, uint p0) = power(uint(collectedFee0).add(reserve0), reserve0, tokenWeight0, 100);
            amount = amount.add(totalLiquidity.mul(r0) >> p0).sub(totalLiquidity);
        }
        if (collectedFee1 > 0) {
            (uint r1, uint p1) = power(uint(collectedFee1).add(reserve1), reserve1, tokenWeight1, 100);
            amount = amount.add(totalLiquidity.mul(r1) >> p1).sub(totalLiquidity);
        }
    }


}