// hevm: flattened sources of /nix/store/8xb41r4qd0cjb63wcrxf1qmfg88p0961-dss-6fd7de0/src/dai.sol
pragma solidity =0.5.12;

////// /nix/store/8xb41r4qd0cjb63wcrxf1qmfg88p0961-dss-6fd7de0/src/lib.sol
// 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 0.5.12; */

contract LibNote {
    event LogNote(
        bytes4   indexed  sig,
        address  indexed  usr,
        bytes32  indexed  arg1,
        bytes32  indexed  arg2,
        bytes             data
    ) anonymous;

    modifier note {
        _;
        assembly {
            // log an 'anonymous' event with a constant 6 words of calldata
            // and four indexed topics: selector, caller, arg1 and arg2
            let mark := msize                         // end of memory ensures zero
            mstore(0x40, add(mark, 288))              // update free memory pointer
            mstore(mark, 0x20)                        // bytes type data offset
            mstore(add(mark, 0x20), 224)              // bytes size (padded)
            calldatacopy(add(mark, 0x40), 0, 224)     // bytes payload
            log4(mark, 288,                           // calldata
                 shl(224, shr(224, calldataload(0))), // msg.sig
                 caller,                              // msg.sender
                 calldataload(4),                     // arg1
                 calldataload(36)                     // arg2
                )
        }
    }
}

////// /nix/store/8xb41r4qd0cjb63wcrxf1qmfg88p0961-dss-6fd7de0/src/dai.sol
// Copyright (C) 2017, 2018, 2019 dbrock, rain, mrchico

// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero 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 Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <https://www.gnu.org/licenses/>.

/* pragma solidity 0.5.12; */

/* import "./lib.sol"; */

contract Dai is LibNote {
    // --- Auth ---
    mapping (address => uint) public wards;
    function rely(address guy) external note auth { wards[guy] = 1; }
    function deny(address guy) external note auth { wards[guy] = 0; }
    modifier auth {
        require(wards[msg.sender] == 1, "Dai/not-authorized");
        _;
    }

    // --- ERC20 Data ---
    string  public constant name     = "Dai Stablecoin";
    string  public constant symbol   = "DAI";
    string  public constant version  = "1";
    uint8   public constant decimals = 18;
    uint256 public totalSupply;

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

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

    // --- Math ---
    function add(uint x, uint y) internal pure returns (uint z) {
        require((z = x + y) >= x);
    }
    function sub(uint x, uint y) internal pure returns (uint z) {
        require((z = x - y) <= x);
    }

    // --- EIP712 niceties ---
    bytes32 public DOMAIN_SEPARATOR;
    // bytes32 public constant PERMIT_TYPEHASH = keccak256("Permit(address holder,address spender,uint256 nonce,uint256 expiry,bool allowed)");
    bytes32 public constant PERMIT_TYPEHASH = 0xea2aa0a1be11a07ed86d755c93467f4f82362b452371d1ba94d1715123511acb;

    constructor(uint256 chainId_) public {
        wards[msg.sender] = 1;
        DOMAIN_SEPARATOR = keccak256(abi.encode(
            keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"),
            keccak256(bytes(name)),
            keccak256(bytes(version)),
            chainId_,
            address(this)
        ));
    }

    // --- Token ---
    function transfer(address dst, uint wad) external returns (bool) {
        return transferFrom(msg.sender, dst, wad);
    }
    function transferFrom(address src, address dst, uint wad)
        public returns (bool)
    {
        require(balanceOf[src] >= wad, "Dai/insufficient-balance");
        if (src != msg.sender && allowance[src][msg.sender] != uint(-1)) {
            require(allowance[src][msg.sender] >= wad, "Dai/insufficient-allowance");
            allowance[src][msg.sender] = sub(allowance[src][msg.sender], wad);
        }
        balanceOf[src] = sub(balanceOf[src], wad);
        balanceOf[dst] = add(balanceOf[dst], wad);
        emit Transfer(src, dst, wad);
        return true;
    }
    function mint(address usr, uint wad) external auth {
        balanceOf[usr] = add(balanceOf[usr], wad);
        totalSupply    = add(totalSupply, wad);
        emit Transfer(address(0), usr, wad);
    }
    function burn(address usr, uint wad) external {
        require(balanceOf[usr] >= wad, "Dai/insufficient-balance");
        if (usr != msg.sender && allowance[usr][msg.sender] != uint(-1)) {
            require(allowance[usr][msg.sender] >= wad, "Dai/insufficient-allowance");
            allowance[usr][msg.sender] = sub(allowance[usr][msg.sender], wad);
        }
        balanceOf[usr] = sub(balanceOf[usr], wad);
        totalSupply    = sub(totalSupply, wad);
        emit Transfer(usr, address(0), wad);
    }
    function approve(address usr, uint wad) external returns (bool) {
        allowance[msg.sender][usr] = wad;
        emit Approval(msg.sender, usr, wad);
        return true;
    }

    // --- Alias ---
    function push(address usr, uint wad) external {
        transferFrom(msg.sender, usr, wad);
    }
    function pull(address usr, uint wad) external {
        transferFrom(usr, msg.sender, wad);
    }
    function move(address src, address dst, uint wad) external {
        transferFrom(src, dst, wad);
    }

    // --- Approve by signature ---
    function permit(address holder, address spender, uint256 nonce, uint256 expiry,
                    bool allowed, uint8 v, bytes32 r, bytes32 s) external
    {
        bytes32 digest =
            keccak256(abi.encodePacked(
                "\x19\x01",
                DOMAIN_SEPARATOR,
                keccak256(abi.encode(PERMIT_TYPEHASH,
                                     holder,
                                     spender,
                                     nonce,
                                     expiry,
                                     allowed))
        ));

        require(holder != address(0), "Dai/invalid-address-0");
        require(holder == ecrecover(digest, v, r, s), "Dai/invalid-permit");
        require(expiry == 0 || now <= expiry, "Dai/permit-expired");
        require(nonce == nonces[holder]++, "Dai/invalid-nonce");
        uint wad = allowed ? uint(-1) : 0;
        allowance[holder][spender] = wad;
        emit Approval(holder, spender, wad);
    }
}

// SPDX-License-Identifier: GPL-3.0-or-later
pragma solidity >=0.6.0;
// 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::safeApprove: approve failed'
        );
    }
    function safeTransfer(
        address token,
        address to,
        uint256 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::safeTransfer: transfer failed'
        );
    }
    function safeTransferFrom(
        address token,
        address from,
        address to,
        uint256 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::transferFrom: transferFrom failed'
        );
    }
    function safeTransferETH(address to, uint256 value) internal {
        (bool success, ) = to.call{value: value}(new bytes(0));
        require(success, 'TransferHelper::safeTransferETH: ETH transfer failed');
    }
}
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;
}
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;
}
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);
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
import "./IERC20.sol";
interface IFewERC20 is IERC20 {
    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;
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
interface IFewFactory {
    event WrappedTokenCreated(address indexed originalToken, address wrappedToken, uint);
    function getWrappedToken(address originalToken) external view returns (address wrappedToken);
    function allWrappedTokens(uint) external view returns (address wrappedToken);
    function parameter() external view returns (address);
    function allWrappedTokensLength() external view returns (uint);
    function paused() external view returns (bool);
    function createToken(address originalToken) external returns (address wrappedToken);
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
import "../interfaces/IFewERC20.sol";
interface IFewWrappedToken is IFewERC20 {
    event Mint(address indexed minter, uint256 amount, address indexed to);
    event Burn(address indexed burner, uint256 amount, address indexed to);
    event Wrap(address indexed sender, uint256 amount, address indexed to);
    event Unwrap(address indexed sender, uint256 amount, address indexed to);
    function factory() external view returns (address);
    function token() external view returns (address);
    function burn(uint256 amount) external;
    function burnFrom(address account, uint256 amount) external;
    function mint(address account, uint256 amount) external;
    function wrap(uint256 amount) external returns (uint256);
    function wrapTo(uint256 amount, address to) external returns (uint256);
    function unwrap(uint256 amount) external returns (uint256);
    function unwrapTo(uint256 amount, address to) external returns (uint256);
}
pragma solidity >=0.6.2;
import './IUniswapV2Router01.sol';
interface ISwapV2Router is IUniswapV2Router01 {
    function fewFactory() external pure returns (address);
    function fwWETH() external pure returns (address);
}
pragma solidity >=0.6.2;
import './IUniswapV2Router01Base.sol';
interface IUniswapV2Router01 is IUniswapV2Router01Base {
    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);
}
pragma solidity >=0.6.2;
interface IUniswapV2Router01Base {
    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);
}
pragma solidity >=0.5.0;
interface IWETH {
    function deposit() external payable;
    function transfer(address to, uint value) external returns (bool);
    function withdraw(uint) external;
}
pragma solidity =0.6.6;
// 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');
    }
}
pragma solidity >=0.5.0;
import '@uniswap/v2-core/contracts/interfaces/IUniswapV2Pair.sol';
import "./SafeMath.sol";
library SwapV2Library {
    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, 'SwapV2Library: IDENTICAL_ADDRESSES');
        (token0, token1) = tokenA < tokenB ? (tokenA, tokenB) : (tokenB, tokenA);
        require(token0 != address(0), 'SwapV2Library: 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'a7ae6a5ec37f0c21bbdac560794258c4089b8ae3ffa6e3909b53c6091764a676' // 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, 'SwapV2Library: INSUFFICIENT_AMOUNT');
        require(reserveA > 0 && reserveB > 0, 'SwapV2Library: 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, 'SwapV2Library: INSUFFICIENT_INPUT_AMOUNT');
        require(reserveIn > 0 && reserveOut > 0, 'SwapV2Library: 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, 'SwapV2Library: INSUFFICIENT_OUTPUT_AMOUNT');
        require(reserveIn > 0 && reserveOut > 0, 'SwapV2Library: 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, 'SwapV2Library: 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, 'SwapV2Library: 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);
        }
    }
}
pragma solidity =0.6.6;
import '@uniswap/v2-core/contracts/interfaces/IUniswapV2Factory.sol';
import '@uniswap/lib/contracts/libraries/TransferHelper.sol';
import './interfaces/ISwapV2Router.sol';
import './interfaces/IFewFactory.sol';
import './interfaces/IFewWrappedToken.sol';
import './libraries/SwapV2Library.sol';
import './libraries/SafeMath.sol';
import './interfaces/IERC20.sol';
import './interfaces/IWETH.sol';
contract SwapV2Router is ISwapV2Router {
    using SafeMath for uint;
    address public immutable override factory;
    address public immutable override WETH;
    address public immutable override fewFactory;
    address public immutable override fwWETH;
    modifier ensure(uint deadline) {
        require(deadline >= block.timestamp, 'SwapV2Router: EXPIRED');
        _;
    }
    constructor(address _factory, address _WETH, address _fewFactory, address _fwWETH) public {
        factory = _factory;
        WETH = _WETH;
        fewFactory = _fewFactory;
        fwWETH = _fwWETH;
    }
    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) = SwapV2Library.getReserves(factory, tokenA, tokenB);
        if (reserveA == 0 && reserveB == 0) {
            (amountA, amountB) = (amountADesired, amountBDesired);
        } else {
            uint amountBOptimal = SwapV2Library.quote(amountADesired, reserveA, reserveB);
            if (amountBOptimal <= amountBDesired) {
                require(amountBOptimal >= amountBMin, 'SwapV2Router: INSUFFICIENT_B_AMOUNT');
                (amountA, amountB) = (amountADesired, amountBOptimal);
            } else {
                uint amountAOptimal = SwapV2Library.quote(amountBDesired, reserveB, reserveA);
                assert(amountAOptimal <= amountADesired);
                require(amountAOptimal >= amountAMin, 'SwapV2Router: 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) {
        // create the wrapped token if it doesn't exist yet
        if (IFewFactory(fewFactory).getWrappedToken(tokenA) == address(0)) {
            IFewFactory(fewFactory).createToken(tokenA);
        }
        if (IFewFactory(fewFactory).getWrappedToken(tokenB) == address(0)) {
            IFewFactory(fewFactory).createToken(tokenB);
        }
        address wrappedTokenA = IFewFactory(fewFactory).getWrappedToken(tokenA);
        address wrappedTokenB = IFewFactory(fewFactory).getWrappedToken(tokenB);
        (amountA, amountB) = _addLiquidity(wrappedTokenA, wrappedTokenB, amountADesired, amountBDesired, amountAMin, amountBMin);
        address pair = SwapV2Library.pairFor(factory, wrappedTokenA, wrappedTokenB);
        TransferHelper.safeTransferFrom(tokenA, msg.sender, address(this), amountA);
        TransferHelper.safeTransferFrom(tokenB, msg.sender, address(this), amountB);
        TransferHelper.safeApprove(tokenA, wrappedTokenA, amountA);
        TransferHelper.safeApprove(tokenB, wrappedTokenB, amountB);
        IFewWrappedToken(wrappedTokenA).wrapTo(amountA, pair);
        IFewWrappedToken(wrappedTokenB).wrapTo(amountB, pair);
        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) {
        // create the wrapped token if it doesn't exist yet
        if (IFewFactory(fewFactory).getWrappedToken(token) == address(0)) {
            IFewFactory(fewFactory).createToken(token);
        }
        address wrappedToken = IFewFactory(fewFactory).getWrappedToken(token);
        (amountToken, amountETH) = _addLiquidity(
            wrappedToken,
            fwWETH,
            amountTokenDesired,
            msg.value,
            amountTokenMin,
            amountETHMin
        );
        address pair = SwapV2Library.pairFor(factory, wrappedToken, fwWETH);
        TransferHelper.safeTransferFrom(token, msg.sender, address(this), amountToken);
        IWETH(WETH).deposit{value: amountETH}();
        TransferHelper.safeApprove(token, wrappedToken, amountToken);
        TransferHelper.safeApprove(WETH, fwWETH, amountETH);
        IFewWrappedToken(wrappedToken).wrapTo(amountToken, pair);
        IFewWrappedToken(fwWETH).wrapTo(amountETH, pair);
        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 = SwapV2Library.pairFor(factory, tokenA, tokenB);
        IUniswapV2Pair(pair).transferFrom(msg.sender, pair, liquidity); // send liquidity to pair
        (uint amount0, uint amount1) = IUniswapV2Pair(pair).burn(address(this));
        (address token0,) = SwapV2Library.sortTokens(tokenA, tokenB);
        (amountA, amountB) = tokenA == token0 ? (amount0, amount1) : (amount1, amount0);
        require(amountA >= amountAMin, 'SwapV2Router: INSUFFICIENT_A_AMOUNT');
        require(amountB >= amountBMin, 'SwapV2Router: INSUFFICIENT_B_AMOUNT');
        IFewWrappedToken(tokenA).unwrapTo(amountA, to);
        IFewWrappedToken(tokenB).unwrapTo(amountB, to);
    }
    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,
            fwWETH,
            liquidity,
            amountTokenMin,
            amountETHMin,
            address(this),
            deadline
        );
        TransferHelper.safeTransfer(IFewWrappedToken(token).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 = SwapV2Library.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 = SwapV2Library.pairFor(factory, token, fwWETH);
        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);
    }
    // **** 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,) = SwapV2Library.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 ? SwapV2Library.pairFor(factory, output, path[i + 2]) : _to;
            IUniswapV2Pair(SwapV2Library.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 = SwapV2Library.getAmountsOut(factory, amountIn, path);
        require(amounts[amounts.length - 1] >= amountOutMin, 'SwapV2Router: INSUFFICIENT_OUTPUT_AMOUNT');
        address srcToken = IFewWrappedToken(path[0]).token();
        TransferHelper.safeTransferFrom(srcToken, msg.sender, address(this), amounts[0]);
        TransferHelper.safeApprove(srcToken, path[0], amounts[0]);
        IFewWrappedToken(path[0]).wrapTo(amounts[0], SwapV2Library.pairFor(factory, path[0], path[1]));
        _swap(amounts, path, address(this));
        address dstWrappedToken = path[path.length - 1];
        IFewWrappedToken(dstWrappedToken).unwrapTo(amounts[amounts.length - 1], to);
    }
    function swapTokensForExactTokens(
        uint amountOut,
        uint amountInMax,
        address[] calldata path,
        address to,
        uint deadline
    ) external virtual override ensure(deadline) returns (uint[] memory amounts) {
        amounts = SwapV2Library.getAmountsIn(factory, amountOut, path);
        require(amounts[0] <= amountInMax, 'SwapV2Router: EXCESSIVE_INPUT_AMOUNT');
        address srcToken = IFewWrappedToken(path[0]).token();
        TransferHelper.safeTransferFrom(srcToken, msg.sender, address(this), amounts[0]);
        TransferHelper.safeApprove(srcToken, path[0], amounts[0]);
        IFewWrappedToken(path[0]).wrapTo(amounts[0], SwapV2Library.pairFor(factory, path[0], path[1]));
        _swap(amounts, path, address(this));
        address dstWrappedToken = path[path.length - 1];
        IFewWrappedToken(dstWrappedToken).unwrapTo(amounts[amounts.length - 1], 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] == fwWETH, 'SwapV2Router: INVALID_PATH');
        amounts = SwapV2Library.getAmountsOut(factory, msg.value, path);
        require(amounts[amounts.length - 1] >= amountOutMin, 'SwapV2Router: INSUFFICIENT_OUTPUT_AMOUNT');
        IWETH(WETH).deposit{value: amounts[0]}();
        TransferHelper.safeApprove(WETH, fwWETH, amounts[0]);
        IFewWrappedToken(fwWETH).wrapTo(amounts[0], SwapV2Library.pairFor(factory, path[0], path[1]));
        _swap(amounts, path, address(this));
        address dstWrappedToken = path[path.length - 1];
        IFewWrappedToken(dstWrappedToken).unwrapTo(amounts[amounts.length - 1], 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] == fwWETH, 'SwapV2Router: INVALID_PATH');
        amounts = SwapV2Library.getAmountsIn(factory, amountOut, path);
        require(amounts[0] <= amountInMax, 'SwapV2Router: EXCESSIVE_INPUT_AMOUNT');
        address srcToken = IFewWrappedToken(path[0]).token();
        TransferHelper.safeTransferFrom(srcToken, msg.sender, address(this), amounts[0]);
        TransferHelper.safeApprove(srcToken, path[0], amounts[0]);
        IFewWrappedToken(path[0]).wrapTo(amounts[0], SwapV2Library.pairFor(factory, path[0], path[1]));
        _swap(amounts, path, address(this));
        IFewWrappedToken(fwWETH).unwrap(amounts[amounts.length - 1]);
        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] == fwWETH, 'SwapV2Router: INVALID_PATH');
        amounts = SwapV2Library.getAmountsOut(factory, amountIn, path);
        require(amounts[amounts.length - 1] >= amountOutMin, 'SwapV2Router: INSUFFICIENT_OUTPUT_AMOUNT');
        address srcToken = IFewWrappedToken(path[0]).token();
        TransferHelper.safeTransferFrom(srcToken, msg.sender, address(this), amounts[0]);
        TransferHelper.safeApprove(srcToken, path[0], amounts[0]);
        IFewWrappedToken(path[0]).wrapTo(amounts[0], SwapV2Library.pairFor(factory, path[0], path[1]));
        _swap(amounts, path, address(this));
        IFewWrappedToken(fwWETH).unwrapTo(amounts[amounts.length - 1], 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] == fwWETH, 'SwapV2Router: INVALID_PATH');
        amounts = SwapV2Library.getAmountsIn(factory, amountOut, path);
        require(amounts[0] <= msg.value, 'SwapV2Router: EXCESSIVE_INPUT_AMOUNT');
        IWETH(WETH).deposit{value: amounts[0]}();
        TransferHelper.safeApprove(WETH, fwWETH, amounts[0]);
        IFewWrappedToken(fwWETH).wrapTo(amounts[0], SwapV2Library.pairFor(factory, path[0], path[1]));
        _swap(amounts, path, address(this));
        address dstWrappedToken = path[path.length - 1];
        IFewWrappedToken(dstWrappedToken).unwrapTo(amounts[amounts.length - 1], to);
        // refund dust eth, if any
        if (msg.value > amounts[0]) TransferHelper.safeTransferETH(msg.sender, msg.value - amounts[0]);
    }
    // **** LIBRARY FUNCTIONS ****
    function quote(uint amountA, uint reserveA, uint reserveB) public pure virtual override returns (uint amountB) {
        return SwapV2Library.quote(amountA, reserveA, reserveB);
    }
    function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut)
        public
        pure
        virtual
        override
        returns (uint amountOut)
    {
        return SwapV2Library.getAmountOut(amountIn, reserveIn, reserveOut);
    }
    function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut)
        public
        pure
        virtual
        override
        returns (uint amountIn)
    {
        return SwapV2Library.getAmountIn(amountOut, reserveIn, reserveOut);
    }
    function getAmountsOut(uint amountIn, address[] memory path)
        public
        view
        virtual
        override
        returns (uint[] memory amounts)
    {
        return SwapV2Library.getAmountsOut(factory, amountIn, path);
    }
    function getAmountsIn(uint amountOut, address[] memory path)
        public
        view
        virtual
        override
        returns (uint[] memory amounts)
    {
        return SwapV2Library.getAmountsIn(factory, amountOut, path);
    }
}

// SPDX-License-Identifier: GPL-3.0-or-later
pragma solidity >=0.6.0;
// 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::safeApprove: approve failed'
        );
    }
    function safeTransfer(
        address token,
        address to,
        uint256 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::safeTransfer: transfer failed'
        );
    }
    function safeTransferFrom(
        address token,
        address from,
        address to,
        uint256 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::transferFrom: transferFrom failed'
        );
    }
    function safeTransferETH(address to, uint256 value) internal {
        (bool success, ) = to.call{value: value}(new bytes(0));
        require(success, 'TransferHelper::safeTransferETH: ETH transfer failed');
    }
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
interface ICore {
    // ----------- Getters -----------
    function isBurner(address _address) external view returns (bool);
    function isMinter(address _address) external view returns (bool);
    function isGovernor(address _address) external view returns (bool);
    function isGuardian(address _address) external view returns (bool);
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity =0.6.6;
import '@uniswap/lib/contracts/libraries/TransferHelper.sol';
import './interfaces/IFewWrappedToken.sol';
import './libraries/SafeMath.sol';
import './refs/ICoreRef.sol';
import './interfaces/IFewFactory.sol';
/// @title Few Wrapped Token
contract FewWrappedToken is IFewWrappedToken {
    using SafeMath for uint;
    string public override name;
    string public override symbol;
    uint8 public override decimals;
    uint  public override totalSupply;
    mapping(address => uint) public override balanceOf;
    mapping(address => mapping(address => uint)) public override allowance;
    bytes32 public override DOMAIN_SEPARATOR;
    // keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)");
    bytes32 public override constant PERMIT_TYPEHASH = 0x6e71edae12b1b97f4d1f60370fef10105fa2faae0126114a169c64845d6126c9;
    mapping(address => uint) public override nonces;
    address public override factory;
    address public override token;
    modifier onlyMinter() {
        require(ICoreRef(factory).core().isMinter(msg.sender), "CoreRef: Caller is not a minter");
        _;
    }
    modifier onlyBurner() {
        require(ICoreRef(factory).core().isBurner(msg.sender), "CoreRef: Caller is not a burner");
        _;
    }
    modifier whenNotPaused() {
        require(!IFewFactory(factory).paused(), "CoreRef: Caller is paused");
        _;
    }
    event Mint(address indexed minter, uint256 amount, address indexed to);
    event Burn(address indexed burner, uint256 amount, address indexed to);
    event Wrap(address indexed sender, uint256 amount, address indexed to);
    event Unwrap(address indexed sender, uint256 amount, address indexed to);
    /// @notice Few wrapped token constructor
    constructor() public {
        uint chainId;
        assembly {
            chainId := chainid()
        }
        factory = msg.sender;
        token = IFewFactory(msg.sender).parameter();
        name = string(abi.encodePacked("Few Wrapped ", IERC20(token).name()));
        symbol = string(abi.encodePacked("fw", IERC20(token).symbol()));
        decimals = IERC20(token).decimals();
        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) internal {
        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 override returns (bool) {
        _approve(msg.sender, spender, value);
        return true;
    }
    function transfer(address to, uint value) external override returns (bool) {
        _transfer(msg.sender, to, value);
        return true;
    }
    function transferFrom(address from, address to, uint value) external override 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 override {
        require(deadline >= block.timestamp, 'Few: 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, 'Few: INVALID_SIGNATURE');
        _approve(owner, spender, value);
    }
    /// @notice mint Few wrapped tokens
    /// @param account the account to mint to
    /// @param amount the amount to mint
    function mint(address account, uint256 amount)
        external
        override
        onlyMinter
        whenNotPaused
    {
        _mint(account, amount);
        emit Mint(msg.sender, amount, account);
    }
    /// @notice burn Few wrapped tokens from caller
    /// @param amount the amount to burn
    function burn(uint256 amount) public override {
        _burn(msg.sender, amount);
        emit Burn(msg.sender, amount, msg.sender);
    }
    /// @notice burn Few wrapped tokens from specified account
    /// @param account the account to burn from
    /// @param amount the amount to burn
    function burnFrom(address account, uint256 amount)
        public
        override
        onlyBurner
        whenNotPaused
    {
        _burn(account, amount);
        emit Burn(msg.sender, amount, account);
    }
    /// @notice exchanges token to Few wrapped token
    /// @param amount the amount to wrap
    /// @param to wrapped token reciver address
    function wrapTo(uint256 amount, address to) public override returns (uint256) {
        require(amount > 0, "Few: can't wrap zero token");
        TransferHelper.safeTransferFrom(token, msg.sender, address(this), amount);
        _mint(to, amount);
        emit Wrap(msg.sender, amount, to);
        return amount;
    }
    function wrap(uint256 amount) external override returns (uint256) {
        return wrapTo(amount, msg.sender);
    }
    /// @notice exchange Few wrapped token to token
    /// @param amount the amount to unwrap
    /// @param to token receiver address
    function unwrapTo(uint256 amount, address to) public override returns (uint256) {
        require(amount > 0, "Few: zero amount unwrap not allowed");
        _burn(msg.sender, amount);
        TransferHelper.safeTransfer(address(token), to, amount);
        emit Unwrap(msg.sender, amount, to);
        return amount;
    }
    function unwrap(uint256 amount) external override returns (uint256) {
        return unwrapTo(amount, msg.sender);
    }
}
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);
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
import './IERC20.sol';
interface IFewERC20 is IERC20 {
    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;
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
interface IFewFactory {
    event WrappedTokenCreated(address indexed originalToken, address wrappedToken, uint);
    function getWrappedToken(address originalToken) external view returns (address wrappedToken);
    function allWrappedTokens(uint) external view returns (address wrappedToken);
    function parameter() external view returns (address);
    function allWrappedTokensLength() external view returns (uint);
    function paused() external view returns (bool);
    function createToken(address originalToken) external returns (address wrappedToken);
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
import '../interfaces/IFewERC20.sol';
interface IFewWrappedToken is IFewERC20 {
    event Mint(address indexed minter, uint256 amount, address indexed to);
    event Burn(address indexed burner, uint256 amount, address indexed to);
    event Wrap(address indexed sender, uint256 amount, address indexed to);
    event Unwrap(address indexed sender, uint256 amount, address indexed to);
    function factory() external view returns (address);
    function token() external view returns (address);
    function mint(address account, uint256 amount) external;
    function burn(uint256 amount) external;
    function burnFrom(address account, uint256 amount) external;
    function wrapTo(uint256 amount, address to) external returns (uint256);
    function wrap(uint256 amount) external returns (uint256);
    function unwrapTo(uint256 amount, address to) external returns (uint256);
    function unwrap(uint256 amount) external returns (uint256);
}
pragma solidity =0.6.6;
// 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');
    }
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
import '../core/ICore.sol';
/// @title CoreRef interface
interface ICoreRef {
    event CoreUpdate(address indexed _core);
    function setCore(address coreAddress) external;
    function pause() external;
    function unpause() external;
    function core() external view returns (ICore);
}

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);
}
pragma solidity >=0.5.0;
interface ISwapV2Callee {
    function swapV2Call(address sender, uint amount0, uint amount1, bytes calldata data) external;
}
pragma solidity >=0.5.0;
interface ISwapV2ERC20 {
    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;
}
pragma solidity >=0.5.0;
interface ISwapV2Factory {
    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;
}
pragma solidity >=0.5.0;
interface ISwapV2Pair {
    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;
}
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;
        }
    }
}
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');
    }
}
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);
    }
}
pragma solidity =0.5.16;
import './interfaces/ISwapV2ERC20.sol';
import './libraries/SafeMath.sol';
contract SwapV2ERC20 is ISwapV2ERC20 {
    using SafeMath for uint;
    string public constant name = 'Ring V2';
    string public constant symbol = 'RING-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, 'SwapV2: 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, 'SwapV2: INVALID_SIGNATURE');
        _approve(owner, spender, value);
    }
}
pragma solidity =0.5.16;
import './interfaces/ISwapV2Pair.sol';
import './SwapV2ERC20.sol';
import './libraries/Math.sol';
import './libraries/UQ112x112.sol';
import './interfaces/IERC20.sol';
import './interfaces/ISwapV2Factory.sol';
import './interfaces/ISwapV2Callee.sol';
contract SwapV2Pair is ISwapV2Pair, SwapV2ERC20 {
    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, 'SwapV2: 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))), 'SwapV2: 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, 'SwapV2: 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), 'SwapV2: 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 = ISwapV2Factory(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, 'SwapV2: 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, 'SwapV2: 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, 'SwapV2: INSUFFICIENT_OUTPUT_AMOUNT');
        (uint112 _reserve0, uint112 _reserve1,) = getReserves(); // gas savings
        require(amount0Out < _reserve0 && amount1Out < _reserve1, 'SwapV2: 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, 'SwapV2: 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) ISwapV2Callee(to).swapV2Call(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, 'SwapV2: 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), 'SwapV2: 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);
    }
}

// SPDX-License-Identifier: GPL-3.0-or-later
pragma solidity >=0.6.0;
// 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::safeApprove: approve failed'
        );
    }
    function safeTransfer(
        address token,
        address to,
        uint256 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::safeTransfer: transfer failed'
        );
    }
    function safeTransferFrom(
        address token,
        address from,
        address to,
        uint256 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::transferFrom: transferFrom failed'
        );
    }
    function safeTransferETH(address to, uint256 value) internal {
        (bool success, ) = to.call{value: value}(new bytes(0));
        require(success, 'TransferHelper::safeTransferETH: ETH transfer failed');
    }
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
interface ICore {
    // ----------- Getters -----------
    function isBurner(address _address) external view returns (bool);
    function isMinter(address _address) external view returns (bool);
    function isGovernor(address _address) external view returns (bool);
    function isGuardian(address _address) external view returns (bool);
}
// SPDX-License-Identifier: BUSL-1.1
pragma solidity =0.6.6;
import '@uniswap/lib/contracts/libraries/TransferHelper.sol';
import './interfaces/IFewWrappedToken.sol';
import './libraries/SafeMath.sol';
import './refs/ICoreRef.sol';
import './interfaces/IFewFactory.sol';
/// @title Few Wrapped Token
contract FewWrappedToken is IFewWrappedToken {
    using SafeMath for uint;
    string public override name;
    string public override symbol;
    uint8 public override decimals;
    uint  public override totalSupply;
    mapping(address => uint) public override balanceOf;
    mapping(address => mapping(address => uint)) public override allowance;
    bytes32 public override DOMAIN_SEPARATOR;
    // keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)");
    bytes32 public override constant PERMIT_TYPEHASH = 0x6e71edae12b1b97f4d1f60370fef10105fa2faae0126114a169c64845d6126c9;
    mapping(address => uint) public override nonces;
    address public override factory;
    address public override token;
    modifier onlyMinter() {
        require(ICoreRef(factory).core().isMinter(msg.sender), "CoreRef: Caller is not a minter");
        _;
    }
    modifier onlyBurner() {
        require(ICoreRef(factory).core().isBurner(msg.sender), "CoreRef: Caller is not a burner");
        _;
    }
    modifier whenNotPaused() {
        require(!IFewFactory(factory).paused(), "CoreRef: Caller is paused");
        _;
    }
    event Mint(address indexed minter, uint256 amount, address indexed to);
    event Burn(address indexed burner, uint256 amount, address indexed to);
    event Wrap(address indexed sender, uint256 amount, address indexed to);
    event Unwrap(address indexed sender, uint256 amount, address indexed to);
    /// @notice Few wrapped token constructor
    constructor() public {
        uint chainId;
        assembly {
            chainId := chainid()
        }
        factory = msg.sender;
        token = IFewFactory(msg.sender).parameter();
        name = string(abi.encodePacked("Few Wrapped ", IERC20(token).name()));
        symbol = string(abi.encodePacked("fw", IERC20(token).symbol()));
        decimals = IERC20(token).decimals();
        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) internal {
        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 override returns (bool) {
        _approve(msg.sender, spender, value);
        return true;
    }
    function transfer(address to, uint value) external override returns (bool) {
        _transfer(msg.sender, to, value);
        return true;
    }
    function transferFrom(address from, address to, uint value) external override 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 override {
        require(deadline >= block.timestamp, 'Few: 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, 'Few: INVALID_SIGNATURE');
        _approve(owner, spender, value);
    }
    /// @notice mint Few wrapped tokens
    /// @param account the account to mint to
    /// @param amount the amount to mint
    function mint(address account, uint256 amount)
        external
        override
        onlyMinter
        whenNotPaused
    {
        _mint(account, amount);
        emit Mint(msg.sender, amount, account);
    }
    /// @notice burn Few wrapped tokens from caller
    /// @param amount the amount to burn
    function burn(uint256 amount) public override {
        _burn(msg.sender, amount);
        emit Burn(msg.sender, amount, msg.sender);
    }
    /// @notice burn Few wrapped tokens from specified account
    /// @param account the account to burn from
    /// @param amount the amount to burn
    function burnFrom(address account, uint256 amount)
        public
        override
        onlyBurner
        whenNotPaused
    {
        _burn(account, amount);
        emit Burn(msg.sender, amount, account);
    }
    /// @notice exchanges token to Few wrapped token
    /// @param amount the amount to wrap
    /// @param to wrapped token reciver address
    function wrapTo(uint256 amount, address to) public override returns (uint256) {
        require(amount > 0, "Few: can't wrap zero token");
        TransferHelper.safeTransferFrom(token, msg.sender, address(this), amount);
        _mint(to, amount);
        emit Wrap(msg.sender, amount, to);
        return amount;
    }
    function wrap(uint256 amount) external override returns (uint256) {
        return wrapTo(amount, msg.sender);
    }
    /// @notice exchange Few wrapped token to token
    /// @param amount the amount to unwrap
    /// @param to token receiver address
    function unwrapTo(uint256 amount, address to) public override returns (uint256) {
        require(amount > 0, "Few: zero amount unwrap not allowed");
        _burn(msg.sender, amount);
        TransferHelper.safeTransfer(address(token), to, amount);
        emit Unwrap(msg.sender, amount, to);
        return amount;
    }
    function unwrap(uint256 amount) external override returns (uint256) {
        return unwrapTo(amount, msg.sender);
    }
}
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);
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
import './IERC20.sol';
interface IFewERC20 is IERC20 {
    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;
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
interface IFewFactory {
    event WrappedTokenCreated(address indexed originalToken, address wrappedToken, uint);
    function getWrappedToken(address originalToken) external view returns (address wrappedToken);
    function allWrappedTokens(uint) external view returns (address wrappedToken);
    function parameter() external view returns (address);
    function allWrappedTokensLength() external view returns (uint);
    function paused() external view returns (bool);
    function createToken(address originalToken) external returns (address wrappedToken);
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
import '../interfaces/IFewERC20.sol';
interface IFewWrappedToken is IFewERC20 {
    event Mint(address indexed minter, uint256 amount, address indexed to);
    event Burn(address indexed burner, uint256 amount, address indexed to);
    event Wrap(address indexed sender, uint256 amount, address indexed to);
    event Unwrap(address indexed sender, uint256 amount, address indexed to);
    function factory() external view returns (address);
    function token() external view returns (address);
    function mint(address account, uint256 amount) external;
    function burn(uint256 amount) external;
    function burnFrom(address account, uint256 amount) external;
    function wrapTo(uint256 amount, address to) external returns (uint256);
    function wrap(uint256 amount) external returns (uint256);
    function unwrapTo(uint256 amount, address to) external returns (uint256);
    function unwrap(uint256 amount) external returns (uint256);
}
pragma solidity =0.6.6;
// 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');
    }
}
// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
import '../core/ICore.sol';
/// @title CoreRef interface
interface ICoreRef {
    event CoreUpdate(address indexed _core);
    function setCore(address coreAddress) external;
    function pause() external;
    function unpause() external;
    function core() external view returns (ICore);
}

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

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    (at your option) any later version.

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    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.

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    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>.

*/

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.25;
import {AllowanceHolderBase} from "./AllowanceHolderBase.sol";
import {TransientStorage} from "./TransientStorage.sol";
/// @custom:security-contact security@0x.org
contract AllowanceHolder is TransientStorage, AllowanceHolderBase {
    constructor() {
        require(address(this) == 0x0000000000001fF3684f28c67538d4D072C22734 || block.chainid == 31337);
    }
    /// @inheritdoc AllowanceHolderBase
    function exec(address operator, address token, uint256 amount, address payable target, bytes calldata data)
        internal
        override
        returns (bytes memory)
    {
        (bytes memory result, address sender, TSlot allowance) = _exec(operator, token, amount, target, data);
        // EIP-3074 seems unlikely
        if (sender != tx.origin) {
            _set(allowance, 0);
        }
        return result;
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.25;
import {IAllowanceHolder} from "./IAllowanceHolder.sol";
import {IERC20} from "../IERC20.sol";
import {SafeTransferLib} from "../vendor/SafeTransferLib.sol";
import {CheckCall} from "../utils/CheckCall.sol";
import {FreeMemory} from "../utils/FreeMemory.sol";
import {TransientStorageLayout} from "./TransientStorageLayout.sol";
/// @notice Thrown when validating the target, avoiding executing against an ERC20 directly
error ConfusedDeputy();
abstract contract AllowanceHolderBase is TransientStorageLayout, FreeMemory {
    using SafeTransferLib for IERC20;
    using CheckCall for address payable;
    function _rejectIfERC20(address payable maybeERC20, bytes calldata data) private view DANGEROUS_freeMemory {
        // We could just choose a random address for this check, but to make
        // confused deputy attacks harder for tokens that might be badly behaved
        // (e.g. tokens with blacklists), we choose to copy the first argument
        // out of `data` and mask it as an address. If there isn't enough
        // `data`, we use 0xdead instead.
        address target;
        if (data.length > 0x10) {
            target = address(uint160(bytes20(data[0x10:])));
        }
        // EIP-1352 (not adopted) specifies 0xffff as the maximum precompile
        if (target <= address(0xffff)) {
            // 0xdead is a conventional burn address; we assume that it is not treated specially
            target = address(0xdead);
        }
        bytes memory testData = abi.encodeCall(IERC20.balanceOf, target);
        if (maybeERC20.checkCall(testData, 0x20)) revert ConfusedDeputy();
    }
    function _msgSender() private view returns (address sender) {
        if ((sender = msg.sender) == address(this)) {
            assembly ("memory-safe") {
                sender := shr(0x60, calldataload(sub(calldatasize(), 0x14)))
            }
        }
    }
    /// @dev This virtual function provides the implementation for the function
    ///      of the same name in `IAllowanceHolder`. It is unimplemented in this
    ///      base contract to accommodate the customization required to support
    ///      both chains that have EIP-1153 (transient storage) and those that
    ///      don't.
    function exec(address operator, address token, uint256 amount, address payable target, bytes calldata data)
        internal
        virtual
        returns (bytes memory result);
    /// @dev This is the majority of the implementation of IAllowanceHolder.exec
    ///      . The arguments have the same meaning as documented there.
    /// @return result
    /// @return sender The (possibly forwarded) message sender that is
    ///                requesting the allowance be set. Provided to avoid
    ///                duplicated computation in customized `exec`
    /// @return allowance The slot where the ephemeral allowance is
    ///                   stored. Provided to avoid duplicated computation in
    ///                   customized `exec`
    function _exec(address operator, address token, uint256 amount, address payable target, bytes calldata data)
        internal
        returns (bytes memory result, address sender, TSlot allowance)
    {
        // This contract has no special privileges, except for the allowances it
        // holds. In order to prevent abusing those allowances, we prohibit
        // sending arbitrary calldata (doing `target.call(data)`) to any
        // contract that might be an ERC20.
        _rejectIfERC20(target, data);
        sender = _msgSender();
        allowance = _ephemeralAllowance(operator, sender, token);
        _set(allowance, amount);
        // For gas efficiency we're omitting a bunch of checks here. Notably,
        // we're omitting the check that `address(this)` has sufficient value to
        // send (we know it does), and we're omitting the check that `target`
        // contains code (we already checked in `_rejectIfERC20`).
        assembly ("memory-safe") {
            result := mload(0x40)
            calldatacopy(result, data.offset, data.length)
            // ERC-2771 style msgSender forwarding https://eips.ethereum.org/EIPS/eip-2771
            mstore(add(result, data.length), shl(0x60, sender))
            let success := call(gas(), target, callvalue(), result, add(data.length, 0x14), 0x00, 0x00)
            let ptr := add(result, 0x20)
            returndatacopy(ptr, 0x00, returndatasize())
            switch success
            case 0 { revert(ptr, returndatasize()) }
            default {
                mstore(result, returndatasize())
                mstore(0x40, add(ptr, returndatasize()))
            }
        }
    }
    /// @dev This provides the implementation of the function of the same name
    ///      in `IAllowanceHolder`.
    function transferFrom(address token, address owner, address recipient, uint256 amount) internal {
        // msg.sender is the assumed and later validated operator
        TSlot allowance = _ephemeralAllowance(msg.sender, owner, token);
        // validation of the ephemeral allowance for operator, owner, token via
        // uint underflow
        _set(allowance, _get(allowance) - amount);
        // `safeTransferFrom` does not check that `token` actually contains
        // code. It is the responsibility of integrating code to check for that
        // if vacuous success is a security concern.
        IERC20(token).safeTransferFrom(owner, recipient, amount);
    }
    fallback() external payable {
        uint256 selector;
        assembly ("memory-safe") {
            selector := shr(0xe0, calldataload(0x00))
        }
        if (selector == uint256(uint32(IAllowanceHolder.transferFrom.selector))) {
            address token;
            address owner;
            address recipient;
            uint256 amount;
            assembly ("memory-safe") {
                // We do not validate `calldatasize()`. If the calldata is short
                // enough that `amount` is null, this call is a harmless no-op.
                let err := callvalue()
                token := calldataload(0x04)
                err := or(err, shr(0xa0, token))
                owner := calldataload(0x24)
                err := or(err, shr(0xa0, owner))
                recipient := calldataload(0x44)
                err := or(err, shr(0xa0, recipient))
                if err { revert(0x00, 0x00) }
                amount := calldataload(0x64)
            }
            transferFrom(token, owner, recipient, amount);
            // return true;
            assembly ("memory-safe") {
                mstore(0x00, 0x01)
                return(0x00, 0x20)
            }
        } else if (selector == uint256(uint32(IAllowanceHolder.exec.selector))) {
            address operator;
            address token;
            uint256 amount;
            address payable target;
            bytes calldata data;
            assembly ("memory-safe") {
                // We do not validate `calldatasize()`. If the calldata is short
                // enough that `data` is null, it will alias `operator`. This
                // results in either an OOG (because `operator` encodes a
                // too-long `bytes`) or is a harmless no-op (because `operator`
                // encodes a valid length, but not an address capable of making
                // calls). If the calldata is _so_ sort that `target` is null,
                // we will revert because it contains no code.
                operator := calldataload(0x04)
                let err := shr(0xa0, operator)
                token := calldataload(0x24)
                err := or(err, shr(0xa0, token))
                amount := calldataload(0x44)
                target := calldataload(0x64)
                err := or(err, shr(0xa0, target))
                if err { revert(0x00, 0x00) }
                // We perform no validation that `data` is reasonable.
                data.offset := add(0x04, calldataload(0x84))
                data.length := calldataload(data.offset)
                data.offset := add(0x20, data.offset)
            }
            bytes memory result = exec(operator, token, amount, target, data);
            // return result;
            assembly ("memory-safe") {
                let returndata := sub(result, 0x20)
                mstore(returndata, 0x20)
                return(returndata, add(0x40, mload(result)))
            }
        } else if (selector == uint256(uint32(IERC20.balanceOf.selector))) {
            // balanceOf(address) reverts with a single byte of returndata,
            // making it more gas efficient to pass the `_rejectERC20` check
            assembly ("memory-safe") {
                revert(0x00, 0x01)
            }
        } else {
            // emulate standard Solidity behavior
            assembly ("memory-safe") {
                revert(0x00, 0x00)
            }
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.25;
import {TransientStorageBase} from "./TransientStorageBase.sol";
abstract contract TransientStorage is TransientStorageBase {
    function _get(TSlot s) internal view override returns (uint256 r) {
        assembly ("memory-safe") {
            r := tload(s)
        }
    }
    function _set(TSlot s, uint256 v) internal override {
        assembly ("memory-safe") {
            tstore(s, v)
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.25;
interface IAllowanceHolder {
    /// @notice Executes against `target` with the `data` payload. Prior to execution, token permits
    ///         are temporarily stored for the duration of the transaction. These permits can be
    ///         consumed by the `operator` during the execution
    /// @notice `operator` consumes the funds during its operations by calling back into
    ///         `AllowanceHolder` with `transferFrom`, consuming a token permit.
    /// @dev Neither `exec` nor `transferFrom` check that `token` contains code.
    /// @dev msg.sender is forwarded to target appended to the msg data (similar to ERC-2771)
    /// @param operator An address which is allowed to consume the token permits
    /// @param token The ERC20 token the caller has authorised to be consumed
    /// @param amount The quantity of `token` the caller has authorised to be consumed
    /// @param target A contract to execute operations with `data`
    /// @param data The data to forward to `target`
    /// @return result The returndata from calling `target` with `data`
    /// @notice If calling `target` with `data` reverts, the revert is propagated
    function exec(address operator, address token, uint256 amount, address payable target, bytes calldata data)
        external
        payable
        returns (bytes memory result);
    /// @notice The counterpart to `exec` which allows for the consumption of token permits later
    ///         during execution
    /// @dev *DOES NOT* check that `token` contains code. This function vacuously succeeds if
    ///      `token` is empty.
    /// @dev can only be called by the `operator` previously registered in `exec`
    /// @param token The ERC20 token to transfer
    /// @param owner The owner of tokens to transfer
    /// @param recipient The destination/beneficiary of the ERC20 `transferFrom`
    /// @param amount The quantity of `token` to transfer`
    /// @return true
    function transferFrom(address token, address owner, address recipient, uint256 amount) external returns (bool);
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.25;
interface IERC20 {
    function totalSupply() external view returns (uint256);
    function balanceOf(address) external view returns (uint256);
    function transfer(address, uint256) external returns (bool);
    function transferFrom(address, address, uint256) external returns (bool);
    function approve(address, uint256) external returns (bool);
    function allowance(address, address) external view returns (uint256);
    event Transfer(address indexed, address indexed, uint256);
    event Approval(address indexed, address indexed, uint256);
}
interface IERC20Meta is IERC20 {
    function name() external view returns (string memory);
    function symbol() external view returns (string memory);
    function decimals() external view returns (uint8);
}
// SPDX-License-Identifier: AGPL-3.0-only
pragma solidity >=0.8.25;
import {IERC20} from "../IERC20.sol";
/// @notice Safe ETH and ERC20 transfer library that gracefully handles missing return values.
/// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/utils/SafeTransferLib.sol)
/// @dev Use with caution! Some functions in this library knowingly create dirty bits at the destination of the free memory pointer.
/// @dev Note that none of the functions in this library check that a token has code at all! That responsibility is delegated to the caller.
library SafeTransferLib {
    uint32 private constant _TRANSFER_FROM_FAILED_SELECTOR = 0x7939f424; // bytes4(keccak256("TransferFromFailed()"))
    uint32 private constant _TRANSFER_FAILED_SELECTOR = 0x90b8ec18; // bytes4(keccak256("TransferFailed()"))
    uint32 private constant _APPROVE_FAILED_SELECTOR = 0x3e3f8f73; // bytes4(keccak256("ApproveFailed()"))
    /*//////////////////////////////////////////////////////////////
                             ETH OPERATIONS
    //////////////////////////////////////////////////////////////*/
    function safeTransferETH(address payable to, uint256 amount) internal {
        assembly ("memory-safe") {
            // Transfer the ETH and store if it succeeded or not.
            if iszero(call(gas(), to, amount, 0, 0, 0, 0)) {
                let freeMemoryPointer := mload(0x40)
                returndatacopy(freeMemoryPointer, 0, returndatasize())
                revert(freeMemoryPointer, returndatasize())
            }
        }
    }
    /*//////////////////////////////////////////////////////////////
                            ERC20 OPERATIONS
    //////////////////////////////////////////////////////////////*/
    function safeTransferFrom(IERC20 token, address from, address to, uint256 amount) internal {
        assembly ("memory-safe") {
            // Get a pointer to some free memory.
            let freeMemoryPointer := mload(0x40)
            // Write the abi-encoded calldata into memory, beginning with the function selector.
            mstore(freeMemoryPointer, 0x23b872dd00000000000000000000000000000000000000000000000000000000)
            mstore(add(freeMemoryPointer, 4), and(from, 0xffffffffffffffffffffffffffffffffffffffff)) // Append and mask the "from" argument.
            mstore(add(freeMemoryPointer, 36), and(to, 0xffffffffffffffffffffffffffffffffffffffff)) // Append and mask the "to" argument.
            mstore(add(freeMemoryPointer, 68), amount) // Append the "amount" argument. Masking not required as it's a full 32 byte type.
            // We use 100 because the length of our calldata totals up like so: 4 + 32 * 3.
            // We use 0 and 32 to copy up to 32 bytes of return data into the scratch space.
            if iszero(call(gas(), token, 0, freeMemoryPointer, 100, 0, 32)) {
                returndatacopy(freeMemoryPointer, 0, returndatasize())
                revert(freeMemoryPointer, returndatasize())
            }
            // We check that the call either returned exactly 1 (can't just be non-zero data), or had no
            // return data.
            if iszero(or(and(eq(mload(0), 1), gt(returndatasize(), 31)), iszero(returndatasize()))) {
                mstore(0, _TRANSFER_FROM_FAILED_SELECTOR)
                revert(0x1c, 0x04)
            }
        }
    }
    function safeTransfer(IERC20 token, address to, uint256 amount) internal {
        assembly ("memory-safe") {
            // Get a pointer to some free memory.
            let freeMemoryPointer := mload(0x40)
            // Write the abi-encoded calldata into memory, beginning with the function selector.
            mstore(freeMemoryPointer, 0xa9059cbb00000000000000000000000000000000000000000000000000000000)
            mstore(add(freeMemoryPointer, 4), and(to, 0xffffffffffffffffffffffffffffffffffffffff)) // Append and mask the "to" argument.
            mstore(add(freeMemoryPointer, 36), amount) // Append the "amount" argument. Masking not required as it's a full 32 byte type.
            // We use 68 because the length of our calldata totals up like so: 4 + 32 * 2.
            // We use 0 and 32 to copy up to 32 bytes of return data into the scratch space.
            if iszero(call(gas(), token, 0, freeMemoryPointer, 68, 0, 32)) {
                returndatacopy(freeMemoryPointer, 0, returndatasize())
                revert(freeMemoryPointer, returndatasize())
            }
            // We check that the call either returned exactly 1 (can't just be non-zero data), or had no
            // return data.
            if iszero(or(and(eq(mload(0), 1), gt(returndatasize(), 31)), iszero(returndatasize()))) {
                mstore(0, _TRANSFER_FAILED_SELECTOR)
                revert(0x1c, 0x04)
            }
        }
    }
    function safeApprove(IERC20 token, address to, uint256 amount) internal {
        assembly ("memory-safe") {
            // Get a pointer to some free memory.
            let freeMemoryPointer := mload(0x40)
            // Write the abi-encoded calldata into memory, beginning with the function selector.
            mstore(freeMemoryPointer, 0x095ea7b300000000000000000000000000000000000000000000000000000000)
            mstore(add(freeMemoryPointer, 4), and(to, 0xffffffffffffffffffffffffffffffffffffffff)) // Append and mask the "to" argument.
            mstore(add(freeMemoryPointer, 36), amount) // Append the "amount" argument. Masking not required as it's a full 32 byte type.
            // We use 68 because the length of our calldata totals up like so: 4 + 32 * 2.
            // We use 0 and 32 to copy up to 32 bytes of return data into the scratch space.
            if iszero(call(gas(), token, 0, freeMemoryPointer, 68, 0, 32)) {
                returndatacopy(freeMemoryPointer, 0, returndatasize())
                revert(freeMemoryPointer, returndatasize())
            }
            // We check that the call either returned exactly 1 (can't just be non-zero data), or had no
            // return data.
            if iszero(or(and(eq(mload(0), 1), gt(returndatasize(), 31)), iszero(returndatasize()))) {
                mstore(0, _APPROVE_FAILED_SELECTOR)
                revert(0x1c, 0x04)
            }
        }
    }
    function safeApproveIfBelow(IERC20 token, address spender, uint256 amount) internal {
        uint256 allowance = token.allowance(address(this), spender);
        if (allowance < amount) {
            if (allowance != 0) {
                safeApprove(token, spender, 0);
            }
            safeApprove(token, spender, type(uint256).max);
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.25;
library CheckCall {
    /**
     * @notice `staticcall` another contract. Check the length of the return without reading it.
     * @dev contains protections against EIP-150-induced insufficient gas griefing
     * @dev reverts iff the target is not a contract or we encounter an out-of-gas
     * @return success true iff the call succeeded and returned at least `minReturnBytes` of return
     *                 data
     * @param target the contract (reverts if non-contract) on which to make the `staticcall`
     * @param data the calldata to pass
     * @param minReturnBytes `success` is false if the call doesn't return at least this much return
     *                       data
     */
    function checkCall(address target, bytes memory data, uint256 minReturnBytes)
        internal
        view
        returns (bool success)
    {
        assembly ("memory-safe") {
            let beforeGas
            {
                let offset := add(data, 0x20)
                let length := mload(data)
                beforeGas := gas()
                success := staticcall(gas(), target, offset, length, 0x00, 0x00)
            }
            // `verbatim` can't work in inline assembly. Assignment of a value to a variable costs
            // gas (although how much is unpredictable because it depends on the Yul/IR optimizer),
            // as does the `GAS` opcode itself. Therefore, the `gas()` below returns less than the
            // actual amount of gas available for computation at the end of the call. Also
            // `beforeGas` above is exclusive of the preparing of the stack for `staticcall` as well
            // as the gas costs of the `staticcall` paid by the caller (e.g. cold account
            // access). All this makes the check below slightly too conservative. However, we do not
            // correct this because the correction would become outdated (possibly too permissive)
            // if the opcodes are repriced.
            let afterGas := gas()
            for {} 1 {} {
                if iszero(returndatasize()) {
                    // The absence of returndata means that it's possible that either we called an
                    // address without code or that the call reverted due to out-of-gas. We must
                    // check.
                    switch success
                    case 0 {
                        // Check whether the call reverted due to out-of-gas.
                        // https://eips.ethereum.org/EIPS/eip-150
                        // https://ronan.eth.limo/blog/ethereum-gas-dangers/
                        // We apply the "all but one 64th" rule twice because `target` could
                        // plausibly be a proxy. We apply it only twice because we assume only a
                        // single level of indirection.
                        let remainingGas := shr(6, beforeGas)
                        remainingGas := add(remainingGas, shr(6, sub(beforeGas, remainingGas)))
                        if iszero(lt(remainingGas, afterGas)) {
                            // The call failed due to not enough gas left. We deliberately consume
                            // all remaining gas with `invalid` (instead of `revert`) to make this
                            // failure distinguishable to our caller.
                            invalid()
                        }
                        // `success` is false because the call reverted
                    }
                    default {
                        // Check whether we called an address with no code (gas expensive).
                        if iszero(extcodesize(target)) { revert(0x00, 0x00) }
                        // We called a contract which returned no data; this is only a success if we
                        // were expecting no data.
                        success := iszero(minReturnBytes)
                    }
                    break
                }
                // The presence of returndata indicates that we definitely executed code. It also
                // means that the call didn't revert due to out-of-gas, if it reverted. We can omit
                // a bunch of checks.
                success := gt(success, lt(returndatasize(), minReturnBytes))
                break
            }
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.25;
abstract contract FreeMemory {
    modifier DANGEROUS_freeMemory() {
        uint256 freeMemPtr;
        assembly ("memory-safe") {
            freeMemPtr := mload(0x40)
        }
        _;
        assembly ("memory-safe") {
            mstore(0x40, freeMemPtr)
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.25;
import {TransientStorageBase} from "./TransientStorageBase.sol";
abstract contract TransientStorageLayout is TransientStorageBase {
    /// @dev The key for this ephemeral allowance is keccak256(abi.encodePacked(operator, owner, token)).
    function _ephemeralAllowance(address operator, address owner, address token) internal pure returns (TSlot r) {
        assembly ("memory-safe") {
            let ptr := mload(0x40)
            mstore(0x28, token)
            mstore(0x14, owner)
            mstore(0x00, operator)
            // allowance slot is keccak256(abi.encodePacked(operator, owner, token))
            r := keccak256(0x0c, 0x3c)
            // restore dirtied free pointer
            mstore(0x40, ptr)
        }
    }
}
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.25;
abstract contract TransientStorageBase {
    type TSlot is bytes32;
    function _get(TSlot s) internal view virtual returns (uint256);
    function _set(TSlot s, uint256 v) internal virtual;
}