// Copyright (c) 2022 EverRise Pte Ltd. All rights reserved.
// EverRise licenses this file to you under the MIT license.
/*
 The EverRise token is the keystone in the EverRise Ecosytem of dApps
 and the overaching key that unlocks multi-blockchain unification via
 the EverBridge.

 On EverRise token transactions 6% buyback and business development fees are collected:

 * 4% for token Buyback from the market, with bought back tokens directly
      distributed as ve-staking rewards
 * 2% for Business Development (Development, Sustainability and Marketing)
  ________                              _______   __
 /        |                            /       \ /  |
 $$$$$$$$/__     __  ______    ______  $$$$$$$  |$$/   _______   ______  v3.14159265
 $$ |__  /  \   /  |/      \  /      \ $$ |__$$ |/  | /       | /      \
 $$    | $$  \ /$$//$$$$$$  |/$$$$$$  |$$    $$< $$ |/$$$$$$$/ /$$$$$$  |
 $$$$$/   $$  /$$/ $$    $$ |$$ |  $$/ $$$$$$$  |$$ |$$      \ $$    $$ |
 $$ |_____ $$ $$/  $$$$$$$$/ $$ |      $$ |  $$ |$$ | $$$$$$  |$$$$$$$$/
 $$       | $$$/   $$       |$$ |      $$ |  $$ |$$ |/     $$/ $$       |
 $$$$$$$$/   $/     $$$$$$$/ $$/       $$/   $$/ $$/ $$$$$$$/   $$$$$$$/ Magnum opus

 Learn more about EverRise and the EverRise Ecosystem of dApps and
 how our utilities and partners can help protect your investors
 and help your project grow: https://everrise.com
*/

// SPDX-License-Identifier: MIT

pragma solidity 0.8.13;

error NotContractAddress();             // 0xd9716e43
error NoSameBlockSandwichTrades();      // 0x5fe87cb3
error TransferTooLarge();               // 0x1b97a875
error AmountLargerThanUnlockedAmount(); // 0x170abf7c
error TokenNotStarted();                // 0xd87a63e0
error TokenAlreadyStarted();            // 0xe529091f
error SandwichTradesAreDisallowed();    // 0xe069ee1d
error AmountLargerThanAvailable();      // 0xbb296109
error StakeCanOnlyBeExtended();         // 0x73f7040a
error NotStakeContractRequesting();     // 0x2ace6531
error NotEnoughToCoverStakeFee();       // 0x627554ed
error NotZeroAddress();                 // 0x66385fa3
error CallerNotApproved();              // 0x4014f1a5
error InvalidAddress();                 // 0xe6c4247b
error CallerNotOwner();                 // 0x5cd83192
error NotZero();                        // 0x0295aa98
error LiquidityIsLocked();              // 0x6bac637f
error LiquidityAddOwnerOnly();          // 0x878d6363
error Overflow();                       // 0x35278d12
error WalletLocked();                   // 0xd550ed24
error LockTimeTooLong();                // 0xb660e89a
error LockTimeTooShort();               // 0x6badcecf
error NotLocked();                      // 0x1834e265
error AmountMustBeGreaterThanZero();    // 0x5e85ae73
error Expired();                        // 0x203d82d8
error InvalidSignature();               // 0x8baa579f
error AmountLargerThanAllowance();      // 0x9b144c57
error AmountOutOfRange();               // 0xc64200e9
error Unlocked();                       // 0x19aad371
error FailedEthSend();                  // 0xb5747cc7

// File: EverRise-v3/Interfaces/IERC2612-Permit.sol

pragma solidity 0.8.13;
interface IERC2612 {
    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external;
    function nonces(address owner) external view returns (uint256);
    function DOMAIN_SEPARATOR() external view returns (bytes32);
}

// File: EverRise-v3/Interfaces/IERC173-Ownable.sol

interface IOwnable {
    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
    function owner() external view returns (address);
    function transferOwnership(address newOwner) external;
}

// File: EverRise-v3/Abstract/Context.sol

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


// File: EverRise-v3/Interfaces/IERC721-Nft.sol

interface IERC721 /* is ERC165 */ {
    event Transfer(address indexed _from, address indexed _to, uint256 indexed _tokenId);
    event Approval(address indexed _owner, address indexed _approved, uint256 indexed _tokenId);
    event ApprovalForAll(address indexed _owner, address indexed _operator, bool _approved);
    function balanceOf(address _owner) external view returns (uint256);
    function ownerOf(uint256 _tokenId) external view returns (address);
    function safeTransferFrom(address _from, address _to, uint256 _tokenId, bytes calldata data) external payable;
    function safeTransferFrom(address _from, address _to, uint256 _tokenId) external payable;
    function transferFrom(address _from, address _to, uint256 _tokenId) external payable;
    function approve(address _approved, uint256 _tokenId) external payable;
    function setApprovalForAll(address _operator, bool _approved) external;
    function getApproved(uint256 _tokenId) external view returns (address);
    function isApprovedForAll(address _owner, address _operator) external view returns (bool);
}

// File: EverRise-v3/Interfaces/InftEverRise.sol

struct StakingDetails {
    uint96 initialTokenAmount;    // Max 79 Bn tokens
    uint96 withdrawnAmount;       // Max 79 Bn tokens
    uint48 depositTime;           // 8 M years
    uint8 numOfMonths;            // Max 256 month period
    uint8 achievementClaimed;
    // 256 bits, 20000 gwei gas
    address stakerAddress;        // 160 bits (96 bits remaining)
    uint32 nftId;                 // Max 4 Bn nfts issued
    uint32 lookupIndex;           // Max 4 Bn active stakes
    uint24 stakerIndex;           // Max 16 M active stakes per wallet
    uint8 isActive;
    // 256 bits, 20000 gwei gas
} // Total 512 bits, 40000 gwei gas

interface InftEverRise is IERC721 {
    function voteEscrowedBalance(address account) external view returns (uint256);
    function unclaimedRewardsBalance(address account) external view returns (uint256);
    function totalAmountEscrowed() external view returns (uint256);
    function totalAmountVoteEscrowed() external view returns (uint256);
    function totalRewardsDistributed() external view returns (uint256);
    function totalRewardsUnclaimed() external view returns (uint256);

    function createRewards(uint256 tAmount) external;

    function getNftData(uint256 id) external view returns (StakingDetails memory);
    function enterStaking(address fromAddress, uint96 amount, uint8 numOfMonths) external returns (uint32 nftId);
    function leaveStaking(address fromAddress, uint256 id, bool overrideNotClaimed) external returns (uint96 amount);
    function earlyWithdraw(address fromAddress, uint256 id, uint96 amount) external returns (uint32 newNftId, uint96 penaltyAmount);
    function withdraw(address fromAddress, uint256 id, uint96 amount, bool overrideNotClaimed) external returns (uint32 newNftId);
    function bridgeStakeNftOut(address fromAddress, uint256 id) external returns (uint96 amount);
    function bridgeOrAirdropStakeNftIn(address toAddress, uint96 depositAmount, uint8 numOfMonths, uint48 depositTime, uint96 withdrawnAmount, uint96 rewards, bool achievementClaimed) external returns (uint32 nftId);
    function addStaker(address staker, uint256 nftId) external;
    function removeStaker(address staker, uint256 nftId) external;
    function reissueStakeNft(address staker, uint256 oldNftId, uint256 newNftId) external;
    function increaseStake(address staker, uint256 nftId, uint96 amount) external returns (uint32 newNftId, uint96 original, uint8 numOfMonths);
    function splitStake(uint256 id, uint96 amount) external payable returns (uint32 newNftId0, uint32 newNftId1);
    function claimAchievement(address staker, uint256 nftId) external returns (uint32 newNftId);
    function stakeCreateCost() external view returns (uint256);
    function approve(address owner, address _operator, uint256 nftId) external;
}
// File: EverRise-v3/Interfaces/IEverRiseWallet.sol

struct ApprovalChecks {
    // Prevent permits being reused (IERC2612)
    uint64 nonce;
    // Allow revoke all spenders/operators approvals in single txn
    uint32 nftCheck;
    uint32 tokenCheck;
    // Allow auto timeout on approvals
    uint16 autoRevokeNftHours;
    uint16 autoRevokeTokenHours;
    // Allow full wallet locking of all transfers
    uint48 unlockTimestamp;
}

struct Allowance {
    uint128 tokenAmount;
    uint32 nftCheck;
    uint32 tokenCheck;
    uint48 timestamp;
    uint8 nftApproval;
    uint8 tokenApproval;
}

interface IEverRiseWallet {
    event RevokeAllApprovals(address indexed account, bool tokens, bool nfts);
    event SetApprovalAutoTimeout(address indexed account, uint16 tokensHrs, uint16 nftsHrs);
    event LockWallet(address indexed account, address altAccount, uint256 length);
    event LockWalletExtend(address indexed account, uint256 length);
}
// File: EverRise-v3/Interfaces/IUniswap.sol

interface IUniswapV2Factory {
    event PairCreated(address indexed token0, address indexed token1, address pair, uint256);
    function createPair(address tokenA, address tokenB) external returns (address pair);
    function setFeeTo(address) external;
    function setFeeToSetter(address) external;
    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(uint256) external view returns (address pair);
    function allPairsLength() external view returns (uint256);
}

interface IUniswapV2Pair {
    event Approval(address indexed owner, address indexed spender, uint256 value);
    event Transfer(address indexed from, address indexed to, uint256 value);
    event Burn(address indexed sender, uint256 amount0, uint256 amount1, address indexed to);
    event Swap(address indexed sender, uint256 amount0In, uint256 amount1In, uint256 amount0Out, uint256 amount1Out, address indexed to);
    event Sync(uint112 reserve0, uint112 reserve1);
    function approve(address spender, uint256 value) external returns (bool);
    function transfer(address to, uint256 value) external returns (bool);
    function transferFrom(address from, address to, uint256 value) external returns (bool);
    function burn(address to) external returns (uint256 amount0, uint256 amount1);
    function swap(uint256 amount0Out, uint256 amount1Out, address to, bytes calldata data) external;
    function skim(address to) external;
    function sync() external;
    function initialize(address, address) external;
    function permit(address owner, address spender, uint256 value, uint256 deadline, uint8 v, bytes32 r,bytes32 s) external;
    function totalSupply() external view returns (uint256);
    function balanceOf(address owner) external view returns (uint256);
    function allowance(address owner, address spender) external view returns (uint256);
    function DOMAIN_SEPARATOR() external view returns (bytes32);
    function nonces(address owner) external view returns (uint256);
    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 (uint256);
    function price1CumulativeLast() external view returns (uint256);
    function kLast() external view returns (uint256);
    function name() external pure returns (string memory);
    function symbol() external pure returns (string memory);
    function decimals() external pure returns (uint8);
    function PERMIT_TYPEHASH() external pure returns (bytes32);
    function MINIMUM_LIQUIDITY() external pure returns (uint256);
}

interface IUniswapV2Router01 {
    function addLiquidityETH(address token, uint256 amountTokenDesired, uint256 amountTokenMin, uint256 amountETHMin, address to, uint256 deadline) external payable returns (uint256 amountToken, uint256 amountETH, uint256 liquidity);
    function swapETHForExactTokens(uint256 amountOut, address[] calldata path, address to, uint256 deadline) external payable returns (uint256[] memory amounts);
    function swapExactETHForTokens(uint256 amountOutMin, address[] calldata path, address to, uint256 deadline) external payable returns (uint256[] memory amounts);
    function addLiquidity(address tokenA, address tokenB, uint256 amountADesired, uint256 amountBDesired, uint256 amountAMin, uint256 amountBMin, address to, uint256 deadline) external returns (uint256 amountA, uint256 amountB, uint256 liquidity);
    function removeLiquidity(address tokenA, address tokenB, uint256 liquidity, uint256 amountAMin, uint256 amountBMin, address to, uint256 deadline) external returns (uint256 amountA, uint256 amountB);
    function removeLiquidityETH(address token, uint256 liquidity, uint256 amountTokenMin, uint256 amountETHMin, address to, uint256 deadline) external returns (uint256 amountToken, uint256 amountETH);
    function removeLiquidityWithPermit(address tokenA, address tokenB, uint256 liquidity, uint256 amountAMin, uint256 amountBMin, address to, uint256 deadline, bool approveMax, uint8 v, bytes32 r, bytes32 s) external returns (uint256 amountA, uint256 amountB);
    function removeLiquidityETHWithPermit(address token, uint256 liquidity, uint256 amountTokenMin, uint256 amountETHMin, address to, uint256 deadline, bool approveMax, uint8 v, bytes32 r, bytes32 s) external returns (uint256 amountToken, uint256 amountETH);
    function swapExactTokensForTokens(uint256 amountIn, uint256 amountOutMin, address[] calldata path, address to, uint256 deadline) external returns (uint256[] memory amounts);
    function swapTokensForExactTokens(uint256 amountOut, uint256 amountInMax, address[] calldata path, address to, uint256 deadline) external returns (uint256[] memory amounts);
    function swapTokensForExactETH(uint256 amountOut, uint256 amountInMax, address[] calldata path, address to, uint256 deadline) external returns (uint256[] memory amounts);
    function swapExactTokensForETH(uint256 amountIn, uint256 amountOutMin, address[] calldata path, address to, uint256 deadline) external returns (uint256[] memory amounts);
    function getAmountsOut(uint256 amountIn, address[] calldata path) external view returns (uint256[] memory amounts);
    function getAmountsIn(uint256 amountOut, address[] calldata path) external view returns (uint256[] memory amounts);
    function factory() external pure returns (address);
    function WETH() external pure returns (address);
    function quote(uint256 amountA, uint256 reserveA, uint256 reserveB) external pure returns (uint256 amountB);
    function getAmountOut(uint256 amountIn, uint256 reserveIn, uint256 reserveOut) external pure returns (uint256 amountOut);
    function getAmountIn(uint256 amountOut, uint256 reserveIn, uint256 reserveOut) external pure returns (uint256 amountIn);
}

interface IUniswapV2Router02 is IUniswapV2Router01 {
    function removeLiquidityETHSupportingFeeOnTransferTokens(address token, uint256 liquidity, uint256 amountTokenMin, uint256 amountETHMin, address to, uint256 deadline) external returns (uint256 amountETH);
    function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(address token, uint256 liquidity, uint256 amountTokenMin, uint256 amountETHMin, address to, uint256 deadline, bool approveMax, uint8 v, bytes32 r, bytes32 s) external returns (uint256 amountETH);
    function swapExactTokensForTokensSupportingFeeOnTransferTokens(uint256 amountIn, uint256 amountOutMin, address[] calldata path, address to, uint256 deadline) external;
    function swapExactETHForTokensSupportingFeeOnTransferTokens(uint256 amountOutMin, address[] calldata path, address to, uint256 deadline) external payable;
    function swapExactTokensForETHSupportingFeeOnTransferTokens(uint256 amountIn, uint256 amountOutMin, address[] calldata path, address to, uint256 deadline ) external;
}
// File: EverRise-v3/Abstract/ErrorNotZeroAddress.sol

contract Ownable is IOwnable, Context {
    address public owner;

    function _onlyOwner() private view {
        if (owner != _msgSender()) revert CallerNotOwner();
    }

    modifier onlyOwner() {
        _onlyOwner();
        _;
    }

    constructor() {
        address msgSender = _msgSender();
        owner = msgSender;
        emit OwnershipTransferred(address(0), msgSender);
    }

    // Allow contract ownership and access to contract onlyOwner functions
    // to be locked using EverOwn with control gated by community vote.
    //
    // EverRise ($RISE) stakers become voting members of the
    // decentralized autonomous organization (DAO) that controls access
    // to the token contract via the EverRise Ecosystem dApp EverOwn
    function transferOwnership(address newOwner) external virtual onlyOwner {
        if (newOwner == address(0)) revert NotZeroAddress();

        emit OwnershipTransferred(owner, newOwner);
        owner = newOwner;
    }
}
// File: EverRise-v3/Abstract/EverRiseRoles.sol


abstract contract EverRiseRoles is Ownable {
    mapping (Role => mapping (address => bool)) public roles;

    enum Role 
    { 
        NotValidRole, 
        BuyBack, 
        NftBridge,
        Limits, 
        Liquidity, 
        Fees,
        Exchanges,
        CrossChainBuyback,
        Upgrader
    }

    event ControlAdded(address indexed controller, Role indexed role);
    event ControlRemoved(address indexed controller, Role indexed role);
    
    function _onlyController(Role role) private view {
        if (!roles[role][_msgSender()]) revert CallerNotApproved();
    }
    
    modifier onlyController(Role role) {
        _onlyController(role);
        _;
    }

    constructor() {
        address deployer = _msgSender();
        ownerRoles(deployer, true);
    }
    
    function transferOwnership(address newOwner) override external onlyOwner {
        if (newOwner == address(0)) revert NotZeroAddress();

        address previousOwner = owner;
        ownerRoles(previousOwner, false);
        ownerRoles(newOwner, true);

        owner = newOwner;

        emit OwnershipTransferred(previousOwner, newOwner);
    }

    function ownerRoles(address _owner, bool enable) private {
        roles[Role.BuyBack][_owner] = enable;
        roles[Role.NftBridge][_owner] = enable;
        roles[Role.Limits][_owner] = enable;
        roles[Role.Liquidity][_owner] = enable;
        roles[Role.Fees][_owner] = enable;
        roles[Role.Exchanges][_owner] = enable;
        roles[Role.CrossChainBuyback][_owner] = enable;
        roles[Role.Upgrader][_owner] = enable;
    }

    function addControlRole(address newController, Role role) external onlyOwner
    {
        if (role == Role.NotValidRole) revert NotZero();
        if (newController == address(0)) revert NotZeroAddress();

        roles[role][newController] = true;

        emit ControlAdded(newController, role);
    }

    function removeControlRole(address oldController, Role role) external onlyOwner
    {
        if (role == Role.NotValidRole) revert NotZero();
        if (oldController == address(0)) revert NotZeroAddress();

        roles[role][oldController] = false;

        emit ControlRemoved(oldController, role);
    }
}
// File: EverRise-v3/Abstract/EverRiseLib.sol

library EverRiseAddressNumberLib {
    function toUint96(uint256 value) internal pure returns (uint96) {
        if (value > type(uint96).max) revert Overflow();
        return uint96(value);
    }

    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize/address.code.length, which returns 0
        // for contracts in construction, since the code is only stored at the end
        // of the constructor execution.

        return account.code.length > 0;
    }

    bytes private constant token0Selector =
        abi.encodeWithSelector(IUniswapV2Pair.token0.selector);
    bytes private constant token1Selector =
        abi.encodeWithSelector(IUniswapV2Pair.token1.selector);

    function pairTokens(address pair) internal view returns (address token0, address token1) {
        // Do not check if pair is not a contract to avoid warning in txn log
        if (!isContract(pair)) return (address(0), address(0)); 

        return (tokenLookup(pair, token0Selector), tokenLookup(pair, token1Selector));
    }

    function tokenLookup(address pair, bytes memory selector)
        private
        view
        returns (address)
    {
        (bool success, bytes memory data) = pair.staticcall(selector);

        if (success && data.length >= 32) {
            return abi.decode(data, (address));
        }
        
        return address(0);
    }

}

library EverRiseLib {
    function swapTokensForEth(
        IUniswapV2Router02 uniswapV2Router,
        uint256 tokenAmount
    ) external {
        address tokenAddress = address(this);
        // generate the uniswap pair path of token -> weth
        address[] memory path = new address[](2);
        path[0] = tokenAddress;
        path[1] = uniswapV2Router.WETH();

        // make the swap
        uniswapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens(
            tokenAmount,
            0, // accept any amount of ETH
            path,
            tokenAddress, // The contract
            block.timestamp
        );
    }

    function swapETHForTokensNoFee(
        IUniswapV2Router02 uniswapV2Router,
        address toAddress, 
        uint256 amount
    ) external {
        // generate the uniswap pair path of token -> weth
        address[] memory path = new address[](2);
        path[0] = uniswapV2Router.WETH();
        path[1] = address(this);

        // make the swap
        uniswapV2Router.swapExactETHForTokens{
            value: amount
        }(
            0, // accept any amount of Tokens
            path,
            toAddress, // The contract
            block.timestamp
        );
    }
}
// File: EverRise-v3/Interfaces/IEverDrop.sol

interface IEverDrop {
    function mirgateV1V2Holder(address holder, uint96 amount) external returns(bool);
    function mirgateV2Staker(address toAddress, uint96 rewards, uint96 depositTokens, uint8 numOfMonths, uint48 depositTime, uint96 withdrawnAmount) external returns(uint256 nftId);
}
// File: EverRise-v3/Interfaces/IERC20-Token.sol

interface IERC20 {
    event Transfer(address indexed from, address indexed to, uint256 value);
    event Approval(address indexed owner, address indexed spender, uint256 value);
    function totalSupply() external view returns (uint256);
    function balanceOf(address account) external view returns (uint256);
    function transfer(address recipient, uint256 amount) external returns (bool);
    function allowance(address owner, address spender) external view returns (uint256);
    function approve(address spender, uint256 amount) external returns (bool);
    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
    function transferFromWithPermit(address sender, address recipient, uint256 amount, uint256 deadline, uint8 v, bytes32 r, bytes32 s) external returns (bool);
}

interface IERC20Metadata is IERC20 {
    function name() external view returns (string memory);
    function symbol() external view returns (string memory);
    function decimals() external view returns (uint8);
}
// File: EverRise-v3/Abstract/EverRiseWallet.sol

abstract contract EverRiseWallet is Context, IERC2612, IEverRiseWallet, IERC20Metadata {
    using EverRiseAddressNumberLib for address;

    // keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)");
    bytes32 public constant PERMIT_TYPEHASH = 0x6e71edae12b1b97f4d1f60370fef10105fa2faae0126114a169c64845d6126c9;
    // keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)");
    bytes32 public constant DOMAIN_TYPEHASH = 0x8b73c3c69bb8fe3d512ecc4cf759cc79239f7b179b0ffacaa9a75d522b39400f;

    mapping (address => ApprovalChecks) internal _approvals;
    mapping (address => mapping (address => Allowance)) public allowances;
    //Lock related fields
    mapping(address => address) private _userUnlocks;

    function _walletLock(address fromAddress) internal view {
        if (_isWalletLocked(fromAddress)) revert WalletLocked();
    }

    modifier walletLock(address fromAddress) {
        _walletLock(fromAddress);
        _;
    }
    
    function _isWalletLocked(address fromAddress) internal view returns (bool) {
        return _approvals[fromAddress].unlockTimestamp > block.timestamp;
    }

    function DOMAIN_SEPARATOR() public view returns (bytes32) {
        // Unique DOMAIN_SEPARATOR per user nbased on their current token check
        uint32 tokenCheck = _approvals[_msgSender()].tokenCheck;

        return keccak256(
            abi.encode(
                DOMAIN_TYPEHASH,
                keccak256(bytes(name())),
                keccak256(abi.encodePacked(tokenCheck)),
                block.chainid,
                address(this)
            )
        );
    }

    function name() public virtual view returns (string memory);

    function nonces(address owner) external view returns (uint256) {
        return _approvals[owner].nonce;
    }

    /**
     * @dev Grants or revokes permission to `operator` to transfer the caller's tokens, according to `approved`,
     *
     * Emits an {ApprovalForAll} event.
     *
     * Requirements:
     *
     * - `operator` cannot be the caller.
     */
    function _setApprovalForAll(address owner, address operator, bool approved) internal {
        if (operator == address(0)) revert NotZeroAddress();

        Allowance storage _allowance = allowances[owner][operator];
        ApprovalChecks storage _approval = _approvals[owner];
        if (approved) {

            uint16 autoRevokeNftHours = _approval.autoRevokeNftHours;
            uint48 timestamp = autoRevokeNftHours == 0 ? 
                type(uint48).max : // Don't timeout approval
                uint48(block.timestamp) + autoRevokeNftHours * 1 hours; // Timeout after user chosen period

            _allowance.nftCheck = _approval.nftCheck;
            _allowance.timestamp = timestamp;
            _allowance.nftApproval = 1;
        } else {
            unchecked {
                // nftCheck gets incremented, so set one behind approval
                _allowance.nftCheck = _approval.nftCheck - 1;
            }
            _allowance.nftApproval = 0;
        }
    }

    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) public {
        if (spender == address(0)) revert NotZeroAddress();
        if (deadline < block.timestamp) revert Expired();

        ApprovalChecks storage _approval = _approvals[owner];
        uint64 nonce = _approval.nonce;

        bytes32 digest = keccak256(
            abi.encodePacked(
                "\x19\x01",
                DOMAIN_SEPARATOR(),
                keccak256(
                    abi.encode(
                        PERMIT_TYPEHASH,
                        owner,
                        spender,
                        value,
                        nonce,
                        deadline
                    )
                )
            )
        );

        unchecked {
            // Nonces can wrap
            ++nonce;
        }

        _approval.nonce = nonce;
        
        if (v < 27) {
            v += 27;
        } else if (v > 30) {
            digest = keccak256(abi.encodePacked("\x19Ethereum Signed Message:\n32", digest));
        }

        address recoveredAddress = ecrecover(digest, v, r, s);
        if (recoveredAddress == address(0) || recoveredAddress != owner) revert InvalidSignature();
        
        _approve(owner, spender, value, true);
    }

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

    function _approve(
        address owner,
        address spender,
        uint256 amount,
        bool extend
    ) internal returns (bool) {
        if (owner == address(0)) revert NotZeroAddress();
        if (spender == address(0)) revert NotZeroAddress();

        if (amount > type(uint128).max) amount = type(uint128).max;

        ApprovalChecks storage _approval = _approvals[owner];
        Allowance storage _allowance = allowances[owner][spender];

        _allowance.tokenAmount = uint128(amount);
        _allowance.tokenCheck = _approval.tokenCheck;
        if (extend) {
            uint48 autoRevokeTokenHours = _approval.autoRevokeTokenHours;
            // Time extention approval
            _allowance.timestamp = autoRevokeTokenHours == 0 ? 
                type(uint48).max : // Don't timeout approval
                uint48(block.timestamp) + autoRevokeTokenHours * 1 hours; // Timeout after user chosen period
        }

        _allowance.tokenApproval = 1;
        
        emit Approval(owner, spender, amount);
        return true;
    }

    function allowance(address owner, address spender) public view returns (uint256) {
        uint32 tokenCheck = _approvals[owner].tokenCheck;
        Allowance storage allowanceSettings = allowances[owner][spender];

        if (tokenCheck != allowanceSettings.tokenCheck ||
            block.timestamp > allowanceSettings.timestamp ||
            allowanceSettings.tokenApproval != 1)
        {
            return 0;
        }

        return allowanceSettings.tokenAmount;
    }

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

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

        _transfer(sender, recipient, amount);

        uint256 _allowance = allowance(sender, _msgSender());
        if (amount > _allowance) revert AmountLargerThanAllowance();
        unchecked {
            _allowance -= amount;
        }
        _approve(sender, _msgSender(), _allowance, false);
        return true;
    }

    function transferFromWithPermit(
        address sender,
        address recipient,
        uint256 amount,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external returns (bool) {
        permit(sender, _msgSender(), amount, deadline, v, r, s);

        return transferFrom(sender, recipient, amount);
    }

    function lockTokensAndNfts(address altAccount, uint48 length) external walletLock(_msgSender()) {
        if (altAccount == address(0)) revert NotZeroAddress();
        if (length / 1 days > 10 * 365 days) revert LockTimeTooLong();

        _approvals[_msgSender()].unlockTimestamp = uint48(block.timestamp) + length;
        _userUnlocks[_msgSender()] = altAccount;

        emit LockWallet(_msgSender(), altAccount, length);
    }

    function extendLockTokensAndNfts(uint48 length) external {
        if (length / 1 days > 10 * 365 days) revert LockTimeTooLong();
        uint48 currentLock = _approvals[_msgSender()].unlockTimestamp;

        if (currentLock < block.timestamp) revert Unlocked();

        uint48 newLock = uint48(block.timestamp) + length;
        if (currentLock > newLock) revert LockTimeTooShort();
        _approvals[_msgSender()].unlockTimestamp = newLock;

        emit LockWalletExtend(_msgSender(), length);
    }

    function unlockTokensAndNfts(address actualAccount) external {
        if (_userUnlocks[actualAccount] != _msgSender()) revert CallerNotApproved();
        uint48 currentLock = _approvals[_msgSender()].unlockTimestamp;

        if (currentLock < block.timestamp) revert Unlocked();

        _approvals[_msgSender()].unlockTimestamp = 1;
    }

    function revokeApprovals(bool tokens, bool nfts) external {
        address account = _msgSender();
        ApprovalChecks storage _approval = _approvals[account];

        unchecked {
            // Nonces can wrap
            if (nfts) {
                ++_approval.nftCheck;
            }
            if (tokens) {
                ++_approval.tokenCheck;
            }
        }

        emit RevokeAllApprovals(account, tokens, nfts);
    }

    function setAutoTimeout(uint16 tokensHrs, uint16 nftsHrs) external {
        address account = _msgSender();
        ApprovalChecks storage _approval = _approvals[account];

        _approval.autoRevokeNftHours = nftsHrs;
        _approval.autoRevokeTokenHours = tokensHrs;

        emit SetApprovalAutoTimeout(account, tokensHrs, nftsHrs);
    }

    /**
     * @dev Returns true if `operator` is approved to transfer ``account``'s tokens.
     *
     * See {setApprovalForAll}.
     */
    function _isApprovedForAll(address account, address operator) internal view returns (bool) {
        uint32 nftCheck = _approvals[account].nftCheck;
        Allowance storage _allowance = allowances[account][operator];

        if (nftCheck != _allowance.nftCheck ||
            block.timestamp > _allowance.timestamp ||
            _allowance.nftApproval != 1)
        {
            return false;
        }

        return true;
    }

    function _transfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual;
}
// File: EverRise-v3/Interfaces/IEverRise.sol

interface IEverRise is IERC20Metadata {
    function totalBuyVolume() external view returns (uint256);
    function totalSellVolume() external view returns (uint256);
    function holders() external view returns (uint256);
    function uniswapV2Pair() external view returns (address);
    function transferStake(address fromAddress, address toAddress, uint96 amountToTransfer) external;
    function isWalletLocked(address fromAddress) external view returns (bool);
    function setApprovalForAll(address fromAddress, address operator, bool approved) external;
    function isApprovedForAll(address account, address operator) external view returns (bool);
    function isExcludedFromFee(address account) external view returns (bool);

    function approvals(address account) external view returns (ApprovalChecks memory);
}
// File: EverRise-v3/Abstract/EverRiseConfigurable.sol

abstract contract EverRiseConfigurable is EverRiseRoles, EverRiseWallet, IEverRise {
    using EverRiseAddressNumberLib for uint256;

    event BuyBackEnabledUpdated(bool enabled);
    event SwapEnabledUpdated(bool enabled);

    event ExcludeFromFeeUpdated(address account);
    event IncludeInFeeUpdated(address account);

    event LiquidityFeeUpdated(uint256 newValue);
    event TransactionCapUpdated(uint256 newValue);
    event MinStakeSizeUpdated(uint256 newValue);

    event BusinessDevelopmentDivisorUpdated(uint256 newValue);
    event MinTokensBeforeSwapUpdated(uint256 newValue);
    event BuybackMinAvailabilityUpdated(uint256 newValue);
    event MinBuybackAmountUpdated(uint256 newvalue);
    event MaxBuybackAmountUpdated(uint256 newvalue);

    event BuybackUpperLimitUpdated(uint256 newValue);
    event BuyBackTriggerTokenLimitUpdated(uint256 newValue);
    event BuybackBlocksUpdated(uint256 newValue);

    event BridgeVaultAddressUpdated(address indexed contractAddress);
    event BurnAddressUpdated(address indexed deadAddress);
    event OffChainBalanceExcluded(bool enable);
    event RouterAddressUpdated(address indexed newAddress);
    event BusinessDevelopmentAddressUpdated(address indexed newAddress);
    event StakingAddressUpdated(address indexed contractAddress);

    event LiquidityLocked(bool isLocked);
    event AutoBurnEnabled(bool enabled);
    event BurnableTokensZeroed();

    event ExchangeHotWalletAdded(address indexed exchangeHotWallet);
    event ExchangeHotWalletRemoved(address indexed exchangeHotWallet);
    event BuyBackTriggered();
    event BuyBackCrossChainTriggered();

    address payable public businessDevelopmentAddress =
        payable(0x24D8DAbebD6c0d5CcC88EC40D95Bf8eB64F0CF9E); // Business Development Address
    address public everBridgeVault;
    address public burnAddress = 0x000000000000000000000000000000000000dEaD;
    
    mapping (address => bool) internal _isExcludedFromFee;
    mapping (address => bool) internal _exchangeHotWallet;

    uint8 public constant decimals = 18;
    // Golden supply
    uint96 internal immutable _totalSupply = uint96(7_1_618_033_988 * 10**decimals);

    function totalSupply() external view returns (uint256) {
        return _totalSupply;
    }

    // Fee and max txn are set by setTradingEnabled
    // to allow upgrading balances to arrange their wallets
    // and stake their assets before trading start

    uint256 public totalBuyVolume;
    uint256 public totalSellVolume;
    uint256 public transactionCap;
    uint96 public liquidityFee = 6;

    uint256 public businessDevelopmentDivisor = 2;

    uint96 internal _minimumTokensBeforeSwap = uint96(5 * 10**6 * 10**decimals);
    uint256 internal _buyBackUpperLimit = 10 * 10**18;
    uint256 internal _buyBackTriggerTokenLimit = 1 * 10**6 * 10**decimals;
    uint256 internal _buyBackMinAvailability = 1 * 10**18; //1 BNB

    uint256 internal _nextBuybackAmount;
    uint256 internal _latestBuybackBlock;
    uint256 internal _numberOfBlocks = 1000;
    uint256 internal _minBuybackAmount = 1 * 10**18 / (10**1);
    uint256 internal _maxBuybackAmount = 1 * 10**18;

    // Booleans are more expensive than uint256 or any type that takes up a full
    // word because each write operation emits an extra SLOAD to first read the
    // slot's contents, replace the bits taken up by the boolean, and then write
    // back. This is the compiler's defense against contract upgrades and
    // pointer aliasing, and it cannot be disabled.
    uint256 constant _FALSE = 1;
    uint256 constant _TRUE = 2;

    // The values being non-zero value makes deployment a bit more expensive,
    // but in exchange the refund on every call to modifiers will be lower in
    // amount. Since refunds are capped to a percentage of the total
    // transaction's gas, it is best to keep them low in cases like this one, to
    // increase the likelihood of the full refund coming into effect.
    uint256 internal _inSwap = _FALSE;
    uint256 internal _swapEnabled = _FALSE;
    uint256 internal _buyBackEnabled = _FALSE;
    uint256 internal _liquidityLocked = _TRUE;
    uint256 internal _offchainBalanceExcluded = _FALSE;
    uint256 internal _autoBurn = _FALSE;
    uint256 internal _burnableTokens = 1;

    IUniswapV2Router02 public uniswapV2Router;
    address public uniswapV2Pair;
    
    InftEverRise public stakeToken;

    function swapEnabled() external view returns (bool) {
        return _swapEnabled == _TRUE;
    }
    function offchainBalanceExcluded() external view returns (bool) {
        return _offchainBalanceExcluded == _TRUE;
    }
    function buyBackEnabled() external view returns (bool) {
        return _buyBackEnabled == _TRUE;
    }
    function liquidityLocked() external view returns (bool) {
        return _liquidityLocked == _TRUE;
    }
    function autoBurn() external view returns (bool) {
        return _autoBurn == _TRUE;
    }

    function setBurnableTokensZero() external onlyController(Role.Liquidity)  {
        // set to 1 rather than zero to save on gas
        _burnableTokens = 1;
        emit BurnableTokensZeroed();
    }
    function setBurnAddress(address _burnAddress) external onlyController(Role.Liquidity)  {
        // May be bridgable burn (so only send to actual burn address on one chain)
        burnAddress = _burnAddress;
        emit BurnAddressUpdated(_burnAddress);
    }

    function setOffchainBalanceExcluded(bool _enabled) external onlyOwner {
        _offchainBalanceExcluded = _enabled ? _TRUE : _FALSE;
        emit OffChainBalanceExcluded(_enabled);
    }

    function setLiquidityLock(bool _enabled) public onlyController(Role.Liquidity) {
        _liquidityLocked = _enabled ? _TRUE : _FALSE;
        emit LiquidityLocked(_enabled);
    }

    function setAutoBurn(bool _enabled) external onlyController(Role.Liquidity) {
        _autoBurn = _enabled ? _TRUE : _FALSE;
        emit AutoBurnEnabled(_enabled);
    }

    function excludeFromFee(address account) public onlyController(Role.Fees) {
        if (_isExcludedFromFee[account]) revert InvalidAddress();
        
        _isExcludedFromFee[account] = true;
        emit ExcludeFromFeeUpdated(account);
    }

    function addExchangeHotWallet(address account) external onlyController(Role.Exchanges) {
        _exchangeHotWallet[account] = true;
        emit ExchangeHotWalletAdded(account);
    }

    function removeExchangeHotWallet(address account) external onlyController(Role.Exchanges) {
        _exchangeHotWallet[account] = false;
        emit ExchangeHotWalletRemoved(account);
    }

    function isExchangeHotWallet(address account) public view returns(bool) {
        return _exchangeHotWallet[account];
    }

    function includeInFee(address account) external onlyController(Role.Fees) {
        if (!_isExcludedFromFee[account]) revert InvalidAddress();

        _isExcludedFromFee[account] = false;
        emit IncludeInFeeUpdated(account);
    }

    function setTransactionCap(uint256 txAmount) external onlyController(Role.Limits) {
        // Never under 0.001%
        if (txAmount < _totalSupply / 100_000) revert AmountOutOfRange();

        transactionCap = txAmount;
        emit TransactionCapUpdated(txAmount);
    }

    function setNumberOfBlocksForBuyback(uint256 value) external onlyController(Role.BuyBack){
        if (value < 100 || value > 1_000_000) revert AmountOutOfRange();
        _numberOfBlocks = value;
        emit BuybackBlocksUpdated(value);
    }

    function setBusinessDevelopmentDivisor(uint256 divisor) external onlyController(Role.Liquidity) {
        if (divisor > liquidityFee) revert AmountOutOfRange();

        businessDevelopmentDivisor = divisor;
        emit BusinessDevelopmentDivisorUpdated(divisor);
    }

    function setNumTokensSellToAddToLiquidity(uint96 minimumTokensBeforeSwap)
        external
        onlyController(Role.Liquidity)
    {
        if (minimumTokensBeforeSwap > 1_000_000_000) revert AmountOutOfRange();

        _minimumTokensBeforeSwap = uint96(minimumTokensBeforeSwap * (10**uint256(decimals)));
        emit MinTokensBeforeSwapUpdated(minimumTokensBeforeSwap);
    }

    function setBuybackUpperLimit(uint256 buyBackLimit, uint256 numOfDecimals)
        external
        onlyController(Role.BuyBack)
    {
        // Catch typos, if decimals are pre-added
        if (buyBackLimit > 1_000_000_000) revert AmountOutOfRange();

        _buyBackUpperLimit = buyBackLimit * (10**18) / (10**numOfDecimals);
        emit BuybackUpperLimitUpdated(_buyBackUpperLimit);
    }

    function setMinBuybackAmount(uint256 minAmount, uint256 numOfDecimals)
        external
        onlyController(Role.BuyBack)
    {
        // Catch typos, if decimals are pre-added
        if (minAmount > 1_000) revert AmountOutOfRange();

        _minBuybackAmount = minAmount * (10**18) / (10**numOfDecimals);
        emit MinBuybackAmountUpdated(minAmount);
    }

    function setMaxBuybackAmountUpdated(uint256 maxAmount, uint256 numOfDecimals)
        external
        onlyController(Role.BuyBack)
    {
        // Catch typos, if decimals are pre-added
        if (maxAmount > 1_000_000) revert AmountOutOfRange();

        _maxBuybackAmount = maxAmount * (10**18) / (10**numOfDecimals);
        emit MaxBuybackAmountUpdated(maxAmount);
    }

    function setBuybackTriggerTokenLimit(uint256 buyBackTriggerLimit)
        external
        onlyController(Role.BuyBack)
    {
        if (buyBackTriggerLimit > 100_000_000) revert AmountOutOfRange();
        
        _buyBackTriggerTokenLimit = buyBackTriggerLimit * (10**uint256(decimals));
        emit BuyBackTriggerTokenLimitUpdated(_buyBackTriggerTokenLimit);
    }

    function setBuybackMinAvailability(uint256 amount, uint256 numOfDecimals)
        external
        onlyController(Role.BuyBack)
    {
        if (amount > 100_000) revert AmountOutOfRange();

        _buyBackMinAvailability = amount * (10**18) / (10**numOfDecimals);
        emit BuybackMinAvailabilityUpdated(_buyBackMinAvailability);
    }

    function setBuyBackEnabled(bool _enabled) external onlyController(Role.BuyBack) {
        _buyBackEnabled = _enabled ? _TRUE : _FALSE;
        emit BuyBackEnabledUpdated(_enabled);
    }

    function setBusinessDevelopmentAddress(address newAddress)
        external
        onlyController(Role.Liquidity)
    {
        if (newAddress == address(0)) revert NotZeroAddress();

        businessDevelopmentAddress = payable(newAddress);
        emit BusinessDevelopmentAddressUpdated(newAddress);
    }

    function setEverBridgeVaultAddress(address contractAddress)
        external
        onlyOwner
    {
        
        excludeFromFee(contractAddress);
        
        everBridgeVault = contractAddress;
        emit BridgeVaultAddressUpdated(contractAddress);
    }

    function setStakingAddress(address contractAddress) external onlyOwner {
        stakeToken = InftEverRise(contractAddress);

        excludeFromFee(contractAddress);

        emit StakingAddressUpdated(contractAddress);
    }

    function setRouterAddress(address newAddress) external onlyController(Role.Liquidity) {
        if (newAddress == address(0)) revert NotZeroAddress();

        IUniswapV2Router02 _uniswapV2Router = IUniswapV2Router02(newAddress); 
        uniswapV2Pair = IUniswapV2Factory(_uniswapV2Router.factory()).getPair(
            address(this),
            _uniswapV2Router.WETH()
        );

        uniswapV2Router = _uniswapV2Router;
        emit RouterAddressUpdated(newAddress);
    }

    function isExcludedFromFee(address account) external view returns (bool) {
        return _isExcludedFromFee[account];
    }

    function setSwapEnabled(bool _enabled) external onlyOwner {
        _swapEnabled = _enabled ? _TRUE : _FALSE;
        emit SwapEnabledUpdated(_enabled);
    }

    function hasTokenStarted() public view returns (bool) {
        return transactionCap > 0;
    }

    function setLiquidityFeePercent(uint96 liquidityFeeRate) external onlyController(Role.Liquidity) {
        if (liquidityFeeRate > 10) revert AmountOutOfRange();
        liquidityFee = liquidityFeeRate;
        emit LiquidityFeeUpdated(liquidityFeeRate);
    }
}
// File: EverRise-v3/EverRise.sol

// Copyright (c) 2022 EverRise Pte Ltd. All rights reserved.
// EverRise licenses this file to you under the MIT license.
/*
 The EverRise token is the keystone in the EverRise Ecosytem of dApps
 and the overaching key that unlocks multi-blockchain unification via
 the EverBridge.

 On EverRise token txns 6% buyback and business development fees are collected
 * 4% for token Buyback from the market, 
     with bought back tokens directly distributed as ve-staking rewards
 * 2% for Business Development (Development, Sustainability and Marketing)

  ________                              _______   __
 /        |                            /       \ /  |
 $$$$$$$$/__     __  ______    ______  $$$$$$$  |$$/   _______   ______  v3.14159265
 $$ |__  /  \   /  |/      \  /      \ $$ |__$$ |/  | /       | /      \
 $$    | $$  \ /$$//$$$$$$  |/$$$$$$  |$$    $$< $$ |/$$$$$$$/ /$$$$$$  |
 $$$$$/   $$  /$$/ $$    $$ |$$ |  $$/ $$$$$$$  |$$ |$$      \ $$    $$ |
 $$ |_____ $$ $$/  $$$$$$$$/ $$ |      $$ |  $$ |$$ | $$$$$$  |$$$$$$$$/
 $$       | $$$/   $$       |$$ |      $$ |  $$ |$$ |/     $$/ $$       |
 $$$$$$$$/   $/     $$$$$$$/ $$/       $$/   $$/ $$/ $$$$$$$/   $$$$$$$/

 Learn more about EverRise and the EverRise Ecosystem of dApps and
 how our utilities and partners can help protect your investors
 and help your project grow: https://www.everrise.com
*/

// 2^96 is 79 * 10**10 * 10**18
struct TransferDetails {
    uint96 balance0;
    address to;

    uint96 balance1;
    address origin;

    uint32 blockNumber;
}

contract EverRise is EverRiseConfigurable, IEverDrop {
    using EverRiseAddressNumberLib for address;
    using EverRiseAddressNumberLib for uint256;

    event BuybackTokensWithETH(uint256 amountIn, uint256 amountOut);
    event ConvertTokensForETH(uint256 amountIn, uint256 amountOut);

    event TokenStarted();
    event RewardStakers(uint256 amount);
    event AutoBurn(uint256 amount);

    event StakingIncreased(address indexed from, uint256 amount, uint8 numberOfmonths);
    event StakingDecreased(address indexed from, uint256 amount);

    event RiseBridgedIn(address indexed contractAddress, address indexed to, uint256 amount);
    event RiseBridgedOut(address indexed contractAddress, address indexed from, uint256 amount);
    event NftBridgedIn(address indexed contractAddress, address indexed operator, address indexed to, uint256 id, uint256 value);
    event NftBridgedOut(address indexed contractAddress, address indexed operator, address indexed from, uint256 id, uint256 value);
    event TransferExternalTokens(address indexed tokenAddress, address indexed to, uint256 count);

    // Holder count
    uint256 private _holders;
    // Balance and locked (staked) balance
    mapping (address => uint96) private _tOwned;
    mapping (address => uint96) private _amountLocked;

    // Tracking for protections against sandwich trades
    // and rogue LP pairs
    mapping (address => uint256) private _lastTrade;
    TransferDetails private _lastTransfer;

    string public constant symbol = "RISE";
    function name() public override (EverRiseWallet, IERC20Metadata) pure returns (string memory) {
        return "EverRise";
    }

    modifier lockTheSwap() {
        require(_inSwap != _TRUE);
        _inSwap = _TRUE;
        _;
        // By storing the original value once again, a refund is triggered (see
        // https://eips.ethereum.org/EIPS/eip-2200)
        _inSwap = _FALSE;
    }

    constructor(address routerAddress) {
        if (routerAddress == address(0)) revert NotZeroAddress();

        IUniswapV2Router02 _uniswapV2Router = IUniswapV2Router02(routerAddress);
        // IUniswapV2Router02 _uniswapV2Router = IUniswapV2Router02(0x10ED43C718714eb63d5aA57B78B54704E256024E); //Pancakeswap router mainnet - BSC
        // IUniswapV2Router02 _uniswapV2Router = IUniswapV2Router02(0xD99D1c33F9fC3444f8101754aBC46c52416550D1); //Testnet
        // IUniswapV2Router02 _uniswapV2Router = IUniswapV2Router02(0xa5e0829caced8ffdd4de3c43696c57f7d7a678ff); //Quickswap V2 router mainnet - Polygon
        // IUniswapV2Router02 _uniswapV2Router = IUniswapV2Router02(0x1b02dA8Cb0d097eB8D57A175b88c7D8b47997506); //Sushiswap router mainnet - Polygon
        // IUniswapV2Router02 _uniswapV2Router = IUniswapV2Router02(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D); //Uniswap V2 router mainnet - ETH
        uniswapV2Pair = IUniswapV2Factory(_uniswapV2Router.factory())
            .createPair(address(this), _uniswapV2Router.WETH());

        uniswapV2Router = _uniswapV2Router;
  
        _isExcludedFromFee[owner] = true;
        _isExcludedFromFee[address(this)] = true;

        // Put all tokens in contract so we can airdrop
        _tOwned[address(this)] = _totalSupply;
        emit Transfer(address(0), address(this), _totalSupply);

        _holders = 1;
    }

    // Function to receive ETH when msg.data is be empty
    receive() external payable {}

    // Balances
    function isWalletLocked(address fromAddress) override (IEverRise) external view returns (bool) {
        return _isWalletLocked(fromAddress);
    }

    function holders() external view returns (uint256) {
        return _holders;
    }

    function getAmountLocked(address account) external view returns (uint256) {
        return _amountLocked[account];
    }

    function _balanceOf(address account) private view returns (uint256) {
        return _tOwned[account];
    }

    function bridgeVaultLockedBalance() external view returns (uint256) {
        return _balanceOf(everBridgeVault);
    }

    function balanceOf(address account) external view override returns (uint256) {
        // Bridge vault balances are on other chains
        if (account == everBridgeVault && _offchainBalanceExcluded == _TRUE) return 0;

        uint256 balance = _balanceOf(account);
        if (_inSwap != _TRUE &&
            _lastTransfer.blockNumber == uint32(block.number) &&
            account.isContract() &&
            !_isExcludedFromFee[account]
        ) {
            // Balance being checked is same address as last to in _transfer
            // check if likely same txn and a Liquidity Add
            _validateIfLiquidityChange(account, uint112(balance));
        }

        return balance;
    }

    // Transfers

    function approvals(address account) external view returns (ApprovalChecks memory) {
        return _approvals[account]; 
    }
    
    function _transfer(
        address from,
        address to,
        uint256 amount
    ) internal override walletLock(from) {
        if (from == address(0) || to == address(0)) revert NotZeroAddress();
        if (amount == 0) revert AmountMustBeGreaterThanZero();
        if (amount > (_balanceOf(from) - _amountLocked[from])) revert AmountLargerThanUnlockedAmount();

        bool isIgnoredAddress = _isExcludedFromFee[from] || _isExcludedFromFee[to];

        bool notInSwap = _inSwap != _TRUE;
        bool hasStarted = hasTokenStarted();
        address pair = uniswapV2Pair;
        bool isSell = to == pair;
        bool isBuy = from == pair;
        if (!isIgnoredAddress) {
            if (to == address(this)) revert NotContractAddress();
            if (amount > transactionCap) revert TransferTooLarge();
            if (!hasStarted) revert TokenNotStarted();
            if (notInSwap) {
                // Disallow multiple same source trades in same block
                if ((isSell || isBuy) && _lastTrade[tx.origin] == block.number) {
                    revert SandwichTradesAreDisallowed();
                }

                _lastTrade[tx.origin] = block.number;

                // Following block is for the contract to convert the tokens to ETH and do the buy back
                if (isSell && _swapEnabled == _TRUE) {
                    uint96 swapTokens = _minimumTokensBeforeSwap;
                    if (_balanceOf(address(this)) > swapTokens) {
                        // Greater than to always leave at least 1 token in contract
                        // reducing gas from switching from 0 to not-zero and not tracking
                        // token in holder count changes.
                        _convertTokens(swapTokens);
                    }

                    if (_buyback()) {
                        emit BuyBackTriggered();
                    }
                }
            }
        }

        if (hasStarted) {
            if (isBuy) {
                totalBuyVolume += amount;
            } else if (isSell) { 
                totalSellVolume += amount;
                if (amount > _buyBackTriggerTokenLimit) {
                    // Start at 1% of balance
                    uint256 amountToAdd = address(this).balance / 100;
                    uint256 maxToAdd = _buyBackUpperLimit / 100;
                    // Don't add more than the 1% of the upper limit
                    if (amountToAdd > maxToAdd) amountToAdd = maxToAdd;
                    // Add to next buyback
                    _nextBuybackAmount += amountToAdd;
                }
            }
        }

        // If any account belongs to _isExcludedFromFee account then remove the fee
        bool takeFee = true;
        if (isIgnoredAddress || isExchangeHotWallet(to)) {
            takeFee = false;
        }
        
        // For safety Liquidity Adds should only be done by an owner, 
        // and transfers to and from EverRise Ecosystem contracts
        // are not considered LP adds
        if (notInSwap) {
            if (isIgnoredAddress) {
                // Just set blocknumber to 1 to clear, to save gas on changing back
                _lastTransfer.blockNumber = 1;
            } else {
                // Not in a swap during a LP add, so record the transfer details
                _recordPotentialLiquidityChangeTransaction(to);
            }
        }

        _tokenTransfer(from, to, uint96(amount), takeFee);
    }

    function _tokenTransfer(
        address sender,
        address recipient,
        uint96 amount,
        bool takeFee
    ) private {
        uint96 fromAfter = _tOwned[sender] - amount;
        _tOwned[sender] = fromAfter;

        uint96 tLiquidity = takeFee ? amount * liquidityFee / (10**2) : 0;
        uint96 tTransferAmount = amount - tLiquidity;

        uint96 toBefore = _tOwned[recipient]; 
        _tOwned[recipient] = toBefore + tTransferAmount;

        if (tLiquidity > 0) {
            // Skip writing to save gas if unchanged
            _tOwned[address(this)] += tLiquidity;
        }

        _trackHolders(fromAfter, toBefore);
        if (sender == everBridgeVault) {
            emit RiseBridgedIn(everBridgeVault, recipient, amount);
        } else if (recipient == everBridgeVault) {
            emit RiseBridgedOut(everBridgeVault, sender, amount);
        }

        emit Transfer(sender, recipient, tTransferAmount);
    }

    function _lockedTokenTransfer(
        address sender,
        address recipient,
        uint96 amount
    ) private {
        // Do the locked token transfer
        _decreaseLockedAmount(sender, amount, false);
        uint96 fromAfter = _tOwned[sender] - amount;
        _tOwned[sender] = fromAfter;
        
        uint96 toBefore = _tOwned[recipient]; 
        _tOwned[recipient] = toBefore + amount;
        _increaseLockedAmount(recipient, amount);

        _trackHolders(fromAfter, toBefore);

        emit Transfer(sender, recipient, amount);
    }

    function _trackHolders(uint96 fromAfter, uint96 toBefore) private {
        uint256 startHolderCount = _holders;
        uint256 holderCount = startHolderCount;
        
        if (fromAfter == 0) --holderCount;
        if (toBefore == 0) ++holderCount;

        if (startHolderCount != holderCount) {
            // Skip writing to save gas if unchanged
            _holders = holderCount;
        }
    }

    // Buyback
    function crossChainBuyback() external onlyController(Role.CrossChainBuyback) {
        if (_buyback()) {
            emit BuyBackCrossChainTriggered();
        }

        // Is autoburn on?
        if (_autoBurn == _TRUE) {
            uint96 swapTokens = _minimumTokensBeforeSwap;
            // Have we collected enough tokens to burn?
            if (_burnableTokens > swapTokens) {
                unchecked {
                    // Just confirmed is valid above
                    _burnableTokens -= swapTokens;
                }
                // Burn the tokens
                _tokenTransfer(uniswapV2Pair, burnAddress, swapTokens, false);
                // Reset LP balances
                IUniswapV2Pair(uniswapV2Pair).sync();

                emit AutoBurn(swapTokens);
            }
        }
    }

    function _buyback() private returns (bool boughtBack) {
        if (_buyBackEnabled == _TRUE) {
            uint256 balance = address(this).balance;
            if (balance > _buyBackMinAvailability &&
                block.number > _latestBuybackBlock + _numberOfBlocks 
            ) {
                // Max of 10% of balance
                balance /= 10;
                uint256 buybackAmount = _nextBuybackAmount;
                if (buybackAmount > _maxBuybackAmount) {
                    buybackAmount = _maxBuybackAmount;
                }
                if (buybackAmount > balance) {
                    // Don't try to buyback more than is available.
                    buybackAmount = balance;
                }

                if (buybackAmount > 0) {
                    boughtBack = _buyBackTokens(buybackAmount);
                }
            }
        }
    }

    function _buyBackTokens(uint256 amount) private lockTheSwap returns (bool boughtBack) {
        _nextBuybackAmount = _minBuybackAmount; // reset the next buyback amount, set non-zero to save on future gas

        if (amount > 0) {
            uint256 tokensBefore = _balanceOf(address(stakeToken));
            EverRiseLib.swapETHForTokensNoFee(uniswapV2Router, address(stakeToken), amount);
            // Don't trust the return value; calculate it ourselves
            uint256 tokensReceived = _balanceOf(address(stakeToken)) - tokensBefore;

            emit BuybackTokensWithETH(amount, tokensReceived);
            _latestBuybackBlock = block.number;
            //Distribute the rewards to the staking pool
            _distributeStakingRewards(tokensReceived);

            boughtBack = true;
        }
    }
    
    // Non-EverSwap LP conversion
    function _convertTokens(uint256 tokenAmount) private lockTheSwap {
        uint256 initialETHBalance = address(this).balance;

        _approve(address(this), address(uniswapV2Router), tokenAmount, true);
        // Mark the tokens as available to burn
        _burnableTokens += uint96(tokenAmount);

        EverRiseLib.swapTokensForEth(uniswapV2Router, tokenAmount);

        uint256 transferredETHBalance = address(this).balance - initialETHBalance;
        emit ConvertTokensForETH(tokenAmount, transferredETHBalance);

        // Send split to Business Development address
        transferredETHBalance = transferredETHBalance * businessDevelopmentDivisor / liquidityFee;
        sendEthViaCall(businessDevelopmentAddress, transferredETHBalance);
    }

    // Staking

    function _distributeStakingRewards(uint256 amount) private {
        if (amount > 0) {
            stakeToken.createRewards(amount);

            emit RewardStakers(amount);
        }
    }
    
    function transferStake(address fromAddress, address toAddress, uint96 amountToTransfer) external walletLock(fromAddress) {
        if (_msgSender() != address(stakeToken)) revert NotStakeContractRequesting();

        _lockedTokenTransfer(fromAddress, toAddress, amountToTransfer);
    }

    function enterStaking(uint96 amount, uint8 numOfMonths) external payable walletLock(_msgSender()) {
        address staker = _msgSender();
        if (msg.value < stakeToken.stakeCreateCost()) revert NotEnoughToCoverStakeFee();

        uint32 nftId = stakeToken.enterStaking(staker, amount, numOfMonths);

        _lockAndAddStaker(staker, amount, numOfMonths, nftId);
    }

    function increaseStake(uint256 nftId, uint96 amount)
        external walletLock(_msgSender())
    {
        address staker = _msgSender();
        _increaseLockedAmount(staker, amount);

        uint8 numOfMonths;
        uint96 original;
        (, original, numOfMonths) = stakeToken.increaseStake(staker, nftId, amount);

        emit StakingDecreased(staker, original);
        emit StakingIncreased(staker, original + amount, numOfMonths);
    }

    function _increaseLockedAmount(address staker, uint96 amount) private {
        uint96 lockedAmount = _amountLocked[staker] + amount;
        if (lockedAmount > _balanceOf(staker)) revert AmountLargerThanUnlockedAmount();
        _amountLocked[staker] = lockedAmount;
        
        emit Transfer(staker, staker, amount);
    }

    function _decreaseLockedAmount(address staker, uint96 amount, bool emitEvent) private {
        _amountLocked[staker] -= amount;
        if (emitEvent) {
            emit StakingDecreased(staker, amount);
            emit Transfer(staker, staker, amount);
        }
    }

    function leaveStaking(uint256 nftId, bool overrideNotClaimed) external walletLock(_msgSender()) {
        address staker = _msgSender();

        uint96 amount = stakeToken.leaveStaking(staker, nftId, overrideNotClaimed);
        _decreaseLockedAmount(staker, amount, true);
        stakeToken.removeStaker(staker, nftId);
    }

    function earlyWithdraw(uint256 nftId, uint96 amount) external walletLock(_msgSender()) {
        address staker = _msgSender();

        (uint32 newNftId, uint96 penaltyAmount) = stakeToken.earlyWithdraw(staker, nftId, amount);
        _decreaseLockedAmount(staker, amount, true);
        
        if (penaltyAmount > 0) {
            _tokenTransfer(staker, address(stakeToken), penaltyAmount, false);
            _distributeStakingRewards(penaltyAmount);
        }

        stakeToken.reissueStakeNft(staker, nftId, newNftId);
    }

    function withdraw(uint256 nftId, uint96 amount, bool overrideNotClaimed) external walletLock(_msgSender()) {
        address staker = _msgSender();

        (uint32 newNftId) = stakeToken.withdraw(staker, nftId, amount, overrideNotClaimed);
        if (amount > 0) {
            _decreaseLockedAmount(staker, amount, true);
        }
        if (nftId != newNftId && newNftId != 0) {
            stakeToken.reissueStakeNft(staker, nftId, newNftId);
        }
    }

    function setApprovalForAll(address fromAddress, address operator, bool approved) external {
        if (_msgSender() != address(stakeToken)) revert NotStakeContractRequesting();

        _setApprovalForAll(fromAddress, operator, approved);
    }

    function isApprovedForAll(address account, address operator) external view returns (bool) {
        if (_msgSender() != address(stakeToken)) revert NotStakeContractRequesting();

        return _isApprovedForAll(account, operator);
    }
    
    // Nft bridging
    function approveNFTAndTokens(address bridgeAddress, uint256 nftId, uint256 tokenAmount) external {
        if (!roles[Role.NftBridge][bridgeAddress]) revert NotContractAddress();

        stakeToken.approve(_msgSender(), bridgeAddress, nftId);
        _approve(_msgSender(), bridgeAddress, tokenAmount, true);
    }

    function bridgeStakeNftOut(address fromAddress, uint256 nftId) external onlyController(Role.NftBridge) {
        if (stakeToken.getApproved(nftId) != _msgSender() && !stakeToken.isApprovedForAll(_msgSender(), fromAddress)) {
            revert CallerNotApproved();
        }
        
        _walletLock(fromAddress);

        uint96 amount = stakeToken.bridgeStakeNftOut(fromAddress, nftId);
        _decreaseLockedAmount(fromAddress, amount, true);
        // Send tokens to vault
        _tokenTransfer(fromAddress, everBridgeVault, amount, false);

        stakeToken.removeStaker(fromAddress, nftId);
        emit NftBridgedOut(address(this), everBridgeVault, fromAddress, nftId, amount);
    }

    function bridgeStakeNftIn(address toAddress, uint96 depositTokens, uint8 numOfMonths, uint48 depositTime, uint96 withdrawnAmount, bool achievementClaimed) external onlyController(Role.NftBridge) returns (uint256 nftId)
    {
        nftId = stakeToken.bridgeOrAirdropStakeNftIn(toAddress, depositTokens, numOfMonths, depositTime, withdrawnAmount, 0, achievementClaimed);

        uint96 amount = depositTokens - withdrawnAmount;
        //Send the tokens from Vault
        _tokenTransfer(everBridgeVault, toAddress, amount, false);

        _lockAndAddStaker(toAddress, amount, numOfMonths, nftId);

        emit NftBridgedIn(address(this), everBridgeVault, toAddress, nftId, amount);
    }

    function _lockAndAddStaker(address toAddress, uint96 amount, uint8 numOfMonths, uint256 nftId) private {
        _increaseLockedAmount(toAddress, amount);
        stakeToken.addStaker(toAddress, nftId);

        emit StakingIncreased(toAddress, amount, numOfMonths);
    }

    // Liquidity

    function _recordPotentialLiquidityChangeTransaction(address to) private {
        uint96 balance0 = uint96(_balanceOf(to));
        (address token0, address token1) = to.pairTokens();
        if (token1 == address(this)) {
            // Switch token so token1 is always other side of pair
            token1 = token0;
        } 
        
        if (token1 == address(0)) {
            // Not LP pair, just set blocknumber to 1 to clear, to save gas on changing back
            _lastTransfer.blockNumber = 1;
            return;
        }
        
        uint96 balance1 = uint96(IERC20(token1).balanceOf(to));

        _lastTransfer = TransferDetails({
            balance0: balance0,
            to: to,
            balance1: balance1,
            origin: tx.origin,
            blockNumber: uint32(block.number)
        });
    }

    // account must be recorded in _transfer and same block
    function _validateIfLiquidityChange(address account, uint112 balance0) private view {
        if (_lastTransfer.origin != tx.origin ||
            account != _lastTransfer.to) {
            // Not same txn, or not LP addETH
            return;
        }

        // Check if LP change using the data recorded in _transfer
        // May be same transaction as _transfer
        (address token0, address token1) = account.pairTokens();
        // Not LP pair
        if (token1 == address(0)) return;
        bool switchTokens;
        if (token1 == address(this)) {
            // Switch token so token1 is always other side of pair
            token1 = token0;
            switchTokens = true;
        } else if (token0 != address(this)) {
            // Not LP for this token
            return;
        }

        uint256 balance1 = IERC20(token1).balanceOf(account);
        // Test to see if this tx is part of a liquidity add
        if (balance0 > _lastTransfer.balance0 &&
            balance1 > _lastTransfer.balance1) {
            // Both pair balances have increased, this is a Liquidty Add
            // Will block addETH and where other token address sorts higher
            revert LiquidityAddOwnerOnly();
        }
    }

    // Admin

    function upgradeComplete() external onlyOwner {
        // Can only be called before start
        if (hasTokenStarted()) revert TokenAlreadyStarted();

        // We will keep one token always in contract
        // so we don't need to track it in holder changes
        _tokenTransfer(address(this), _msgSender(), _tOwned[address(this)] - 1, false);

        _buyBackEnabled = _TRUE;
        _swapEnabled = _TRUE;
        transactionCap = _totalSupply / 1000; // Max txn 0.1% of supply

        emit TokenStarted();
    }

    function sendEthViaCall(address payable to, uint256 amount) private {
        (bool sent, ) = to.call{value: amount}("");
        if (!sent) revert FailedEthSend();
    }

    function transferBalance(uint256 amount) external onlyOwner {
        sendEthViaCall(_msgSender(), amount);
    }

    function transferExternalTokens(address tokenAddress, address to, uint256 amount) external onlyOwner {
        if (tokenAddress == address(0)) revert NotZeroAddress();

        transferTokens(tokenAddress, to, amount);
    }

    function transferTokens(address tokenAddress, address to, uint256 amount) private {
        IERC20(tokenAddress).transfer(to, amount);

        emit TransferExternalTokens(tokenAddress, to, amount);
    }

    function mirgateV2Staker(address toAddress, uint96 rewards,uint96 depositTokens, uint8 numOfMonths, uint48 depositTime, uint96 withdrawnAmount) external onlyController(Role.Upgrader) returns(uint256 nftId)
    {
        nftId = stakeToken.bridgeOrAirdropStakeNftIn(toAddress, depositTokens, numOfMonths, depositTime, withdrawnAmount, rewards, false);

        uint96 amount = depositTokens - withdrawnAmount;

        _tokenTransfer(address(this), toAddress, amount, false);
        if (rewards > 0) {
            _tokenTransfer(address(this), address(stakeToken), rewards, false);
        }
        
        _lockAndAddStaker(toAddress, amount, numOfMonths, nftId);
    }

    function mirgateV1V2Holder(address holder, uint96 amount) external onlyController(Role.Upgrader) returns(bool) {
        _tokenTransfer(address(this), holder, amount, false);
        return true;
    }
}

// File: contracts/interfaces/IUniswapV2Pair.sol

pragma solidity >=0.5.0;

interface IUniswapV2Pair {
    event Approval(address indexed owner, address indexed spender, uint value);
    event Transfer(address indexed from, address indexed to, uint value);

    function name() external pure returns (string memory);
    function symbol() external pure returns (string memory);
    function decimals() external pure returns (uint8);
    function totalSupply() external view returns (uint);
    function balanceOf(address owner) external view returns (uint);
    function allowance(address owner, address spender) external view returns (uint);

    function approve(address spender, uint value) external returns (bool);
    function transfer(address to, uint value) external returns (bool);
    function transferFrom(address from, address to, uint value) external returns (bool);

    function DOMAIN_SEPARATOR() external view returns (bytes32);
    function PERMIT_TYPEHASH() external pure returns (bytes32);
    function nonces(address owner) external view returns (uint);

    function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external;

    event Mint(address indexed sender, uint amount0, uint amount1);
    event Burn(address indexed sender, uint amount0, uint amount1, address indexed to);
    event Swap(
        address indexed sender,
        uint amount0In,
        uint amount1In,
        uint amount0Out,
        uint amount1Out,
        address indexed to
    );
    event Sync(uint112 reserve0, uint112 reserve1);

    function MINIMUM_LIQUIDITY() external pure returns (uint);
    function factory() external view returns (address);
    function token0() external view returns (address);
    function token1() external view returns (address);
    function getReserves() external view returns (uint112 reserve0, uint112 reserve1, uint32 blockTimestampLast);
    function price0CumulativeLast() external view returns (uint);
    function price1CumulativeLast() external view returns (uint);
    function kLast() external view returns (uint);

    function mint(address to) external returns (uint liquidity);
    function burn(address to) external returns (uint amount0, uint amount1);
    function swap(uint amount0Out, uint amount1Out, address to, bytes calldata data) external;
    function skim(address to) external;
    function sync() external;

    function initialize(address, address) external;
}

// File: contracts/interfaces/IUniswapV2ERC20.sol

pragma solidity >=0.5.0;

interface IUniswapV2ERC20 {
    event Approval(address indexed owner, address indexed spender, uint value);
    event Transfer(address indexed from, address indexed to, uint value);

    function name() external pure returns (string memory);
    function symbol() external pure returns (string memory);
    function decimals() external pure returns (uint8);
    function totalSupply() external view returns (uint);
    function balanceOf(address owner) external view returns (uint);
    function allowance(address owner, address spender) external view returns (uint);

    function approve(address spender, uint value) external returns (bool);
    function transfer(address to, uint value) external returns (bool);
    function transferFrom(address from, address to, uint value) external returns (bool);

    function DOMAIN_SEPARATOR() external view returns (bytes32);
    function PERMIT_TYPEHASH() external pure returns (bytes32);
    function nonces(address owner) external view returns (uint);

    function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external;
}

// File: contracts/libraries/SafeMath.sol

pragma solidity =0.5.16;

// a library for performing overflow-safe math, courtesy of DappHub (https://github.com/dapphub/ds-math)

library SafeMath {
    function add(uint x, uint y) internal pure returns (uint z) {
        require((z = x + y) >= x, 'ds-math-add-overflow');
    }

    function sub(uint x, uint y) internal pure returns (uint z) {
        require((z = x - y) <= x, 'ds-math-sub-underflow');
    }

    function mul(uint x, uint y) internal pure returns (uint z) {
        require(y == 0 || (z = x * y) / y == x, 'ds-math-mul-overflow');
    }
}

// File: contracts/UniswapV2ERC20.sol

pragma solidity =0.5.16;



contract UniswapV2ERC20 is IUniswapV2ERC20 {
    using SafeMath for uint;

    string public constant name = 'Uniswap V2';
    string public constant symbol = 'UNI-V2';
    uint8 public constant decimals = 18;
    uint  public totalSupply;
    mapping(address => uint) public balanceOf;
    mapping(address => mapping(address => uint)) public allowance;

    bytes32 public DOMAIN_SEPARATOR;
    // keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)");
    bytes32 public constant PERMIT_TYPEHASH = 0x6e71edae12b1b97f4d1f60370fef10105fa2faae0126114a169c64845d6126c9;
    mapping(address => uint) public nonces;

    event Approval(address indexed owner, address indexed spender, uint value);
    event Transfer(address indexed from, address indexed to, uint value);

    constructor() public {
        uint chainId;
        assembly {
            chainId := chainid
        }
        DOMAIN_SEPARATOR = keccak256(
            abi.encode(
                keccak256('EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)'),
                keccak256(bytes(name)),
                keccak256(bytes('1')),
                chainId,
                address(this)
            )
        );
    }

    function _mint(address to, uint value) internal {
        totalSupply = totalSupply.add(value);
        balanceOf[to] = balanceOf[to].add(value);
        emit Transfer(address(0), to, value);
    }

    function _burn(address from, uint value) internal {
        balanceOf[from] = balanceOf[from].sub(value);
        totalSupply = totalSupply.sub(value);
        emit Transfer(from, address(0), value);
    }

    function _approve(address owner, address spender, uint value) private {
        allowance[owner][spender] = value;
        emit Approval(owner, spender, value);
    }

    function _transfer(address from, address to, uint value) private {
        balanceOf[from] = balanceOf[from].sub(value);
        balanceOf[to] = balanceOf[to].add(value);
        emit Transfer(from, to, value);
    }

    function approve(address spender, uint value) external returns (bool) {
        _approve(msg.sender, spender, value);
        return true;
    }

    function transfer(address to, uint value) external returns (bool) {
        _transfer(msg.sender, to, value);
        return true;
    }

    function transferFrom(address from, address to, uint value) external returns (bool) {
        if (allowance[from][msg.sender] != uint(-1)) {
            allowance[from][msg.sender] = allowance[from][msg.sender].sub(value);
        }
        _transfer(from, to, value);
        return true;
    }

    function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external {
        require(deadline >= block.timestamp, 'UniswapV2: EXPIRED');
        bytes32 digest = keccak256(
            abi.encodePacked(
                '\x19\x01',
                DOMAIN_SEPARATOR,
                keccak256(abi.encode(PERMIT_TYPEHASH, owner, spender, value, nonces[owner]++, deadline))
            )
        );
        address recoveredAddress = ecrecover(digest, v, r, s);
        require(recoveredAddress != address(0) && recoveredAddress == owner, 'UniswapV2: INVALID_SIGNATURE');
        _approve(owner, spender, value);
    }
}

// File: contracts/libraries/Math.sol

pragma solidity =0.5.16;

// a library for performing various math operations

library Math {
    function min(uint x, uint y) internal pure returns (uint z) {
        z = x < y ? x : y;
    }

    // babylonian method (https://en.wikipedia.org/wiki/Methods_of_computing_square_roots#Babylonian_method)
    function sqrt(uint y) internal pure returns (uint z) {
        if (y > 3) {
            z = y;
            uint x = y / 2 + 1;
            while (x < z) {
                z = x;
                x = (y / x + x) / 2;
            }
        } else if (y != 0) {
            z = 1;
        }
    }
}

// File: contracts/libraries/UQ112x112.sol

pragma solidity =0.5.16;

// a library for handling binary fixed point numbers (https://en.wikipedia.org/wiki/Q_(number_format))

// range: [0, 2**112 - 1]
// resolution: 1 / 2**112

library UQ112x112 {
    uint224 constant Q112 = 2**112;

    // encode a uint112 as a UQ112x112
    function encode(uint112 y) internal pure returns (uint224 z) {
        z = uint224(y) * Q112; // never overflows
    }

    // divide a UQ112x112 by a uint112, returning a UQ112x112
    function uqdiv(uint224 x, uint112 y) internal pure returns (uint224 z) {
        z = x / uint224(y);
    }
}

// File: contracts/interfaces/IERC20.sol

pragma solidity >=0.5.0;

interface IERC20 {
    event Approval(address indexed owner, address indexed spender, uint value);
    event Transfer(address indexed from, address indexed to, uint value);

    function name() external view returns (string memory);
    function symbol() external view returns (string memory);
    function decimals() external view returns (uint8);
    function totalSupply() external view returns (uint);
    function balanceOf(address owner) external view returns (uint);
    function allowance(address owner, address spender) external view returns (uint);

    function approve(address spender, uint value) external returns (bool);
    function transfer(address to, uint value) external returns (bool);
    function transferFrom(address from, address to, uint value) external returns (bool);
}

// File: contracts/interfaces/IUniswapV2Factory.sol

pragma solidity >=0.5.0;

interface IUniswapV2Factory {
    event PairCreated(address indexed token0, address indexed token1, address pair, uint);

    function feeTo() external view returns (address);
    function feeToSetter() external view returns (address);

    function getPair(address tokenA, address tokenB) external view returns (address pair);
    function allPairs(uint) external view returns (address pair);
    function allPairsLength() external view returns (uint);

    function createPair(address tokenA, address tokenB) external returns (address pair);

    function setFeeTo(address) external;
    function setFeeToSetter(address) external;
}

// File: contracts/interfaces/IUniswapV2Callee.sol

pragma solidity >=0.5.0;

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

// File: contracts/UniswapV2Pair.sol

pragma solidity =0.5.16;








contract UniswapV2Pair is IUniswapV2Pair, UniswapV2ERC20 {
    using SafeMath  for uint;
    using UQ112x112 for uint224;

    uint public constant MINIMUM_LIQUIDITY = 10**3;
    bytes4 private constant SELECTOR = bytes4(keccak256(bytes('transfer(address,uint256)')));

    address public factory;
    address public token0;
    address public token1;

    uint112 private reserve0;           // uses single storage slot, accessible via getReserves
    uint112 private reserve1;           // uses single storage slot, accessible via getReserves
    uint32  private blockTimestampLast; // uses single storage slot, accessible via getReserves

    uint public price0CumulativeLast;
    uint public price1CumulativeLast;
    uint public kLast; // reserve0 * reserve1, as of immediately after the most recent liquidity event

    uint private unlocked = 1;
    modifier lock() {
        require(unlocked == 1, 'UniswapV2: LOCKED');
        unlocked = 0;
        _;
        unlocked = 1;
    }

    function getReserves() public view returns (uint112 _reserve0, uint112 _reserve1, uint32 _blockTimestampLast) {
        _reserve0 = reserve0;
        _reserve1 = reserve1;
        _blockTimestampLast = blockTimestampLast;
    }

    function _safeTransfer(address token, address to, uint value) private {
        (bool success, bytes memory data) = token.call(abi.encodeWithSelector(SELECTOR, to, value));
        require(success && (data.length == 0 || abi.decode(data, (bool))), 'UniswapV2: TRANSFER_FAILED');
    }

    event Mint(address indexed sender, uint amount0, uint amount1);
    event Burn(address indexed sender, uint amount0, uint amount1, address indexed to);
    event Swap(
        address indexed sender,
        uint amount0In,
        uint amount1In,
        uint amount0Out,
        uint amount1Out,
        address indexed to
    );
    event Sync(uint112 reserve0, uint112 reserve1);

    constructor() public {
        factory = msg.sender;
    }

    // called once by the factory at time of deployment
    function initialize(address _token0, address _token1) external {
        require(msg.sender == factory, 'UniswapV2: FORBIDDEN'); // sufficient check
        token0 = _token0;
        token1 = _token1;
    }

    // update reserves and, on the first call per block, price accumulators
    function _update(uint balance0, uint balance1, uint112 _reserve0, uint112 _reserve1) private {
        require(balance0 <= uint112(-1) && balance1 <= uint112(-1), 'UniswapV2: OVERFLOW');
        uint32 blockTimestamp = uint32(block.timestamp % 2**32);
        uint32 timeElapsed = blockTimestamp - blockTimestampLast; // overflow is desired
        if (timeElapsed > 0 && _reserve0 != 0 && _reserve1 != 0) {
            // * never overflows, and + overflow is desired
            price0CumulativeLast += uint(UQ112x112.encode(_reserve1).uqdiv(_reserve0)) * timeElapsed;
            price1CumulativeLast += uint(UQ112x112.encode(_reserve0).uqdiv(_reserve1)) * timeElapsed;
        }
        reserve0 = uint112(balance0);
        reserve1 = uint112(balance1);
        blockTimestampLast = blockTimestamp;
        emit Sync(reserve0, reserve1);
    }

    // if fee is on, mint liquidity equivalent to 1/6th of the growth in sqrt(k)
    function _mintFee(uint112 _reserve0, uint112 _reserve1) private returns (bool feeOn) {
        address feeTo = IUniswapV2Factory(factory).feeTo();
        feeOn = feeTo != address(0);
        uint _kLast = kLast; // gas savings
        if (feeOn) {
            if (_kLast != 0) {
                uint rootK = Math.sqrt(uint(_reserve0).mul(_reserve1));
                uint rootKLast = Math.sqrt(_kLast);
                if (rootK > rootKLast) {
                    uint numerator = totalSupply.mul(rootK.sub(rootKLast));
                    uint denominator = rootK.mul(5).add(rootKLast);
                    uint liquidity = numerator / denominator;
                    if (liquidity > 0) _mint(feeTo, liquidity);
                }
            }
        } else if (_kLast != 0) {
            kLast = 0;
        }
    }

    // this low-level function should be called from a contract which performs important safety checks
    function mint(address to) external lock returns (uint liquidity) {
        (uint112 _reserve0, uint112 _reserve1,) = getReserves(); // gas savings
        uint balance0 = IERC20(token0).balanceOf(address(this));
        uint balance1 = IERC20(token1).balanceOf(address(this));
        uint amount0 = balance0.sub(_reserve0);
        uint amount1 = balance1.sub(_reserve1);

        bool feeOn = _mintFee(_reserve0, _reserve1);
        uint _totalSupply = totalSupply; // gas savings, must be defined here since totalSupply can update in _mintFee
        if (_totalSupply == 0) {
            liquidity = Math.sqrt(amount0.mul(amount1)).sub(MINIMUM_LIQUIDITY);
           _mint(address(0), MINIMUM_LIQUIDITY); // permanently lock the first MINIMUM_LIQUIDITY tokens
        } else {
            liquidity = Math.min(amount0.mul(_totalSupply) / _reserve0, amount1.mul(_totalSupply) / _reserve1);
        }
        require(liquidity > 0, 'UniswapV2: INSUFFICIENT_LIQUIDITY_MINTED');
        _mint(to, liquidity);

        _update(balance0, balance1, _reserve0, _reserve1);
        if (feeOn) kLast = uint(reserve0).mul(reserve1); // reserve0 and reserve1 are up-to-date
        emit Mint(msg.sender, amount0, amount1);
    }

    // this low-level function should be called from a contract which performs important safety checks
    function burn(address to) external lock returns (uint amount0, uint amount1) {
        (uint112 _reserve0, uint112 _reserve1,) = getReserves(); // gas savings
        address _token0 = token0;                                // gas savings
        address _token1 = token1;                                // gas savings
        uint balance0 = IERC20(_token0).balanceOf(address(this));
        uint balance1 = IERC20(_token1).balanceOf(address(this));
        uint liquidity = balanceOf[address(this)];

        bool feeOn = _mintFee(_reserve0, _reserve1);
        uint _totalSupply = totalSupply; // gas savings, must be defined here since totalSupply can update in _mintFee
        amount0 = liquidity.mul(balance0) / _totalSupply; // using balances ensures pro-rata distribution
        amount1 = liquidity.mul(balance1) / _totalSupply; // using balances ensures pro-rata distribution
        require(amount0 > 0 && amount1 > 0, 'UniswapV2: INSUFFICIENT_LIQUIDITY_BURNED');
        _burn(address(this), liquidity);
        _safeTransfer(_token0, to, amount0);
        _safeTransfer(_token1, to, amount1);
        balance0 = IERC20(_token0).balanceOf(address(this));
        balance1 = IERC20(_token1).balanceOf(address(this));

        _update(balance0, balance1, _reserve0, _reserve1);
        if (feeOn) kLast = uint(reserve0).mul(reserve1); // reserve0 and reserve1 are up-to-date
        emit Burn(msg.sender, amount0, amount1, to);
    }

    // this low-level function should be called from a contract which performs important safety checks
    function swap(uint amount0Out, uint amount1Out, address to, bytes calldata data) external lock {
        require(amount0Out > 0 || amount1Out > 0, 'UniswapV2: INSUFFICIENT_OUTPUT_AMOUNT');
        (uint112 _reserve0, uint112 _reserve1,) = getReserves(); // gas savings
        require(amount0Out < _reserve0 && amount1Out < _reserve1, 'UniswapV2: INSUFFICIENT_LIQUIDITY');

        uint balance0;
        uint balance1;
        { // scope for _token{0,1}, avoids stack too deep errors
        address _token0 = token0;
        address _token1 = token1;
        require(to != _token0 && to != _token1, 'UniswapV2: INVALID_TO');
        if (amount0Out > 0) _safeTransfer(_token0, to, amount0Out); // optimistically transfer tokens
        if (amount1Out > 0) _safeTransfer(_token1, to, amount1Out); // optimistically transfer tokens
        if (data.length > 0) IUniswapV2Callee(to).uniswapV2Call(msg.sender, amount0Out, amount1Out, data);
        balance0 = IERC20(_token0).balanceOf(address(this));
        balance1 = IERC20(_token1).balanceOf(address(this));
        }
        uint amount0In = balance0 > _reserve0 - amount0Out ? balance0 - (_reserve0 - amount0Out) : 0;
        uint amount1In = balance1 > _reserve1 - amount1Out ? balance1 - (_reserve1 - amount1Out) : 0;
        require(amount0In > 0 || amount1In > 0, 'UniswapV2: INSUFFICIENT_INPUT_AMOUNT');
        { // scope for reserve{0,1}Adjusted, avoids stack too deep errors
        uint balance0Adjusted = balance0.mul(1000).sub(amount0In.mul(3));
        uint balance1Adjusted = balance1.mul(1000).sub(amount1In.mul(3));
        require(balance0Adjusted.mul(balance1Adjusted) >= uint(_reserve0).mul(_reserve1).mul(1000**2), 'UniswapV2: K');
        }

        _update(balance0, balance1, _reserve0, _reserve1);
        emit Swap(msg.sender, amount0In, amount1In, amount0Out, amount1Out, to);
    }

    // force balances to match reserves
    function skim(address to) external lock {
        address _token0 = token0; // gas savings
        address _token1 = token1; // gas savings
        _safeTransfer(_token0, to, IERC20(_token0).balanceOf(address(this)).sub(reserve0));
        _safeTransfer(_token1, to, IERC20(_token1).balanceOf(address(this)).sub(reserve1));
    }

    // force reserves to match balances
    function sync() external lock {
        _update(IERC20(token0).balanceOf(address(this)), IERC20(token1).balanceOf(address(this)), reserve0, reserve1);
    }
}

pragma solidity =0.6.6;

interface IUniswapV2Factory {
    event PairCreated(address indexed token0, address indexed token1, address pair, uint);

    function feeTo() external view returns (address);
    function feeToSetter() external view returns (address);

    function getPair(address tokenA, address tokenB) external view returns (address pair);
    function allPairs(uint) external view returns (address pair);
    function allPairsLength() external view returns (uint);

    function createPair(address tokenA, address tokenB) external returns (address pair);

    function setFeeTo(address) external;
    function setFeeToSetter(address) external;
}

interface IUniswapV2Pair {
    event Approval(address indexed owner, address indexed spender, uint value);
    event Transfer(address indexed from, address indexed to, uint value);

    function name() external pure returns (string memory);
    function symbol() external pure returns (string memory);
    function decimals() external pure returns (uint8);
    function totalSupply() external view returns (uint);
    function balanceOf(address owner) external view returns (uint);
    function allowance(address owner, address spender) external view returns (uint);

    function approve(address spender, uint value) external returns (bool);
    function transfer(address to, uint value) external returns (bool);
    function transferFrom(address from, address to, uint value) external returns (bool);

    function DOMAIN_SEPARATOR() external view returns (bytes32);
    function PERMIT_TYPEHASH() external pure returns (bytes32);
    function nonces(address owner) external view returns (uint);

    function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external;

    event Mint(address indexed sender, uint amount0, uint amount1);
    event Burn(address indexed sender, uint amount0, uint amount1, address indexed to);
    event Swap(
        address indexed sender,
        uint amount0In,
        uint amount1In,
        uint amount0Out,
        uint amount1Out,
        address indexed to
    );
    event Sync(uint112 reserve0, uint112 reserve1);

    function MINIMUM_LIQUIDITY() external pure returns (uint);
    function factory() external view returns (address);
    function token0() external view returns (address);
    function token1() external view returns (address);
    function getReserves() external view returns (uint112 reserve0, uint112 reserve1, uint32 blockTimestampLast);
    function price0CumulativeLast() external view returns (uint);
    function price1CumulativeLast() external view returns (uint);
    function kLast() external view returns (uint);

    function mint(address to) external returns (uint liquidity);
    function burn(address to) external returns (uint amount0, uint amount1);
    function swap(uint amount0Out, uint amount1Out, address to, bytes calldata data) external;
    function skim(address to) external;
    function sync() external;

    function initialize(address, address) external;
}

interface IUniswapV2Router01 {
    function factory() external pure returns (address);
    function WETH() external pure returns (address);

    function addLiquidity(
        address tokenA,
        address tokenB,
        uint amountADesired,
        uint amountBDesired,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB, uint liquidity);
    function addLiquidityETH(
        address token,
        uint amountTokenDesired,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external payable returns (uint amountToken, uint amountETH, uint liquidity);
    function removeLiquidity(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB);
    function removeLiquidityETH(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external returns (uint amountToken, uint amountETH);
    function removeLiquidityWithPermit(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountA, uint amountB);
    function removeLiquidityETHWithPermit(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountToken, uint amountETH);
    function swapExactTokensForTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);
    function swapTokensForExactTokens(
        uint amountOut,
        uint amountInMax,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);
    function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline)
        external
        payable
        returns (uint[] memory amounts);
    function swapTokensForExactETH(uint amountOut, uint amountInMax, address[] calldata path, address to, uint deadline)
        external
        returns (uint[] memory amounts);
    function swapExactTokensForETH(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline)
        external
        returns (uint[] memory amounts);
    function swapETHForExactTokens(uint amountOut, address[] calldata path, address to, uint deadline)
        external
        payable
        returns (uint[] memory amounts);

    function quote(uint amountA, uint reserveA, uint reserveB) external pure returns (uint amountB);
    function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut) external pure returns (uint amountOut);
    function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut) external pure returns (uint amountIn);
    function getAmountsOut(uint amountIn, address[] calldata path) external view returns (uint[] memory amounts);
    function getAmountsIn(uint amountOut, address[] calldata path) external view returns (uint[] memory amounts);
}

interface IUniswapV2Router02 is IUniswapV2Router01 {
    function removeLiquidityETHSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external returns (uint amountETH);
    function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountETH);

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

interface IERC20 {
    event Approval(address indexed owner, address indexed spender, uint value);
    event Transfer(address indexed from, address indexed to, uint value);

    function name() external view returns (string memory);
    function symbol() external view returns (string memory);
    function decimals() external view returns (uint8);
    function totalSupply() external view returns (uint);
    function balanceOf(address owner) external view returns (uint);
    function allowance(address owner, address spender) external view returns (uint);

    function approve(address spender, uint value) external returns (bool);
    function transfer(address to, uint value) external returns (bool);
    function transferFrom(address from, address to, uint value) external returns (bool);
}

interface IWETH {
    function deposit() external payable;
    function transfer(address to, uint value) external returns (bool);
    function withdraw(uint) external;
}

contract UniswapV2Router02 is IUniswapV2Router02 {
    using SafeMath for uint;

    address public immutable override factory;
    address public immutable override WETH;

    modifier ensure(uint deadline) {
        require(deadline >= block.timestamp, 'UniswapV2Router: EXPIRED');
        _;
    }

    constructor(address _factory, address _WETH) public {
        factory = _factory;
        WETH = _WETH;
    }

    receive() external payable {
        assert(msg.sender == WETH); // only accept ETH via fallback from the WETH contract
    }

    // **** ADD LIQUIDITY ****
    function _addLiquidity(
        address tokenA,
        address tokenB,
        uint amountADesired,
        uint amountBDesired,
        uint amountAMin,
        uint amountBMin
    ) internal virtual returns (uint amountA, uint amountB) {
        // create the pair if it doesn't exist yet
        if (IUniswapV2Factory(factory).getPair(tokenA, tokenB) == address(0)) {
            IUniswapV2Factory(factory).createPair(tokenA, tokenB);
        }
        (uint reserveA, uint reserveB) = UniswapV2Library.getReserves(factory, tokenA, tokenB);
        if (reserveA == 0 && reserveB == 0) {
            (amountA, amountB) = (amountADesired, amountBDesired);
        } else {
            uint amountBOptimal = UniswapV2Library.quote(amountADesired, reserveA, reserveB);
            if (amountBOptimal <= amountBDesired) {
                require(amountBOptimal >= amountBMin, 'UniswapV2Router: INSUFFICIENT_B_AMOUNT');
                (amountA, amountB) = (amountADesired, amountBOptimal);
            } else {
                uint amountAOptimal = UniswapV2Library.quote(amountBDesired, reserveB, reserveA);
                assert(amountAOptimal <= amountADesired);
                require(amountAOptimal >= amountAMin, 'UniswapV2Router: INSUFFICIENT_A_AMOUNT');
                (amountA, amountB) = (amountAOptimal, amountBDesired);
            }
        }
    }
    function addLiquidity(
        address tokenA,
        address tokenB,
        uint amountADesired,
        uint amountBDesired,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external virtual override ensure(deadline) returns (uint amountA, uint amountB, uint liquidity) {
        (amountA, amountB) = _addLiquidity(tokenA, tokenB, amountADesired, amountBDesired, amountAMin, amountBMin);
        address pair = UniswapV2Library.pairFor(factory, tokenA, tokenB);
        TransferHelper.safeTransferFrom(tokenA, msg.sender, pair, amountA);
        TransferHelper.safeTransferFrom(tokenB, msg.sender, pair, amountB);
        liquidity = IUniswapV2Pair(pair).mint(to);
    }
    function addLiquidityETH(
        address token,
        uint amountTokenDesired,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external virtual override payable ensure(deadline) returns (uint amountToken, uint amountETH, uint liquidity) {
        (amountToken, amountETH) = _addLiquidity(
            token,
            WETH,
            amountTokenDesired,
            msg.value,
            amountTokenMin,
            amountETHMin
        );
        address pair = UniswapV2Library.pairFor(factory, token, WETH);
        TransferHelper.safeTransferFrom(token, msg.sender, pair, amountToken);
        IWETH(WETH).deposit{value: amountETH}();
        assert(IWETH(WETH).transfer(pair, amountETH));
        liquidity = IUniswapV2Pair(pair).mint(to);
        // refund dust eth, if any
        if (msg.value > amountETH) TransferHelper.safeTransferETH(msg.sender, msg.value - amountETH);
    }

    // **** REMOVE LIQUIDITY ****
    function removeLiquidity(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) public virtual override ensure(deadline) returns (uint amountA, uint amountB) {
        address pair = UniswapV2Library.pairFor(factory, tokenA, tokenB);
        IUniswapV2Pair(pair).transferFrom(msg.sender, pair, liquidity); // send liquidity to pair
        (uint amount0, uint amount1) = IUniswapV2Pair(pair).burn(to);
        (address token0,) = UniswapV2Library.sortTokens(tokenA, tokenB);
        (amountA, amountB) = tokenA == token0 ? (amount0, amount1) : (amount1, amount0);
        require(amountA >= amountAMin, 'UniswapV2Router: INSUFFICIENT_A_AMOUNT');
        require(amountB >= amountBMin, 'UniswapV2Router: INSUFFICIENT_B_AMOUNT');
    }
    function removeLiquidityETH(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) public virtual override ensure(deadline) returns (uint amountToken, uint amountETH) {
        (amountToken, amountETH) = removeLiquidity(
            token,
            WETH,
            liquidity,
            amountTokenMin,
            amountETHMin,
            address(this),
            deadline
        );
        TransferHelper.safeTransfer(token, to, amountToken);
        IWETH(WETH).withdraw(amountETH);
        TransferHelper.safeTransferETH(to, amountETH);
    }
    function removeLiquidityWithPermit(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external virtual override returns (uint amountA, uint amountB) {
        address pair = UniswapV2Library.pairFor(factory, tokenA, tokenB);
        uint value = approveMax ? uint(-1) : liquidity;
        IUniswapV2Pair(pair).permit(msg.sender, address(this), value, deadline, v, r, s);
        (amountA, amountB) = removeLiquidity(tokenA, tokenB, liquidity, amountAMin, amountBMin, to, deadline);
    }
    function removeLiquidityETHWithPermit(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external virtual override returns (uint amountToken, uint amountETH) {
        address pair = UniswapV2Library.pairFor(factory, token, WETH);
        uint value = approveMax ? uint(-1) : liquidity;
        IUniswapV2Pair(pair).permit(msg.sender, address(this), value, deadline, v, r, s);
        (amountToken, amountETH) = removeLiquidityETH(token, liquidity, amountTokenMin, amountETHMin, to, deadline);
    }

    // **** REMOVE LIQUIDITY (supporting fee-on-transfer tokens) ****
    function removeLiquidityETHSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) public virtual override ensure(deadline) returns (uint amountETH) {
        (, amountETH) = removeLiquidity(
            token,
            WETH,
            liquidity,
            amountTokenMin,
            amountETHMin,
            address(this),
            deadline
        );
        TransferHelper.safeTransfer(token, to, IERC20(token).balanceOf(address(this)));
        IWETH(WETH).withdraw(amountETH);
        TransferHelper.safeTransferETH(to, amountETH);
    }
    function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external virtual override returns (uint amountETH) {
        address pair = UniswapV2Library.pairFor(factory, token, WETH);
        uint value = approveMax ? uint(-1) : liquidity;
        IUniswapV2Pair(pair).permit(msg.sender, address(this), value, deadline, v, r, s);
        amountETH = removeLiquidityETHSupportingFeeOnTransferTokens(
            token, liquidity, amountTokenMin, amountETHMin, to, deadline
        );
    }

    // **** SWAP ****
    // requires the initial amount to have already been sent to the first pair
    function _swap(uint[] memory amounts, address[] memory path, address _to) internal virtual {
        for (uint i; i < path.length - 1; i++) {
            (address input, address output) = (path[i], path[i + 1]);
            (address token0,) = UniswapV2Library.sortTokens(input, output);
            uint amountOut = amounts[i + 1];
            (uint amount0Out, uint amount1Out) = input == token0 ? (uint(0), amountOut) : (amountOut, uint(0));
            address to = i < path.length - 2 ? UniswapV2Library.pairFor(factory, output, path[i + 2]) : _to;
            IUniswapV2Pair(UniswapV2Library.pairFor(factory, input, output)).swap(
                amount0Out, amount1Out, to, new bytes(0)
            );
        }
    }
    function swapExactTokensForTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external virtual override ensure(deadline) returns (uint[] memory amounts) {
        amounts = UniswapV2Library.getAmountsOut(factory, amountIn, path);
        require(amounts[amounts.length - 1] >= amountOutMin, 'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT');
        TransferHelper.safeTransferFrom(
            path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0]
        );
        _swap(amounts, path, to);
    }
    function swapTokensForExactTokens(
        uint amountOut,
        uint amountInMax,
        address[] calldata path,
        address to,
        uint deadline
    ) external virtual override ensure(deadline) returns (uint[] memory amounts) {
        amounts = UniswapV2Library.getAmountsIn(factory, amountOut, path);
        require(amounts[0] <= amountInMax, 'UniswapV2Router: EXCESSIVE_INPUT_AMOUNT');
        TransferHelper.safeTransferFrom(
            path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0]
        );
        _swap(amounts, path, to);
    }
    function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline)
        external
        virtual
        override
        payable
        ensure(deadline)
        returns (uint[] memory amounts)
    {
        require(path[0] == WETH, 'UniswapV2Router: INVALID_PATH');
        amounts = UniswapV2Library.getAmountsOut(factory, msg.value, path);
        require(amounts[amounts.length - 1] >= amountOutMin, 'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT');
        IWETH(WETH).deposit{value: amounts[0]}();
        assert(IWETH(WETH).transfer(UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0]));
        _swap(amounts, path, to);
    }
    function swapTokensForExactETH(uint amountOut, uint amountInMax, address[] calldata path, address to, uint deadline)
        external
        virtual
        override
        ensure(deadline)
        returns (uint[] memory amounts)
    {
        require(path[path.length - 1] == WETH, 'UniswapV2Router: INVALID_PATH');
        amounts = UniswapV2Library.getAmountsIn(factory, amountOut, path);
        require(amounts[0] <= amountInMax, 'UniswapV2Router: EXCESSIVE_INPUT_AMOUNT');
        TransferHelper.safeTransferFrom(
            path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0]
        );
        _swap(amounts, path, address(this));
        IWETH(WETH).withdraw(amounts[amounts.length - 1]);
        TransferHelper.safeTransferETH(to, amounts[amounts.length - 1]);
    }
    function swapExactTokensForETH(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline)
        external
        virtual
        override
        ensure(deadline)
        returns (uint[] memory amounts)
    {
        require(path[path.length - 1] == WETH, 'UniswapV2Router: INVALID_PATH');
        amounts = UniswapV2Library.getAmountsOut(factory, amountIn, path);
        require(amounts[amounts.length - 1] >= amountOutMin, 'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT');
        TransferHelper.safeTransferFrom(
            path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0]
        );
        _swap(amounts, path, address(this));
        IWETH(WETH).withdraw(amounts[amounts.length - 1]);
        TransferHelper.safeTransferETH(to, amounts[amounts.length - 1]);
    }
    function swapETHForExactTokens(uint amountOut, address[] calldata path, address to, uint deadline)
        external
        virtual
        override
        payable
        ensure(deadline)
        returns (uint[] memory amounts)
    {
        require(path[0] == WETH, 'UniswapV2Router: INVALID_PATH');
        amounts = UniswapV2Library.getAmountsIn(factory, amountOut, path);
        require(amounts[0] <= msg.value, 'UniswapV2Router: EXCESSIVE_INPUT_AMOUNT');
        IWETH(WETH).deposit{value: amounts[0]}();
        assert(IWETH(WETH).transfer(UniswapV2Library.pairFor(factory, path[0], path[1]), amounts[0]));
        _swap(amounts, path, to);
        // refund dust eth, if any
        if (msg.value > amounts[0]) TransferHelper.safeTransferETH(msg.sender, msg.value - amounts[0]);
    }

    // **** SWAP (supporting fee-on-transfer tokens) ****
    // requires the initial amount to have already been sent to the first pair
    function _swapSupportingFeeOnTransferTokens(address[] memory path, address _to) internal virtual {
        for (uint i; i < path.length - 1; i++) {
            (address input, address output) = (path[i], path[i + 1]);
            (address token0,) = UniswapV2Library.sortTokens(input, output);
            IUniswapV2Pair pair = IUniswapV2Pair(UniswapV2Library.pairFor(factory, input, output));
            uint amountInput;
            uint amountOutput;
            { // scope to avoid stack too deep errors
            (uint reserve0, uint reserve1,) = pair.getReserves();
            (uint reserveInput, uint reserveOutput) = input == token0 ? (reserve0, reserve1) : (reserve1, reserve0);
            amountInput = IERC20(input).balanceOf(address(pair)).sub(reserveInput);
            amountOutput = UniswapV2Library.getAmountOut(amountInput, reserveInput, reserveOutput);
            }
            (uint amount0Out, uint amount1Out) = input == token0 ? (uint(0), amountOutput) : (amountOutput, uint(0));
            address to = i < path.length - 2 ? UniswapV2Library.pairFor(factory, output, path[i + 2]) : _to;
            pair.swap(amount0Out, amount1Out, to, new bytes(0));
        }
    }
    function swapExactTokensForTokensSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external virtual override ensure(deadline) {
        TransferHelper.safeTransferFrom(
            path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amountIn
        );
        uint balanceBefore = IERC20(path[path.length - 1]).balanceOf(to);
        _swapSupportingFeeOnTransferTokens(path, to);
        require(
            IERC20(path[path.length - 1]).balanceOf(to).sub(balanceBefore) >= amountOutMin,
            'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT'
        );
    }
    function swapExactETHForTokensSupportingFeeOnTransferTokens(
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    )
        external
        virtual
        override
        payable
        ensure(deadline)
    {
        require(path[0] == WETH, 'UniswapV2Router: INVALID_PATH');
        uint amountIn = msg.value;
        IWETH(WETH).deposit{value: amountIn}();
        assert(IWETH(WETH).transfer(UniswapV2Library.pairFor(factory, path[0], path[1]), amountIn));
        uint balanceBefore = IERC20(path[path.length - 1]).balanceOf(to);
        _swapSupportingFeeOnTransferTokens(path, to);
        require(
            IERC20(path[path.length - 1]).balanceOf(to).sub(balanceBefore) >= amountOutMin,
            'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT'
        );
    }
    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    )
        external
        virtual
        override
        ensure(deadline)
    {
        require(path[path.length - 1] == WETH, 'UniswapV2Router: INVALID_PATH');
        TransferHelper.safeTransferFrom(
            path[0], msg.sender, UniswapV2Library.pairFor(factory, path[0], path[1]), amountIn
        );
        _swapSupportingFeeOnTransferTokens(path, address(this));
        uint amountOut = IERC20(WETH).balanceOf(address(this));
        require(amountOut >= amountOutMin, 'UniswapV2Router: INSUFFICIENT_OUTPUT_AMOUNT');
        IWETH(WETH).withdraw(amountOut);
        TransferHelper.safeTransferETH(to, amountOut);
    }

    // **** LIBRARY FUNCTIONS ****
    function quote(uint amountA, uint reserveA, uint reserveB) public pure virtual override returns (uint amountB) {
        return UniswapV2Library.quote(amountA, reserveA, reserveB);
    }

    function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut)
        public
        pure
        virtual
        override
        returns (uint amountOut)
    {
        return UniswapV2Library.getAmountOut(amountIn, reserveIn, reserveOut);
    }

    function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut)
        public
        pure
        virtual
        override
        returns (uint amountIn)
    {
        return UniswapV2Library.getAmountIn(amountOut, reserveIn, reserveOut);
    }

    function getAmountsOut(uint amountIn, address[] memory path)
        public
        view
        virtual
        override
        returns (uint[] memory amounts)
    {
        return UniswapV2Library.getAmountsOut(factory, amountIn, path);
    }

    function getAmountsIn(uint amountOut, address[] memory path)
        public
        view
        virtual
        override
        returns (uint[] memory amounts)
    {
        return UniswapV2Library.getAmountsIn(factory, amountOut, path);
    }
}

// a library for performing overflow-safe math, courtesy of DappHub (https://github.com/dapphub/ds-math)

library SafeMath {
    function add(uint x, uint y) internal pure returns (uint z) {
        require((z = x + y) >= x, 'ds-math-add-overflow');
    }

    function sub(uint x, uint y) internal pure returns (uint z) {
        require((z = x - y) <= x, 'ds-math-sub-underflow');
    }

    function mul(uint x, uint y) internal pure returns (uint z) {
        require(y == 0 || (z = x * y) / y == x, 'ds-math-mul-overflow');
    }
}

library UniswapV2Library {
    using SafeMath for uint;

    // returns sorted token addresses, used to handle return values from pairs sorted in this order
    function sortTokens(address tokenA, address tokenB) internal pure returns (address token0, address token1) {
        require(tokenA != tokenB, 'UniswapV2Library: IDENTICAL_ADDRESSES');
        (token0, token1) = tokenA < tokenB ? (tokenA, tokenB) : (tokenB, tokenA);
        require(token0 != address(0), 'UniswapV2Library: ZERO_ADDRESS');
    }

    // calculates the CREATE2 address for a pair without making any external calls
    function pairFor(address factory, address tokenA, address tokenB) internal pure returns (address pair) {
        (address token0, address token1) = sortTokens(tokenA, tokenB);
        pair = address(uint(keccak256(abi.encodePacked(
                hex'ff',
                factory,
                keccak256(abi.encodePacked(token0, token1)),
                hex'96e8ac4277198ff8b6f785478aa9a39f403cb768dd02cbee326c3e7da348845f' // init code hash
            ))));
    }

    // fetches and sorts the reserves for a pair
    function getReserves(address factory, address tokenA, address tokenB) internal view returns (uint reserveA, uint reserveB) {
        (address token0,) = sortTokens(tokenA, tokenB);
        (uint reserve0, uint reserve1,) = IUniswapV2Pair(pairFor(factory, tokenA, tokenB)).getReserves();
        (reserveA, reserveB) = tokenA == token0 ? (reserve0, reserve1) : (reserve1, reserve0);
    }

    // given some amount of an asset and pair reserves, returns an equivalent amount of the other asset
    function quote(uint amountA, uint reserveA, uint reserveB) internal pure returns (uint amountB) {
        require(amountA > 0, 'UniswapV2Library: INSUFFICIENT_AMOUNT');
        require(reserveA > 0 && reserveB > 0, 'UniswapV2Library: INSUFFICIENT_LIQUIDITY');
        amountB = amountA.mul(reserveB) / reserveA;
    }

    // given an input amount of an asset and pair reserves, returns the maximum output amount of the other asset
    function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut) internal pure returns (uint amountOut) {
        require(amountIn > 0, 'UniswapV2Library: INSUFFICIENT_INPUT_AMOUNT');
        require(reserveIn > 0 && reserveOut > 0, 'UniswapV2Library: INSUFFICIENT_LIQUIDITY');
        uint amountInWithFee = amountIn.mul(997);
        uint numerator = amountInWithFee.mul(reserveOut);
        uint denominator = reserveIn.mul(1000).add(amountInWithFee);
        amountOut = numerator / denominator;
    }

    // given an output amount of an asset and pair reserves, returns a required input amount of the other asset
    function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut) internal pure returns (uint amountIn) {
        require(amountOut > 0, 'UniswapV2Library: INSUFFICIENT_OUTPUT_AMOUNT');
        require(reserveIn > 0 && reserveOut > 0, 'UniswapV2Library: INSUFFICIENT_LIQUIDITY');
        uint numerator = reserveIn.mul(amountOut).mul(1000);
        uint denominator = reserveOut.sub(amountOut).mul(997);
        amountIn = (numerator / denominator).add(1);
    }

    // performs chained getAmountOut calculations on any number of pairs
    function getAmountsOut(address factory, uint amountIn, address[] memory path) internal view returns (uint[] memory amounts) {
        require(path.length >= 2, 'UniswapV2Library: INVALID_PATH');
        amounts = new uint[](path.length);
        amounts[0] = amountIn;
        for (uint i; i < path.length - 1; i++) {
            (uint reserveIn, uint reserveOut) = getReserves(factory, path[i], path[i + 1]);
            amounts[i + 1] = getAmountOut(amounts[i], reserveIn, reserveOut);
        }
    }

    // performs chained getAmountIn calculations on any number of pairs
    function getAmountsIn(address factory, uint amountOut, address[] memory path) internal view returns (uint[] memory amounts) {
        require(path.length >= 2, 'UniswapV2Library: INVALID_PATH');
        amounts = new uint[](path.length);
        amounts[amounts.length - 1] = amountOut;
        for (uint i = path.length - 1; i > 0; i--) {
            (uint reserveIn, uint reserveOut) = getReserves(factory, path[i - 1], path[i]);
            amounts[i - 1] = getAmountIn(amounts[i], reserveIn, reserveOut);
        }
    }
}

// helper methods for interacting with ERC20 tokens and sending ETH that do not consistently return true/false
library TransferHelper {
    function safeApprove(address token, address to, uint value) internal {
        // bytes4(keccak256(bytes('approve(address,uint256)')));
        (bool success, bytes memory data) = token.call(abi.encodeWithSelector(0x095ea7b3, to, value));
        require(success && (data.length == 0 || abi.decode(data, (bool))), 'TransferHelper: APPROVE_FAILED');
    }

    function safeTransfer(address token, address to, uint value) internal {
        // bytes4(keccak256(bytes('transfer(address,uint256)')));
        (bool success, bytes memory data) = token.call(abi.encodeWithSelector(0xa9059cbb, to, value));
        require(success && (data.length == 0 || abi.decode(data, (bool))), 'TransferHelper: TRANSFER_FAILED');
    }

    function safeTransferFrom(address token, address from, address to, uint value) internal {
        // bytes4(keccak256(bytes('transferFrom(address,address,uint256)')));
        (bool success, bytes memory data) = token.call(abi.encodeWithSelector(0x23b872dd, from, to, value));
        require(success && (data.length == 0 || abi.decode(data, (bool))), 'TransferHelper: TRANSFER_FROM_FAILED');
    }

    function safeTransferETH(address to, uint value) internal {
        (bool success,) = to.call{value:value}(new bytes(0));
        require(success, 'TransferHelper: ETH_TRANSFER_FAILED');
    }
}

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

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

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

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

pragma solidity ^0.4.18;

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

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

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

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

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

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

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

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

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

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

        Transfer(src, dst, wad);

        return true;
    }
}


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

 Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
 Everyone is permitted to copy and distribute verbatim copies
 of this license document, but changing it is not allowed.

                            Preamble

  The GNU General Public License is a free, copyleft license for
software and other kinds of works.

  The licenses for most software and other practical works are designed
to take away your freedom to share and change the works.  By contrast,
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share and change all versions of a program--to make sure it remains free
software for all its users.  We, the Free Software Foundation, use the
GNU General Public License for most of our software; it applies also to
any other work released this way by its authors.  You can apply it to
your programs, too.

  When we speak of free software, we are referring to freedom, not
price.  Our General Public Licenses are designed to make sure that you
have the freedom to distribute copies of free software (and charge for
them if you wish), that you receive source code or can get it if you
want it, that you can change the software or use pieces of it in new
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  To protect your rights, we need to prevent others from denying you
these rights or asking you to surrender the rights.  Therefore, you have
certain responsibilities if you distribute copies of the software, or if
you modify it: responsibilities to respect the freedom of others.

  For example, if you distribute copies of such a program, whether
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  Developers that use the GNU GPL protect your rights with two steps:
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  For the developers' and authors' protection, the GPL clearly explains
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  Some devices are designed to deny users access to install or run
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    regardless of how they are packaged.  This License gives no
    permission to license the work in any other way, but it does not
    invalidate such permission if you have separately received it.

    d) If the work has interactive user interfaces, each must display
    Appropriate Legal Notices; however, if the Program has interactive
    interfaces that do not display Appropriate Legal Notices, your
    work need not make them do so.

  A compilation of a covered work with other separate and independent
works, which are not by their nature extensions of the covered work,
and which are not combined with it such as to form a larger program,
in or on a volume of a storage or distribution medium, is called an
"aggregate" if the compilation and its resulting copyright are not
used to limit the access or legal rights of the compilation's users
beyond what the individual works permit.  Inclusion of a covered work
in an aggregate does not cause this License to apply to the other
parts of the aggregate.

  6. Conveying Non-Source Forms.

  You may convey a covered work in object code form under the terms
of sections 4 and 5, provided that you also convey the
machine-readable Corresponding Source under the terms of this License,
in one of these ways:

    a) Convey the object code in, or embodied in, a physical product
    (including a physical distribution medium), accompanied by the
    Corresponding Source fixed on a durable physical medium
    customarily used for software interchange.

    b) Convey the object code in, or embodied in, a physical product
    (including a physical distribution medium), accompanied by a
    written offer, valid for at least three years and valid for as
    long as you offer spare parts or customer support for that product
    model, to give anyone who possesses the object code either (1) a
    copy of the Corresponding Source for all the software in the
    product that is covered by this License, on a durable physical
    medium customarily used for software interchange, for a price no
    more than your reasonable cost of physically performing this
    conveying of source, or (2) access to copy the
    Corresponding Source from a network server at no charge.

    c) Convey individual copies of the object code with a copy of the
    written offer to provide the Corresponding Source.  This
    alternative is allowed only occasionally and noncommercially, and
    only if you received the object code with such an offer, in accord
    with subsection 6b.

    d) Convey the object code by offering access from a designated
    place (gratis or for a charge), and offer equivalent access to the
    Corresponding Source in the same way through the same place at no
    further charge.  You need not require recipients to copy the
    Corresponding Source along with the object code.  If the place to
    copy the object code is a network server, the Corresponding Source
    may be on a different server (operated by you or a third party)
    that supports equivalent copying facilities, provided you maintain
    clear directions next to the object code saying where to find the
    Corresponding Source.  Regardless of what server hosts the
    Corresponding Source, you remain obligated to ensure that it is
    available for as long as needed to satisfy these requirements.

    e) Convey the object code using peer-to-peer transmission, provided
    you inform other peers where the object code and Corresponding
    Source of the work are being offered to the general public at no
    charge under subsection 6d.

  A separable portion of the object code, whose source code is excluded
from the Corresponding Source as a System Library, need not be
included in conveying the object code work.

  A "User Product" is either (1) a "consumer product", which means any
tangible personal property which is normally used for personal, family,
or household purposes, or (2) anything designed or sold for incorporation
into a dwelling.  In determining whether a product is a consumer product,
doubtful cases shall be resolved in favor of coverage.  For a particular
product received by a particular user, "normally used" refers to a
typical or common use of that class of product, regardless of the status
of the particular user or of the way in which the particular user
actually uses, or expects or is expected to use, the product.  A product
is a consumer product regardless of whether the product has substantial
commercial, industrial or non-consumer uses, unless such uses represent
the only significant mode of use of the product.

  "Installation Information" for a User Product means any methods,
procedures, authorization keys, or other information required to install
and execute modified versions of a covered work in that User Product from
a modified version of its Corresponding Source.  The information must
suffice to ensure that the continued functioning of the modified object
code is in no case prevented or interfered with solely because
modification has been made.

  If you convey an object code work under this section in, or with, or
specifically for use in, a User Product, and the conveying occurs as
part of a transaction in which the right of possession and use of the
User Product is transferred to the recipient in perpetuity or for a
fixed term (regardless of how the transaction is characterized), the
Corresponding Source conveyed under this section must be accompanied
by the Installation Information.  But this requirement does not apply
if neither you nor any third party retains the ability to install
modified object code on the User Product (for example, the work has
been installed in ROM).

  The requirement to provide Installation Information does not include a
requirement to continue to provide support service, warranty, or updates
for a work that has been modified or installed by the recipient, or for
the User Product in which it has been modified or installed.  Access to a
network may be denied when the modification itself materially and
adversely affects the operation of the network or violates the rules and
protocols for communication across the network.

  Corresponding Source conveyed, and Installation Information provided,
in accord with this section must be in a format that is publicly
documented (and with an implementation available to the public in
source code form), and must require no special password or key for
unpacking, reading or copying.

  7. Additional Terms.

  "Additional permissions" are terms that supplement the terms of this
License by making exceptions from one or more of its conditions.
Additional permissions that are applicable to the entire Program shall
be treated as though they were included in this License, to the extent
that they are valid under applicable law.  If additional permissions
apply only to part of the Program, that part may be used separately
under those permissions, but the entire Program remains governed by
this License without regard to the additional permissions.

  When you convey a copy of a covered work, you may at your option
remove any additional permissions from that copy, or from any part of
it.  (Additional permissions may be written to require their own
removal in certain cases when you modify the work.)  You may place
additional permissions on material, added by you to a covered work,
for which you have or can give appropriate copyright permission.

  Notwithstanding any other provision of this License, for material you
add to a covered work, you may (if authorized by the copyright holders of
that material) supplement the terms of this License with terms:

    a) Disclaiming warranty or limiting liability differently from the
    terms of sections 15 and 16 of this License; or

    b) Requiring preservation of specified reasonable legal notices or
    author attributions in that material or in the Appropriate Legal
    Notices displayed by works containing it; or

    c) Prohibiting misrepresentation of the origin of that material, or
    requiring that modified versions of such material be marked in
    reasonable ways as different from the original version; or

    d) Limiting the use for publicity purposes of names of licensors or
    authors of the material; or

    e) Declining to grant rights under trademark law for use of some
    trade names, trademarks, or service marks; or

    f) Requiring indemnification of licensors and authors of that
    material by anyone who conveys the material (or modified versions of
    it) with contractual assumptions of liability to the recipient, for
    any liability that these contractual assumptions directly impose on
    those licensors and authors.

  All other non-permissive additional terms are considered "further
restrictions" within the meaning of section 10.  If the Program as you
received it, or any part of it, contains a notice stating that it is
governed by this License along with a term that is a further
restriction, you may remove that term.  If a license document contains
a further restriction but permits relicensing or conveying under this
License, you may add to a covered work material governed by the terms
of that license document, provided that the further restriction does
not survive such relicensing or conveying.

  If you add terms to a covered work in accord with this section, you
must place, in the relevant source files, a statement of the
additional terms that apply to those files, or a notice indicating
where to find the applicable terms.

  Additional terms, permissive or non-permissive, may be stated in the
form of a separately written license, or stated as exceptions;
the above requirements apply either way.

  8. Termination.

  You may not propagate or modify a covered work except as expressly
provided under this License.  Any attempt otherwise to propagate or
modify it is void, and will automatically terminate your rights under
this License (including any patent licenses granted under the third
paragraph of section 11).

  However, if you cease all violation of this License, then your
license from a particular copyright holder is reinstated (a)
provisionally, unless and until the copyright holder explicitly and
finally terminates your license, and (b) permanently, if the copyright
holder fails to notify you of the violation by some reasonable means
prior to 60 days after the cessation.

  Moreover, your license from a particular copyright holder is
reinstated permanently if the copyright holder notifies you of the
violation by some reasonable means, this is the first time you have
received notice of violation of this License (for any work) from that
copyright holder, and you cure the violation prior to 30 days after
your receipt of the notice.

  Termination of your rights under this section does not terminate the
licenses of parties who have received copies or rights from you under
this License.  If your rights have been terminated and not permanently
reinstated, you do not qualify to receive new licenses for the same
material under section 10.

  9. Acceptance Not Required for Having Copies.

  You are not required to accept this License in order to receive or
run a copy of the Program.  Ancillary propagation of a covered work
occurring solely as a consequence of using peer-to-peer transmission
to receive a copy likewise does not require acceptance.  However,
nothing other than this License grants you permission to propagate or
modify any covered work.  These actions infringe copyright if you do
not accept this License.  Therefore, by modifying or propagating a
covered work, you indicate your acceptance of this License to do so.

  10. Automatic Licensing of Downstream Recipients.

  Each time you convey a covered work, the recipient automatically
receives a license from the original licensors, to run, modify and
propagate that work, subject to this License.  You are not responsible
for enforcing compliance by third parties with this License.

  An "entity transaction" is a transaction transferring control of an
organization, or substantially all assets of one, or subdividing an
organization, or merging organizations.  If propagation of a covered
work results from an entity transaction, each party to that
transaction who receives a copy of the work also receives whatever
licenses to the work the party's predecessor in interest had or could
give under the previous paragraph, plus a right to possession of the
Corresponding Source of the work from the predecessor in interest, if
the predecessor has it or can get it with reasonable efforts.

  You may not impose any further restrictions on the exercise of the
rights granted or affirmed under this License.  For example, you may
not impose a license fee, royalty, or other charge for exercise of
rights granted under this License, and you may not initiate litigation
(including a cross-claim or counterclaim in a lawsuit) alleging that
any patent claim is infringed by making, using, selling, offering for
sale, or importing the Program or any portion of it.

  11. Patents.

  A "contributor" is a copyright holder who authorizes use under this
License of the Program or a work on which the Program is based.  The
work thus licensed is called the contributor's "contributor version".

  A contributor's "essential patent claims" are all patent claims
owned or controlled by the contributor, whether already acquired or
hereafter acquired, that would be infringed by some manner, permitted
by this License, of making, using, or selling its contributor version,
but do not include claims that would be infringed only as a
consequence of further modification of the contributor version.  For
purposes of this definition, "control" includes the right to grant
patent sublicenses in a manner consistent with the requirements of
this License.

  Each contributor grants you a non-exclusive, worldwide, royalty-free
patent license under the contributor's essential patent claims, to
make, use, sell, offer for sale, import and otherwise run, modify and
propagate the contents of its contributor version.

  In the following three paragraphs, a "patent license" is any express
agreement or commitment, however denominated, not to enforce a patent
(such as an express permission to practice a patent or covenant not to
sue for patent infringement).  To "grant" such a patent license to a
party means to make such an agreement or commitment not to enforce a
patent against the party.

  If you convey a covered work, knowingly relying on a patent license,
and the Corresponding Source of the work is not available for anyone
to copy, free of charge and under the terms of this License, through a
publicly available network server or other readily accessible means,
then you must either (1) cause the Corresponding Source to be so
available, or (2) arrange to deprive yourself of the benefit of the
patent license for this particular work, or (3) arrange, in a manner
consistent with the requirements of this License, to extend the patent
license to downstream recipients.  "Knowingly relying" means you have
actual knowledge that, but for the patent license, your conveying the
covered work in a country, or your recipient's use of the covered work
in a country, would infringe one or more identifiable patents in that
country that you have reason to believe are valid.

  If, pursuant to or in connection with a single transaction or
arrangement, you convey, or propagate by procuring conveyance of, a
covered work, and grant a patent license to some of the parties
receiving the covered work authorizing them to use, propagate, modify
or convey a specific copy of the covered work, then the patent license
you grant is automatically extended to all recipients of the covered
work and works based on it.

  A patent license is "discriminatory" if it does not include within
the scope of its coverage, prohibits the exercise of, or is
conditioned on the non-exercise of one or more of the rights that are
specifically granted under this License.  You may not convey a covered
work if you are a party to an arrangement with a third party that is
in the business of distributing software, under which you make payment
to the third party based on the extent of your activity of conveying
the work, and under which the third party grants, to any of the
parties who would receive the covered work from you, a discriminatory
patent license (a) in connection with copies of the covered work
conveyed by you (or copies made from those copies), or (b) primarily
for and in connection with specific products or compilations that
contain the covered work, unless you entered into that arrangement,
or that patent license was granted, prior to 28 March 2007.

  Nothing in this License shall be construed as excluding or limiting
any implied license or other defenses to infringement that may
otherwise be available to you under applicable patent law.

  12. No Surrender of Others' Freedom.

  If conditions are imposed on you (whether by court order, agreement or
otherwise) that contradict the conditions of this License, they do not
excuse you from the conditions of this License.  If you cannot convey a
covered work so as to satisfy simultaneously your obligations under this
License and any other pertinent obligations, then as a consequence you may
not convey it at all.  For example, if you agree to terms that obligate you
to collect a royalty for further conveying from those to whom you convey
the Program, the only way you could satisfy both those terms and this
License would be to refrain entirely from conveying the Program.

  13. Use with the GNU Affero General Public License.

  Notwithstanding any other provision of this License, you have
permission to link or combine any covered work with a work licensed
under version 3 of the GNU Affero General Public License into a single
combined work, and to convey the resulting work.  The terms of this
License will continue to apply to the part which is the covered work,
but the special requirements of the GNU Affero General Public License,
section 13, concerning interaction through a network will apply to the
combination as such.

  14. Revised Versions of this License.

  The Free Software Foundation may publish revised and/or new versions of
the GNU General Public License from time to time.  Such new versions will
be similar in spirit to the present version, but may differ in detail to
address new problems or concerns.

  Each version is given a distinguishing version number.  If the
Program specifies that a certain numbered version of the GNU General
Public License "or any later version" applies to it, you have the
option of following the terms and conditions either of that numbered
version or of any later version published by the Free Software
Foundation.  If the Program does not specify a version number of the
GNU General Public License, you may choose any version ever published
by the Free Software Foundation.

  If the Program specifies that a proxy can decide which future
versions of the GNU General Public License can be used, that proxy's
public statement of acceptance of a version permanently authorizes you
to choose that version for the Program.

  Later license versions may give you additional or different
permissions.  However, no additional obligations are imposed on any
author or copyright holder as a result of your choosing to follow a
later version.

  15. Disclaimer of Warranty.

  THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
ALL NECESSARY SERVICING, REPAIR OR CORRECTION.

  16. Limitation of Liability.

  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
SUCH DAMAGES.

  17. Interpretation of Sections 15 and 16.

  If the disclaimer of warranty and limitation of liability provided
above cannot be given local legal effect according to their terms,
reviewing courts shall apply local law that most closely approximates
an absolute waiver of all civil liability in connection with the
Program, unless a warranty or assumption of liability accompanies a
copy of the Program in return for a fee.

                     END OF TERMS AND CONDITIONS

            How to Apply These Terms to Your New Programs

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

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

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

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

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

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

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

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

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

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

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

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

*/