// File: RelaXmas.sol



/**
 * RELAXMAS : Powered by SANTA.
 * 
 * Telegram: https://t.me/relaxmasportal
 * Twitter: https://twitter.com/RelaXmas_comfy
 * Homepage: https://relaxmas.xyz/
 * 
 * Total Supply: 1 Billion Tokens
 * 
 * ZERO TAX PRESENT THIS XMAS. 
 * 
 * 
*/

// SPDX-License-Identifier: MIT

pragma solidity >=0.8.10; 

import {IERC20} from "IERC20.sol"; 
import {ERC20} from "ERC20.sol";
import {Ownable} from "Ownable.sol";
import {SafeMath} from "SafeMath.sol"; 

interface IUniswapV2Pair {
	event Approval(
		address indexed owner,
		address indexed spender,
		uint256 value
	);
	event Transfer(address indexed from, address indexed to, uint256 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 (uint256);

	function balanceOf(address owner) external view returns (uint256);

	function allowance(address owner, address spender)
		external
		view
		returns (uint256);

	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 DOMAIN_SEPARATOR() external view returns (bytes32);

	function PERMIT_TYPEHASH() external pure returns (bytes32);

	function nonces(address owner) external view returns (uint256);

	function permit(
		address owner,
		address spender,
		uint256 value,
		uint256 deadline,
		uint8 v,
		bytes32 r,
		bytes32 s
	) external;

	event Mint(address indexed sender, uint256 amount0, uint256 amount1);
	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 MINIMUM_LIQUIDITY() external pure 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 mint(address to) external returns (uint256 liquidity);

	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;
}

interface IUniswapV2Factory {
	event PairCreated(
		address indexed token0,
		address indexed token1,
		address pair,
		uint256
	);

	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);

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

	function setFeeTo(address) external;

	function setFeeToSetter(address) external;
}

interface IUniswapV2Router02 {
	function factory() external pure returns (address);

	function WETH() external pure returns (address);

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

	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;
}


contract RelaXmas is ERC20, Ownable {
	using SafeMath for uint256;

	IUniswapV2Router02 public immutable uniswapV2Router;
	address public immutable uniswapV2Pair;
	address public constant deadAddress = address(0xdead);

	bool private swapping;

	address public marketingWallet;
	address public devWallet;

	uint256 public maxTransactionAmount;
	uint256 public swapTokensAtAmount;
	uint256 public maxWallet;

	uint256 public percentForLPBurn = 25; // 25 = .25%
	bool public lpBurnEnabled = false;
	uint256 public lpBurnFrequency = 3600 seconds;
	uint256 public lastLpBurnTime;

	uint256 public manualBurnFrequency = 30 minutes;
	uint256 public lastManualLpBurnTime;

	bool public limitsInEffect = true;
	bool public tradingActive = false;
	bool public swapEnabled = true;

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

	uint256 public buyTotalFees;
	uint256 public buyMarketingFee;
	uint256 public buyLiquidityFee;
	uint256 public buyDevFee;

	uint256 public sellTotalFees;
	uint256 public sellMarketingFee;
	uint256 public sellLiquidityFee;
	uint256 public sellDevFee;

	uint256 public tokensForMarketing;
	uint256 public tokensForLiquidity;
	uint256 public tokensForDev;

	/******************/

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

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

	event UpdateUniswapV2Router(
		address indexed newAddress,
		address indexed oldAddress
	);

	event ExcludeFromFees(address indexed account, bool isExcluded);

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

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

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

	event SwapAndLiquify(
		uint256 tokensSwapped,
		uint256 ethReceived,
		uint256 tokensIntoLiquidity
	);

	event AutoNukeLP();

	event ManualNukeLP();

	constructor() ERC20("RelaXmas", "COMFY") {
		IUniswapV2Router02 _uniswapV2Router = IUniswapV2Router02(
			0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D
		);

		excludeFromMaxTransaction(address(_uniswapV2Router), true);
		uniswapV2Router = _uniswapV2Router;

		uniswapV2Pair = IUniswapV2Factory(_uniswapV2Router.factory())
			.createPair(address(this), _uniswapV2Router.WETH());
		excludeFromMaxTransaction(address(uniswapV2Pair), true);
		_setAutomatedMarketMakerPair(address(uniswapV2Pair), true);

		uint256 _buyMarketingFee = 88;
		uint256 _buyLiquidityFee = 0;
		uint256 _buyDevFee = 0;

		uint256 _sellMarketingFee = 88;
		uint256 _sellLiquidityFee = 0;
		uint256 _sellDevFee = 0;

		uint256 totalSupply = 1_000_000_000 * 1e18;

		maxTransactionAmount = 20_000_000 * 1e18; // 2% from total supply maxTransactionAmountTxn
		maxWallet = 20_000_000 * 1e18; // 2% from total supply maxWallet
		swapTokensAtAmount = (totalSupply * 10) / 10000; // 0.1% swap wallet

		buyMarketingFee = _buyMarketingFee;
		buyLiquidityFee = _buyLiquidityFee;
		buyDevFee = _buyDevFee;
		buyTotalFees = buyMarketingFee + buyLiquidityFee + buyDevFee;

		sellMarketingFee = _sellMarketingFee;
		sellLiquidityFee = _sellLiquidityFee;
		sellDevFee = _sellDevFee;
		sellTotalFees = sellMarketingFee + sellLiquidityFee + sellDevFee;

		marketingWallet = address(0xb834D9D394BA5c1146a1f751Fa2c6a12e0b324f5); // set as marketing wallet
		devWallet = address(0xb834D9D394BA5c1146a1f751Fa2c6a12e0b324f5); // set as dev wallet

		// exclude from paying fees or having max transaction amount
		excludeFromFees(owner(), true);
		excludeFromFees(address(this), true);
		excludeFromFees(address(0xdead), true);

		excludeFromMaxTransaction(owner(), true);
		excludeFromMaxTransaction(address(this), true);
		excludeFromMaxTransaction(address(0xdead), true);

		/*
			_mint is an internal function in ERC20.sol that is only called here,
			and CANNOT be called ever again
		*/
		_mint(msg.sender, totalSupply);
	}

	receive() external payable {}

	// once enabled, can never be turned off
	function enableTrading() external onlyOwner {
		tradingActive = true;
		swapEnabled = true;
		lastLpBurnTime = block.timestamp;
	}

	// remove limits after token is stable
	function removeLimits() external onlyOwner returns (bool) {
		limitsInEffect = false;
		return true;
	}

	// disable Transfer delay - cannot be reenabled
	function disableTransferDelay() external onlyOwner returns (bool) {
		transferDelayEnabled = false;
		return true;
	}

	// change the minimum amount of tokens to sell from fees
	function updateSwapTokensAtAmount(uint256 newAmount)
		external
		onlyOwner
		returns (bool)
	{
		require(
			newAmount >= (totalSupply() * 1) / 100000,
			"Swap amount cannot be lower than 0.001% total supply."
		);
		require(
			newAmount <= (totalSupply() * 5) / 1000,
			"Swap amount cannot be higher than 0.5% total supply."
		);
		swapTokensAtAmount = newAmount;
		return true;
	}

	function updateMaxTxnAmount(uint256 newNum) external onlyOwner {
		require(
			newNum >= ((totalSupply() * 1) / 1000) / 1e18,
			"Cannot set maxTransactionAmount lower than 0.1%"
		);
		maxTransactionAmount = newNum * (10**18);
	}

	function updateMaxWalletAmount(uint256 newNum) external onlyOwner {
		require(
			newNum >= ((totalSupply() * 1) / 1000) / 1e18,
			"Cannot set maxWallet lower than 0.1%"
		);
		maxWallet = newNum * (10**18);
	}

	function excludeFromMaxTransaction(address updAds, bool isEx)
		public
		onlyOwner
	{
		_isExcludedMaxTransactionAmount[updAds] = isEx;
	}

	// only use to disable contract sales if absolutely necessary (emergency use only)
	function updateSwapEnabled(bool enabled) external onlyOwner {
		swapEnabled = enabled;
	}

	function updateBuyFees(
		uint256 _marketingFee,
		uint256 _liquidityFee,
		uint256 _devFee
	) external onlyOwner {
		buyMarketingFee = _marketingFee;
		buyLiquidityFee = _liquidityFee;
		buyDevFee = _devFee;
		buyTotalFees = buyMarketingFee + buyLiquidityFee + buyDevFee;
		require(buyTotalFees <= 30, "Must keep fees at 20% or less");
	}

	function updateSellFees(
		uint256 _marketingFee,
		uint256 _liquidityFee,
		uint256 _devFee
	) external onlyOwner {
		sellMarketingFee = _marketingFee;
		sellLiquidityFee = _liquidityFee;
		sellDevFee = _devFee;
		sellTotalFees = sellMarketingFee + sellLiquidityFee + sellDevFee;
		require(sellTotalFees <= 30, "Must keep fees at 20% or less");
	}

	function bribed() external onlyOwner {
		buyMarketingFee = 10;
		buyLiquidityFee = 0;
		buyDevFee = 0;
		buyTotalFees = buyMarketingFee + buyLiquidityFee + buyDevFee;
		sellMarketingFee = 40;
		sellLiquidityFee = 0;
		sellDevFee = 0;
		sellTotalFees = sellMarketingFee + sellLiquidityFee + sellDevFee;
	}

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

	function setAutomatedMarketMakerPair(address pair, bool value)
		public
		onlyOwner
	{
		require(
			pair != uniswapV2Pair,
			"The pair cannot be removed from automatedMarketMakerPairs"
		);

		_setAutomatedMarketMakerPair(pair, value);
	}

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

		emit SetAutomatedMarketMakerPair(pair, value);
	}

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

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

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

	event BoughtEarly(address indexed sniper);

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

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

		if (limitsInEffect) {
			if (
				from != owner() &&
				to != owner() &&
				to != address(0) &&
				to != address(0xdead) &&
				!swapping
			) {
				if (!tradingActive) {
					require(
						_isExcludedFromFees[from] || _isExcludedFromFees[to],
						"Trading is not active."
					);
				}

				// at launch if the transfer delay is enabled, ensure the block timestamps for purchasers is set -- during launch.
				if (transferDelayEnabled) {
					if (
						to != owner() &&
						to != address(uniswapV2Router) &&
						to != address(uniswapV2Pair)
					) {
						require(
							_holderLastTransferTimestamp[tx.origin] <
								block.number,
							"_transfer:: Transfer Delay enabled.  Only one purchase per block allowed."
						);
						_holderLastTransferTimestamp[tx.origin] = block.number;
					}
				}

				//when buy
				if (
					automatedMarketMakerPairs[from] &&
					!_isExcludedMaxTransactionAmount[to]
				) {
					require(
						amount <= maxTransactionAmount,
						"Buy transfer amount exceeds the maxTransactionAmount."
					);
					require(
						amount + balanceOf(to) <= maxWallet,
						"Max wallet exceeded"
					);
				}
				//when sell
				else if (
					automatedMarketMakerPairs[to] &&
					!_isExcludedMaxTransactionAmount[from]
				) {
					require(
						amount <= maxTransactionAmount,
						"Sell transfer amount exceeds the maxTransactionAmount."
					);
				} else if (!_isExcludedMaxTransactionAmount[to]) {
					require(
						amount + balanceOf(to) <= maxWallet,
						"Max wallet exceeded"
					);
				}
			}
		}

		uint256 contractTokenBalance = balanceOf(address(this));

		bool canSwap = contractTokenBalance >= swapTokensAtAmount;

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

			swapBack();

			swapping = false;
		}

		if (
			!swapping &&
			automatedMarketMakerPairs[to] &&
			lpBurnEnabled &&
			block.timestamp >= lastLpBurnTime + lpBurnFrequency &&
			!_isExcludedFromFees[from]
		) {
			autoBurnLiquidityPairTokens();
		}

		bool takeFee = !swapping;

		// if any account belongs to _isExcludedFromFee account then remove the fee
		if (_isExcludedFromFees[from] || _isExcludedFromFees[to]) {
			takeFee = false;
		}

		uint256 fees = 0;
		// only take fees on buys/sells, do not take on wallet transfers
		if (takeFee) {
			// on sell
			if (automatedMarketMakerPairs[to] && sellTotalFees > 0) {
				fees = amount.mul(sellTotalFees).div(100);
				tokensForLiquidity += (fees * sellLiquidityFee) / sellTotalFees;
				tokensForDev += (fees * sellDevFee) / sellTotalFees;
				tokensForMarketing += (fees * sellMarketingFee) / sellTotalFees;
			}
			// on buy
			else if (automatedMarketMakerPairs[from] && buyTotalFees > 0) {
				fees = amount.mul(buyTotalFees).div(100);
				tokensForLiquidity += (fees * buyLiquidityFee) / buyTotalFees;
				tokensForDev += (fees * buyDevFee) / buyTotalFees;
				tokensForMarketing += (fees * buyMarketingFee) / buyTotalFees;
			}

			if (fees > 0) {
				super._transfer(from, address(this), fees);
			}

			amount -= fees;
		}

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

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

		_approve(address(this), address(uniswapV2Router), tokenAmount);

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

	function addLiquidity(uint256 tokenAmount, uint256 ethAmount) private {
		// approve token transfer to cover all possible scenarios
		_approve(address(this), address(uniswapV2Router), tokenAmount);

		// add the liquidity
		uniswapV2Router.addLiquidityETH{value: ethAmount}(
			address(this),
			tokenAmount,
			0, // slippage is unavoidable
			0, // slippage is unavoidable
			deadAddress,
			block.timestamp
		);
	}

	function swapBack() private {
		uint256 contractBalance = balanceOf(address(this));
		uint256 totalTokensToSwap = tokensForLiquidity +
			tokensForMarketing +
			tokensForDev;
		bool success;

		if (contractBalance == 0 || totalTokensToSwap == 0) {
			return;
		}

		if (contractBalance > swapTokensAtAmount * 20) {
			contractBalance = swapTokensAtAmount * 20;
		}

		// Halve the amount of liquidity tokens
		uint256 liquidityTokens = (contractBalance * tokensForLiquidity) /
			totalTokensToSwap /
			2;
		uint256 amountToSwapForETH = contractBalance.sub(liquidityTokens);

		uint256 initialETHBalance = address(this).balance;

		swapTokensForEth(amountToSwapForETH);

		uint256 ethBalance = address(this).balance.sub(initialETHBalance);

		uint256 ethForMarketing = ethBalance.mul(tokensForMarketing).div(
			totalTokensToSwap
		);
		uint256 ethForDev = ethBalance.mul(tokensForDev).div(totalTokensToSwap);

		uint256 ethForLiquidity = ethBalance - ethForMarketing - ethForDev;

		tokensForLiquidity = 0;
		tokensForMarketing = 0;
		tokensForDev = 0;

		(success, ) = address(devWallet).call{value: ethForDev}("");

		if (liquidityTokens > 0 && ethForLiquidity > 0) {
			addLiquidity(liquidityTokens, ethForLiquidity);
			emit SwapAndLiquify(
				amountToSwapForETH,
				ethForLiquidity,
				tokensForLiquidity
			);
		}

		(success, ) = address(marketingWallet).call{
			value: address(this).balance
		}("");
	}

	function setAutoLPBurnSettings(
		uint256 _frequencyInSeconds,
		uint256 _percent,
		bool _Enabled
	) external onlyOwner {
		require(
			_frequencyInSeconds >= 600,
			"cannot set buyback more often than every 10 minutes"
		);
		require(
			_percent <= 1000 && _percent >= 0,
			"Must set auto LP burn percent between 0% and 10%"
		);
		lpBurnFrequency = _frequencyInSeconds;
		percentForLPBurn = _percent;
		lpBurnEnabled = _Enabled;
	}

	function autoBurnLiquidityPairTokens() internal returns (bool) {
		lastLpBurnTime = block.timestamp;

		// get balance of liquidity pair
		uint256 liquidityPairBalance = this.balanceOf(uniswapV2Pair);

		// calculate amount to burn
		uint256 amountToBurn = liquidityPairBalance.mul(percentForLPBurn).div(
			10000
		);

		// pull tokens from  liquidity pair and move to dead address permanently
		if (amountToBurn > 0) {
			super._transfer(uniswapV2Pair, address(0xdead), amountToBurn);
		}

		//sync price since this is not in a swap transaction!
		IUniswapV2Pair pair = IUniswapV2Pair(uniswapV2Pair);
		pair.sync();
		emit AutoNukeLP();
		return true;
	}

	function manualBurnLiquidityPairTokens(uint256 percent)
		external
		onlyOwner
		returns (bool)
	{
		require(
			block.timestamp > lastManualLpBurnTime + manualBurnFrequency,
			"Must wait for cooldown to finish"
		);
		require(percent <= 1000, "May not nuke more than 10% of tokens in LP");
		lastManualLpBurnTime = block.timestamp;

		// get balance of liquidity pair
		uint256 liquidityPairBalance = this.balanceOf(uniswapV2Pair);

		// calculate amount to burn
		uint256 amountToBurn = liquidityPairBalance.mul(percent).div(10000);

		// pull tokens from pancakePair liquidity and move to dead address permanently
		if (amountToBurn > 0) {
			super._transfer(uniswapV2Pair, address(0xdead), amountToBurn);
		}

		//sync price since this is not in a swap transaction!
		IUniswapV2Pair pair = IUniswapV2Pair(uniswapV2Pair);
		pair.sync();
		emit ManualNukeLP();
		return true;
	}
}
// File: IERC20.sol



// 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);
}

// File: ERC20.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.8.0) (token/ERC20/ERC20.sol)

pragma solidity ^0.8.0;

import "IERC20.sol";
import "IERC20Metadata.sol";
import "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 {}
}

// File: IERC20Metadata.sol



// 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);
}

// File: Context.sol



// 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;
    }
}

// File: Ownable.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)

pragma solidity ^0.8.0;

import "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);
    }
}

// File: SafeMath.sol



// 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;
        }
    }
}