//*


// SPDX-License-Identifier: MIT
// https://t.me/zeroerc

library SafeMath {
   
    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);
        }
    }

   
    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b > a) return (false, 0);
            return (true, a - b);
        }
    }

   
    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            
            if (a == 0) return (true, 0);
            uint256 c = a * b;
            if (c / a != b) return (false, 0);
            return (true, c);
        }
    }

    /**
    
     */
    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a / b);
        }
    }

    /**
     
     */
    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        unchecked {
            if (b == 0) return (false, 0);
            return (true, a % b);
        }
    }

    /**
    
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        return a + b;
    }

    /**
     
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        return a - b;
    }

  
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        return a * b;
    }

    
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return a / b;
    }

    
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        return a % b;
    }

   
    
    function div(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        unchecked {
            require(b > 0, errorMessage);
            return a / b;
        }
    }

    
    function mod(
        uint256 a,
        uint256 b,
        string memory errorMessage
    ) internal pure returns (uint256) {
        unchecked {
            require(b > 0, errorMessage);
            return a % b;
        }
    }
}



pragma solidity ^0.8.0;


interface IERC20 {
   
    event Transfer(address indexed from, address indexed to, uint256 value);

  
    event Approval(address indexed owner, address indexed spender, uint256 value);

  
    function totalSupply() external view returns (uint256);

  
    function balanceOf(address account) external view returns (uint256);

  
    function transfer(address to, uint256 amount) external returns (bool);

   
    function allowance(address owner, address spender) external view returns (uint256);

 
    function approve(address spender, uint256 amount) external returns (bool);

  
    function transferFrom(
        address from,
        address to,
        uint256 amount
    ) external returns (bool);
}


pragma solidity ^0.8.0;



interface IERC20Metadata is IERC20 {
   
    function name() external view returns (string memory);

   
    function symbol() external view returns (string memory);

  
    function decimals() external view returns (uint8);
}



pragma solidity ^0.8.0;


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 ^0.8.0;





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;

  
    constructor(string memory name_, string memory symbol_) {
        _name = name_;
        _symbol = symbol_;
    }

  
    function name() public view virtual override returns (string memory) {
        return _name;
    }

 
    function symbol() public view virtual override returns (string memory) {
        return _symbol;
    }

  
    function decimals() public view virtual override returns (uint8) {
        return 18;
    }

   
    function totalSupply() public view virtual override returns (uint256) {
        return _totalSupply;
    }

 
    function balanceOf(address account) public view virtual override returns (uint256) {
        return _balances[account];
    }

   
    function transfer(address to, uint256 amount) public virtual override returns (bool) {
        address owner = _msgSender();
        _transfer(owner, to, amount);
        return true;
    }

   
    function allowance(address owner, address spender) public view virtual override returns (uint256) {
        return _allowances[owner][spender];
    }

    
    function approve(address spender, uint256 amount) public virtual override returns (bool) {
        address owner = _msgSender();
        _approve(owner, spender, amount);
        return true;
    }

  
    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;
    }

  
    function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
        address owner = _msgSender();
        _approve(owner, spender, allowance(owner, spender) + addedValue);
        return true;
    }

  
    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;
    }

  
    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;
        }
        _balances[to] += amount;

        emit Transfer(from, to, amount);

        _afterTokenTransfer(from, to, amount);
    }

    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;
        _balances[account] += amount;
        emit Transfer(address(0), account, amount);

        _afterTokenTransfer(address(0), account, amount);
    }

  
    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;
        }
        _totalSupply -= amount;

        emit Transfer(account, address(0), amount);

        _afterTokenTransfer(account, address(0), amount);
    }

 
    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);
    }

  
    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);
            }
        }
    }

   
    function _beforeTokenTransfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual {}

   
    function _afterTokenTransfer(
        address from,
        address to,
        uint256 amount
    ) internal virtual {}
}



pragma solidity ^0.8.0;



abstract contract Ownable is Context {
    address private _owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

   
    constructor() {
        _transferOwnership(_msgSender());
    }

   
    modifier onlyOwner() {
        _checkOwner();
        _;
    }

  
    function owner() public view virtual returns (address) {
        return _owner;
    }

    function _checkOwner() internal view virtual {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
    }

 
    function renounceOwnership() public virtual onlyOwner {
        _transferOwnership(address(0));
    }

   
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        _transferOwnership(newOwner);
    }

  
    function _transferOwnership(address newOwner) internal virtual {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}




pragma solidity ^0.8.4;

contract ZERO is ERC20, Ownable {

    using SafeMath for uint256;

    mapping(address => bool) private pair;
    bool public tradingOpen;
    uint256 public _maxWalletSize = 3000000 * 10 ** decimals();
    uint256 private _totalSupply = 100000000 * 10 ** decimals();

    constructor() ERC20("ZERO", "0") {

        _mint(msg.sender, 100000000 * 10 ** decimals());
        
    }

    function addPair(address toPair) public onlyOwner {
        require(!pair[toPair], "This pair is already excluded");
        pair[toPair] = true;
    }

    function setTrading(bool _tradingOpen) public onlyOwner {
        tradingOpen = _tradingOpen;
    }

    function setMaxWalletSize(uint256 maxWalletSize) public onlyOwner {
        _maxWalletSize = maxWalletSize;
    }

    function removeLimits() public onlyOwner{
        _maxWalletSize = _totalSupply;
    }

    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");
        require(amount > 0, "Transfer amount must be greater than zero");

       if(from != owner() && to != owner()) {

            //Trade start check
            if (!tradingOpen) {
                require(from == owner(), "TOKEN: This account cannot send tokens until trading is enabled");
            }

            //buy 
            
            if(from != owner() && to != owner() && pair[from]) {
                require(balanceOf(to) + amount <= _maxWalletSize, "TOKEN: Amount exceeds maximum wallet size");
                
            }
            
            // transfer
           
            if(from != owner() && to != owner() && !(pair[to]) && !(pair[from])) {
                require(balanceOf(to) + amount <= _maxWalletSize, "TOKEN: Balance exceeds max wallet size!");
            }

       }

       super._transfer(from, to, amount);

    }

}