// Vulnerability label: clean
pragma solidity ^0.4.23;


/**
 * @title IERC20Token - ERC20 interface
 * @dev see https://github.com/ethereum/EIPs/issues/20
 */
contract IERC20Token {
    string public name;
    string public symbol;
    uint8 public decimals;
    uint256 public totalSupply;

    function balanceOf(address _owner) public constant returns (uint256 balance);

    function transfer(address _to, uint256 _value) public returns (bool success);

    function transferFrom(address _from, address _to, uint256 _value) public returns (bool success);

    function approve(address _spender, uint256 _value) public returns (bool success);

    function allowance(address _owner, address _spender) public constant returns (uint256 remaining);

    event Transfer(address indexed _from, address indexed _to, uint256 _value);
    event Approval(address indexed _owner, address indexed _spender, uint256 _value);
}

/**
 * @title SafeMath
 * @dev Math operations with safety checks that throw on error
 */
contract SafeMath {
    /**
    * @dev constructor
    */
    constructor() public {
    }

    function safeMul(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a * b;
        assert(a == 0 || c / a == b);
        return c;
    }

    function safeDiv(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a / b;
        return c;
    }

    function safeSub(uint256 a, uint256 b) internal pure returns (uint256) {
        assert(a >= b);
        return a - b;
    }

    function safeAdd(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        assert(c >= a);
        return c;
    }
}

/**
 * @title ERC20Token - ERC20 base implementation
 * @dev see https://github.com/ethereum/EIPs/issues/20
 */
contract ERC20Token is IERC20Token, SafeMath {
    mapping(address => uint256) public balances;
    mapping(address => mapping(address => uint256)) public allowed;

    function transfer(address _to, uint256 _value) public returns (bool) {
        require(_to != address(0));
        require(balances[msg.sender] >= _value);

        balances[msg.sender] = safeSub(balances[msg.sender], _value);
        balances[_to] = safeAdd(balances[_to], _value);
        emit Transfer(msg.sender, _to, _value);
        return true;
    }

    function transferFrom(address _from, address _to, uint256 _value) public returns (bool) {
        require(_to != address(0));
        require(balances[_from] >= _value && allowed[_from][msg.sender] >= _value);

        balances[_to] = safeAdd(balances[_to], _value);
        balances[_from] = safeSub(balances[_from], _value);
        allowed[_from][msg.sender] = safeSub(allowed[_from][msg.sender], _value);
        emit Transfer(_from, _to, _value);
        return true;
    }

    function balanceOf(address _owner) public constant returns (uint256) {
        return balances[_owner];
    }

    function approve(address _spender, uint256 _value) public returns (bool) {
        allowed[msg.sender][_spender] = _value;
        emit Approval(msg.sender, _spender, _value);
        return true;
    }

    function allowance(address _owner, address _spender) public constant returns (uint256) {
        return allowed[_owner][_spender];
    }
}

contract Linkart is ERC20Token {

    uint256 public mintTotal;
    address public owner;

    event Mint(address _toAddress, uint256 _amount);

    constructor(address _owner) public {
        require(address(0) != _owner);

        name = "Linkart";
        symbol = "LAR";
        decimals = 18;
        totalSupply = 10 * 1000 * 1000 * 1000 * 10 ** uint256(decimals);

        mintTotal = 0;
        owner = _owner;
    }

    function mint(address _toAddress, uint256 _amount) public returns (bool) {
        require(msg.sender == owner);
        require(address(0) != _toAddress);
        require(_amount >= 0);
        require(safeAdd(_amount, mintTotal) <= totalSupply);

        mintTotal = safeAdd(_amount, mintTotal);
        balances[_toAddress] = safeAdd(balances[_toAddress], _amount);

        emit Mint(_toAddress, _amount);
        return (true);
    }

    function() public payable {
        revert();
    }
}