pragma solidity >=0.4.22 <0.6.0;

contract ERC20 {
    uint256 public totalSupply;
    function balanceOf(address _owner) view public  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) view public returns (uint256 remaining);

    event Transfer(address indexed _from, address indexed _to, uint256 _value);
    event Approval(address indexed _owner, address indexed _spender, uint256 _value);
}

library SafeMath {
  function mul(uint a, uint b) internal pure returns (uint) {
    uint c = a * b;
    assert(a == 0 || c / a == b);
    return c;
  }

  function div(uint a, uint b) internal pure returns (uint) {
    uint c = a / b;
    return c;
  }

  function sub(uint a, uint b) internal pure returns (uint) {
    assert(b <= a);
    return a - b;
  }

  function add(uint a, uint b) internal pure returns (uint) {
    uint c = a + b;
    assert(c >= a);
    return c;
  }

  function max64(uint64 a, uint64 b) internal pure returns (uint64) {
    return a >= b ? a : b;
  }

  function min64(uint64 a, uint64 b) internal pure returns (uint64) {
    return a < b ? a : b;
  }

  function max256(uint256 a, uint256 b) internal pure returns (uint256) {
    return a >= b ? a : b;
  }

  function min256(uint256 a, uint256 b) internal pure returns (uint256) {
    return a < b ? a : b;
  }


}

contract Token is ERC20 {

    using SafeMath for uint;
    mapping (address => uint256) balances;
    mapping (address => mapping (address => uint256)) allowed;
    string public name;
    uint8 public decimals;
    string public symbol;

    constructor(uint256 _initialAmount, uint8 _decimalUnits, string memory _tokenName, string memory _tokenSymbol) public {
        decimals = _decimalUnits;
        totalSupply = _initialAmount * 10**uint(decimals);
        balances[msg.sender] = totalSupply;
        name = _tokenName;
        symbol = _tokenSymbol;   
    }

    function balanceOf(address _owner) view public returns (uint256 balance) {
        return balances[_owner];
    }

    function transfer(address _to, uint256 _value) public returns (bool success) {
        require(balances[msg.sender] >= _value && _value > 0); 
        balances[msg.sender] = balances[msg.sender].sub(_value);
        balances[_to] = balances[_to].add(_value);
        emit Transfer(msg.sender, _to, _value);
        return true;
        
    }

    function transferFrom(address _from, address _to, uint256 _value) public returns (bool success) {
        require(balances[_from] >= _value && allowed[_from][msg.sender] >= _value && _value > 0); 
        uint256 _allowance = allowed[_from][msg.sender];
        balances[_to] = balances[_to].add(_value);
        balances[_from] = balances[_from].sub(_value);
        allowed[_from][msg.sender] = _allowance.sub(_value);
        emit Transfer(_from, _to, _value);
        return true;
    }

    function approve(address _spender, uint256 _value) public returns (bool success) {
        require(_value >= 0); 
        allowed[msg.sender][_spender] = _value;
        emit Approval(msg.sender, _spender, _value);
        return true;
    }

    function allowance(address _owner, address _spender) view public returns (uint256 remaining) {
      return allowed[_owner][_spender];
    }
}

contract MerculetToken is Token {

    string public version = 'v2.0';

    constructor () public Token(10000000000,18,'Merculet','MVP')  {

    }
    
}