pragma solidity ^0.4.8;

contract Token {
  
    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);
}
contract StandardToken is Token {
    function transfer(address _to, uint256 _value) public returns (bool success) {
        require(balances[msg.sender] >= _value);
        balances[msg.sender] -= _value;
        balances[_to] += _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);
        balances[_to] += _value;
        balances[_from] -= _value;
        allowed[_from][msg.sender] -= _value;
        emit Transfer(_from, _to, _value);
        return true;
    }
   
    function balanceOf(address _owner) public constant returns (uint256 balance) {
        return balances[_owner];
    }
   
    function approve(address _spender, uint256 _value) public returns (bool success)   
    {
        allowed[msg.sender][_spender] = _value;
        emit Approval(msg.sender, _spender, _value);
        return true;
    }
    
    function allowance(address _owner, address _spender) public constant returns (uint256 remaining) {
      return allowed[_owner][_spender];
    }

    mapping (address => uint256) balances;
    mapping (address => mapping (address => uint256)) allowed;
}

contract HJGX is StandardToken {
   
    string public name;                  
    uint8 public decimals;                
    string public symbol;                 
    string public version = '1.0';      

    constructor(uint256 _initialAmount, string _tokenName, uint8 _decimalUnits, string _tokenSymbol) public {
        balances[msg.sender] = _initialAmount; 
        totalSupply = _initialAmount;         
        name = _tokenName;                  
        decimals = _decimalUnits;          
        symbol = _tokenSymbol;             
    }
   
    function approveAndCall(address _spender, uint256 _value, bytes _extraData) public returns (bool success) {
        allowed[msg.sender][_spender] = _value;
        emit Approval(msg.sender, _spender, _value);

        require(_spender.call(bytes4(bytes32(keccak256("receiveApproval(address,uint256,address,bytes)"))), msg.sender, _value, this, _extraData));
        return true;
    }
}