contract ERC20 {

    // ERC Token Standard #223 Interface
    // https://github.com/ethereum/EIPs/issues/223

    string public symbol;
    string public  name;
    uint8 public decimals;

    function transfer(address _to, uint _value, bytes _data) external returns (bool success);

    // approveAndCall
    function approveAndCall(address spender, uint tokens, bytes data) external returns (bool success);

    // ERC Token Standard #20 Interface
    // https://github.com/ethereum/EIPs/blob/master/EIPS/eip-20.md


    function totalSupply() public view returns (uint);
    function balanceOf(address tokenOwner) public view returns (uint balance);
    function allowance(address tokenOwner, address spender) public view returns (uint remaining);
    function transfer(address to, uint tokens) public returns (bool success);
    function approve(address spender, uint tokens) public returns (bool success);
    function transferFrom(address from, address to, uint tokens) public returns (bool success);
    event Transfer(address indexed from, address indexed to, uint tokens);
    event Approval(address indexed tokenOwner, address indexed spender, uint tokens);

    // bulk operations
    function transferBulk(address[] to, uint[] tokens) public;
    function approveBulk(address[] spender, uint[] tokens) public;
}
// ----------------------------------------------------------------------------
function approveAndCall(address spender, uint tokens, bytes data) external returns (bool success);
// approveAndCall