contract IERC20 {
    function totalSupply() public view returns (uint);

    function balanceOf(address owner) public view returns (uint);

    function allowance(address owner, address spender) public view returns (uint);

    function transfer(address to, uint value) public returns (bool);

    function approve(address spender, uint value) public returns (bool);

    function transferFrom(address from, address to, uint value) public returns (bool);

    // ERC20 Optional
    function name() public view returns (string);
    function symbol() public view returns (string);
    function decimals() public view returns (uint8);

    event Transfer(
      address indexed from,
      address indexed to,
      uint value
    );

    event Approval(
      address indexed owner,
      address indexed spender,
      uint value
    );
}
/**
 * @title ERC20 interface
 * @dev see https://github.com/ethereum/EIPs/issues/20
 */
function name() public view returns (string);

// ERC20 Optional