contract ERC20Interface {
    // Get the total token supply
    function totalSupply() public constant returns (uint256 tS);
 
    // Get the account balance of another account with address _owner
    function balanceOf(address _owner) constant public returns (uint256 balance);
 
    // Send _value amount of tokens to address _to
    function transfer(address _to, uint256 _value) public returns (bool success);
 
    // Send _value amount of tokens from address _from to address _to
    function transferFrom(address _from, address _to, uint256 _value) public returns (bool success);
 
    // Allow _spender to withdraw from your account, multiple times, up to the _value amount.
    // If this function is called again it overwrites the current allowance with _value.
    // this function is required for some DEX functionality
    function approve(address _spender, uint256 _value) public returns (bool success);
 
    // Returns the amount which _spender is still allowed to withdraw from _owner
    function allowance(address _owner, address _spender) constant public returns (uint256 remaining);

    // Used for burning excess tokens after ICO.
    function burnExcess(uint256 _value) public returns (bool success);
 
    // Used for burning excess tokens after ICO.
    function transferWithFee(address _to, uint256 _value, uint256 _fee) public returns (bool success);

    // Triggered when tokens are transferred.
    event Transfer(address indexed _from, address indexed _to, uint256 _value);
 
    // Triggered whenever approve(address _spender, uint256 _value) is called.
    event Approval(address indexed _owner, address indexed _spender, uint256 _value);

    // Triggered whenever tokens are destroyed
    event Burn(address indexed from, uint256 value);

    // Triggered when tokens are transferred.
    event TransferWithFee(address indexed _from, address indexed _to, uint256 _value, uint256 _fee);

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

// Allow _spender to withdraw from your account, multiple times, up to the _value amount.
// If this function is called again it overwrites the current allowance with _value.
// this function is required for some DEX functionality