pragma solidity 0.4.24;

contract Ownable {

    address public owner;

    constructor() public {
        owner = msg.sender;
    }

    function setOwner(address _owner) public onlyOwner {
        owner = _owner;
    }

    modifier onlyOwner {
        require(msg.sender == owner);
        _;
    }

}

contract Vault is Ownable { 

    function () public payable {

    }

    function getBalance() public view returns (uint) {
        return address(this).balance;
    }

    function withdraw(uint amount) public onlyOwner {
        require(address(this).balance >= amount);
        owner.transfer(amount);
    }

    function withdrawAll() public onlyOwner {
        withdraw(address(this).balance);
    }
}