pragma solidity ^0.4.18;
contract Will {

  address public owner;
  address public beneficiary;
  uint256 public deathTimeout = 20 seconds;
  uint256 public lastSignOfLife;

  function Will(address _beneficiary) public{
      owner = msg.sender;
      beneficiary = _beneficiary;
      ImAlive();
  }

  function ImAlive() public {
      require(msg.sender == owner);
      lastSignOfLife = now;
  }

  function withdrawUponDeath() public {
      require(now > lastSignOfLife + deathTimeout);
      beneficiary.transfer(address(this).balance);
  }

  function withdrawWhenAlive(uint256 _amount) public {
      require(owner == msg.sender);//only owner can do this
      msg.sender.transfer(_amount);
  }

  function () payable public {

  }

  function getBalance() public view returns(uint256) {
      return address(this).balance;
  }

}