contract Controlled {
    /// @notice The address of the controller is the only address that can call
    ///  a function with this modifier
    modifier onlyController { require(msg.sender == controller); _; }

    address public controller;

    function Controlled() public { controller = msg.sender;}

    /// @notice Changes the controller of the contract
    /// @param _newController The new controller of the contract
    function changeController(address _newController) onlyController public {
        controller = _newController;
    }
}
function changeController(address _newController) onlyController public {
    controller = _newController;
}

/// @notice Changes the controller of the contract
/// @param _newController The new controller of the contract