Keycode

You are required to solve the secret coded positions of four keys in order to start the engines of your spacecraft. There are 595, 665 different combinations! In order to assist you in your task you may fire test lasers to deduce the correct keycode. When you believe you have solved the problems set the four keys in the keycode positions. If you are correct the engines will start. If you are wrong you are doomed as the keycode panel will shut for ever.