Ok let's give it another try
My 3 switches riddle was:
Turn 1 on, wait 5 minutes, then 1 off and 2 on.
Then go check, if the lamp is:
off and warm = 1
on = 2
off and cold = 3
My idea for the 4 switches was:
1 on, wait 5 minutes
2 on and 1 off, wait 5 minutes
3 on and 2 off, then go check, if the lamp is:
off and a little bit warm = 1
off and very warm = 2
on = 3
off and cold = 4
But there was a better solution, so maybe this:
1 and 2 on, wait 5 minutes
1 still on, 2 off and 3 on, then go check very quick
on and very warm even the surrounding things = 1
off and warm = 2
on but surrounding things are still cold = 3
off and cold = 4
If this isn't correct you may tell me.
![Wink :wink:](./images/smilies/icon_wink.gif)