48 - Lighten Up
Three switches at the top of the stairs outside a cellar door each operate one of three light inside the cellar.
If you can only go through the door once, how can you tell which switch operates which light?
Three switches at the top of the stairs outside a cellar door each operate one of three light inside the cellar.
If you can only go through the door once, how can you tell which switch operates which light?