Brain Teaser
There are two rooms seperated by a long hallway, with closed doors in each room.
In one room there are three light switches, in the other room there are three lightbulbs.
HOW do you determine which lightswitch correlates to which lightbulb if you can only walk down the hallway once.
No you can't see from one room to the other and this is not a play on words.
Give up? . . . check the answer.