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Light Switches

ReasoningMedium~15 min· Brain Teasers
Problem

The Problem

You're in a room with 3 light switches, all off. Each controls one of 3 light bulbs in another room (you can't see the bulbs from the switches). You can flip the switches however you want, but you can only enter the bulb room ONCE.

How do you determine which switch controls which bulb?