...and each single pole, single throw switch controls one 60-watt incandescent light bulb in a table reading lamp in each of 3 rooms down the hallway. The lamps operate properly, and they are plugged in. There is a one-to-one correspondence between lights and switches. From the place where the switches are, nothing can be seen of the 3 rooms, since the hallway turns right and then left.  The doors to the rooms have no windows, and you have to open the door to see whether the light is on inside each room.  You are only allowed to walk down the hall one time, and you can go into each of the 3 rooms in turn only once, one at a time.  Your challenge is to flip the light switches any way you want, and then you may go to inspect the rooms, but you must then be able to say which of the switches control each rooms' light.

How would you accomplish this feat?

Yaaaay!