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- Turn off all lights in a ring-shaped palace 12 answers
My friend told me this riddle, and I have been struggling for weeks to find the answer.
You are in a circular room, the size doesn't matter. Meaning, the room could be 5 feet in circumference or billions of miles in circumference. There are lights periodically, but evenly placed in the room with switches that can turn them on and off, however, the lights originally start off in an either on or off position, in a random order. You can walk anywhere in the room, but you can only see the 4 or 5 lights in front of you (you can't see every light in the room at the same time). You don't need to find how many lights are in the room, but, what is the METHOD for finding out how many lights there are?
You can't break the lights or spit on walls or take off your clothes to mark your location in any way possible. Also, the fact that they are lights is NOT important. It's important that it's a binary code that can be a random sequence of 1's and 0's. It's also NOT important that it's a room, but it is important that it is circular. For example, it could be a table with pennies periodically placed around the edges with them faced on heads or tails. However, it's easier to imagine it as a room. Since it's binary, you also have to assume that there is any possible combination, and the method of just walking around the whole room and counting and turning on all the lights won't work, because it's possible to believe that you have reached the end when you reach a random stretch of lights that are already turned on.
I think it's pretty difficult.