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Comment by MaysonL | Hacker News Reader

I call BS on Problem 1: it's bait and switch!

The answer to the puzzle #1 is simply totally incorrect: how long the permutations are has nothing to do with whether your name is in any of the boxes in the permutation that the prisoners start with your name.

EDIT: After thinking about, and trying a few small {try 4 boxes) examples, I'm not so sure [i.e. I guess I blew it].

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> The answer to the puzzle #1 is simply totally incorrect: how long the permutations are has nothing to do with whether your name is in any of the boxes in the permutation that the prisoners start with your name.

The answer is correct. Your name has to be in the cycle started with your box, this follows from the fact that permutations are bijections. It is impossible to have something like:

  0->1->2->1

(Because then 1 would be in two boxes at once, which is impossible.)

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