I think that the points about printing an explanation for the results are valid, but I would recommend taking it a step further. Since these teasers have a non-obvious result, I think people would also like to see code that does give the answer that was originally expected. In this case, for instance, how to modify the code so that it prints "1 2 3 4 5". After all, I'm sure we've all experienced the frustration of bugs in our logic; for a newbie the frustration would be worse.

Spacewarp

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