>>I only strongly disagree about recursion being the most popular genre here. IMO, the most popular genre is date calculation. Just try to ask for code which, for example, lists months which have five fridays in a given year, and start counting the attempts. Somewhere 20 messages down the thread, a "but I can't see how this can be done in one line" should appear.
>
>Speaking of date calculations... A light exercise (that shouldn't take too long to work out on paper with a little bit of math):
>Typically Friday the 13th is considered unlucky. Is there such a thing as a year without any Friday the 13ths, and if not, what is the minimum number of Friday the 13ths? What is the maximum number of Friday the 13ths?

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