I would not ask it as an interview question either, and in fact I dislike interview puzzles unless they are directly related to the task at hand. I did ask this

I would not ask it as an interview question either, and in fact I dislike interview puzzles unless they are directly related to the task at hand. I did ask this student to look at it, though. Without knowing anything about her I thought it might give me at least a little insight into whether I thought she was suited to a CS program, or not. Basically, I was hoping that _she_ would use her own reaction to the puzzle to make that judgment about herself. I know CS isn't really directly related to this kind of toy puzzle, but like I mentioned, because solving it requires systematic thinking along the lines of making a mathematical proof.