Anonymous Monk gives some code he's started so you are a bit unfair I think.

As someone who creates exercises for a living, this is exactly the kind of exercise I would create. I also note the absence of "real world" indicators in the question, again leading toward an abstract problem that someone would not have occur "in the wild".

No, I'll stand by my assessment. Homework, with some of the work done, but missing some essential piece. Nothing that should be answered, because the student should go back to the teacher for answers, not rely on the virtual brain of the monastery.

-- Randal L. Schwartz, Perl hacker
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