I love the game. (It's just called "Set.") It's available in better game and toy stores around the USA. I think it came out in about 1993.

As a code review, I'd make two minor bits of feedback. Update: artist has revised the article in consideration of these tips.

(1) Single-letter identifiers are very hard to search for, and very easy to accidentally recycle. Try to use natural noun-like words instead of single letter symbols. $count may be a count but what is $C? What is $p, $q and $r, and why would I want their $sum?

(2) With such obtuse variable names, comments are even more important. You've got no comments at all (except for some debugging aids you've disabled). Strategy in comments, tactics in code. Write your algorithm in plain English in comments, and then translate that algorithm into specific code and data with Perl syntax.

As it is, the __DATA__ section and the writeup are far more descriptive than anything else in the code. Without these, it's a black box.

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