xkcd 1313 by simulated annealing in Clojure

Like any red-blooded American, I find regex golf fascinating. The idea, to paraphrase the comic strip, is to find a regular expression that matches all members of a group of related terms, but not any members of a different group. The hover text on the strip suggests a regex that matches all winning presidents.

Peter Norvig went to town on this, first clarifying the problem and then building an algorithm to search for the shortest solution that matches all mainstream presidential candidates who eventually won, but not such candidates who never won. (So Perot, Nader, Anderson et al don't figure …

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