Square polyominos were obfuscated a long time ago
using regexps. The program won as most creative
of the OPC3
. If you remove the printing code that shows the progression of the search, it is relatively fast too. The trick used is to fold the board to make the problem unidimensional. I used it as a obfuscation trick to use regexp but it can be used as well as a performance boost.
BTW: there are 12 pentominoes, not eleven. Finding all of them is already quite a challenge.
You should check a Knuth paper
that talks about dancing links to solve polyominoes problems and the N-Queens problem. The best book about about polyominos was written by Samuel Golomb and aptly
stefp -- check out TeXmacs