I’ve written a Su Doku solver in Haskell. At the moment you need an interactive Haskell console like Hugs or GHCi to do anything with it, and I’m tempted to keep it that way so as not to spoil the fun too much for manual solvers. On the other hand, I’m also tempted to hook it up to a web interface, maybe with the ability to provide hints and suggestions rather than outright solutions.

I think Haskell is a pretty natural choice for solvers like this one, which are based on simple traversal of a search tree (with a few optimising and validating steps along the way). Most of the functions are pretty small. This time around, I started getting heavily into list comprehensions. The points-free fetish seems to be wearing off at last…

See the Times Su Doku page for information about Su Doku.