[wolfgke]

> I wrote a sudoku solver in my first year of college using some heuristsics and some sort of branch-and-cut algorithm, in java.

What class of cutting planes did you use in your B&C algorithm (full disclure: I do my PhD on cutting planes, thus I'm interested)?

[ant6n]

I mean branch-and-bound - i.e. just reject when solution becomes infeasible and back-track. No cutting planes in first year college. ;)

I think the heuristics may have been based on selecting cells that had the least possible solutions, in order to quickly 'zoom in' on the areas where you can quickly prune infeasible solutions.