Sudoku solver. Uses abstract theory of colourable graphs, so the code could be generalized to other graph-colouring problems.

ant

Create a data file in the boards/ directory named myboard.gb

For example:

3
0 9 2 5 6 0 0 0 0
0 0 3 0 2 7 0 6 0
6 0 0 0 0 0 2 7 9
0 0 8 0 0 0 4 2 3
0 4 0 0 3 2 0 5 0
0 3 6 0 5 8 0 0 0
3 2 0 8 0 0 0 0 6
1 0 0 2 0 0 9 0 5
4 0 0 6 0 9 3 0 0

The first line is normally 3, the number of values across a cell.

The rest of the lines specify the given values, with 0 for an unknown value.

ant run -Dboard=myboard.gb

The program will find every possible solution (typically unique, in a correctly-designed puzzle.)