Solves Sudoku by reducing Sudoku to the exact cover problem and using Knuth's Algorithm X. The algorithm is implemented in Python 2.7 using the efficient dancing links technique.

Redirect standard input:

python solver.py < [PATH TO PUZZLE]

Columns are not separated Rows are separated by new lines Unknown values are represented by 0s

Example:

000790050
352008040
000000080
010070004
600301008
900080010
020000000
040500891
080037000