5
9
3
1
9
2
8
9
7
3
1
2
4
5
8
9
1
7
6
5
2
3
9
5
2
5
6
3
2
8
9
8
3
"Make each day your masterpiece." — John Wooden
"Make each day your masterpiece." — John Wooden
Donald Knuth's "Algorithm X" with dancing links solves exact cover problems — of which Sudoku is a special case.
Donald Knuth's "Algorithm X" with dancing links solves exact cover problems — of which Sudoku is a special case.