SUDOKU
The objective is to fill a 9×9 grid so that each column, each row, and each of the
nine 3×3 boxes (also called blocks or regions) contains the digits from 1 to 9 only
one time each. The puzzle setter provides a partially completed grid.
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
4
2
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
9
3
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
5
7
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
7
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
4
6
1
2
3
4
5
6
7
8
9
3
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
1
1
2
3
4
5
6
7
8
9
8
2
9
1
2
3
4
5
6
7
8
9
8
9
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
4
6
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
1
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
5
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
8
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
4
1
2
3
4
5
6
7
8
9
3
1
2
3
4
5
6
7
8
9
7
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
2