hard 9×9 Set 3 Grid Puzzle
2
5
9
1
8
3
2
9
1
8
4
5
3
1
4
7
2
3
6
1
4
4
7
3
2
6
1
6
8
4
1
8
5
4
9
7
3
6
1
5
3
9
7