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