3
0 0 0 0 0 0 9 0 7 
0 0 0 4 2 0 1 8 0 
0 0 0 7 0 5 0 2 6 
1 0 0 9 0 4 0 0 0 
0 5 0 0 0 0 0 4 0 
0 0 0 5 0 7 0 0 9 
9 2 0 1 0 8 0 0 0 
0 3 4 0 5 9 0 0 0 
5 0 7 0 0 0 0 0 0 
