8 9
 0  0  0  4  0  2  0  0
-1 -1 -1 -1 -1 -1  0 -1
 0  4  0  3  0  0  0 -1
 0  2  5  1  0  6  0 -1
 0 -1 -1 -1  0  0 12 -1
 0 10 -5  1 -1  0  0 -1
-1 -1 -1  0  0  6  0  1
 0 -1 20  0 -1  0 -1  0
-1 -1  0  15 0  0 -1 99