2
0 -1  0 -1 -1  0 -2
0 -1  0  0 -1  0 -2
0
3 2 1
-1  0 -2
-1  0 -1
-1  0  0
0 -1  0 -2 -1  0 -1 2
0 -1  0  0 -1  0 -1 1
