12
-2 2 -2 3
-1 1 -1 4
0 0 0 5
1 0 1 5
2 1 2 4
3 2 3 3
0 0 1 0
-1 1 2 1
-2 2 3 2
-2 3 3 3
-1 4 2 4
0 5 1 5