10
-2 -1 -2 1
-2 1 -1 1
-1 1 0 2
0 2 1 1
1 1 2 1
2 1 2 -1
2 -1 1 -1
1 -1 0 -2
0 -2 -1 -1
-1 -1 -2 -1
0 0 -1 1 1 1
1 2 3