4 4
0 2 0 1
0 6 1 8
0 4 8 3
0 4 3 0
2 12 0 9
6 8 9 4
4 8 4 10
4 5 10 0
12 3 0 11
8 11 11 7
8 4 7 8
5 1 8 0
6 0 3 0
11 0 6 3
4 0 3 7
1 0 7 0
