3
2 0 0 7 0
4 1 0 3 1 4 0 6 0
3 0 -1 3 2 5 0

0

7
8
3

0 -1
0 0
1 0
4 0
5 0
6 0
7 0

2 0 -1 1 0 1
2 0 0 1 0 1
2 1 0 4 0 1
3 1 0 3 1 4 0 1
3 1 0 3 2 5 0 1
2 4 0 5 0 2
2 5 0 6 0 2
2 6 0 7 0 1
