4 3
0 1
0 2
0 3
4 3
0 1
0 2
1 3
4 6
0 1
0 2
0 3
1 2
1 3
2 3
4 4
0 1
0 2
1 2
2 3
4 5
0 1
0 2
0 3
1 2
1 3