3
4 7
0 1
0 2
0 2
0 3
1 3
2 3
3 3
4 6
0 1
0 2
0 3
1 2
1 3
2 3
6 10
0 3
1 2
4 0
5 1
4 4
2 3
1 3
3 2
1 4
5 1