Inputs: 13
Comment: END algorithm

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

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

0 7
3 11
4 9
5 8
10 12

2 9
3 10
6 8
11 12

1 3
2 5
4 6
8 10
9 11

0 1
3 7
8 9
10 11

1 2
3 4
5 8
6 7
9 10

1 3
2 4
5 6
7 8

2 3
4 5
6 7
8 9

3 4
5 6