case 7 failed
expected: 8
 got: 9
input:
9 34
1 6
3 7
4 6
7 8
4 8
5 9
1 5
3 6
7 9
1 4
5 8
8 9
5 6
5 7
3 5
6 7
2 9
2 3
1 9
3 8
2 4
2 6
1 7
2 8
1 2
6 8
4 9
3 4
4 5
1 8
2 5
3 9
1 3
6 9