The subject test data is too strange

I input:
6
1 10
1 12
2 14
2 23
5 17
5 18
output:
4
3 4 6 5  test is wa#15

I change algorithm ， input again

output
4
3 4 5 6    test is wa #9

but I think both the result are all right, why?



Edited by author 23.12.2008 05:33