Why did you got wa on test 3 ? I'm having the same problem... :(

try this test:
1
16
2 3 4 5 1 2 3 4 5 2 2 2 2 2 2 0

answer, it is clear, NO, but this test helped me when I had WA#3

I had WA#3, too.
That test helped me.
1
5
0 0 0 0 0

It's NO, of course! )
Edited by author 16.03.2006 16:39

Edited by author 16.03.2006 16:40

Or maybe it is

1
5
0 3 4 5 3

Answer: NO

>>Or maybe it is
>>
>>1
>>5
>>0 3 4 5 3
>>
>>Answer: NO

ASK, thank you. If there is a loop in graph that can be entered by branch from nodes earlier in list then loop nodes than some naive algorithms can fail on this test.

By the way, why not to add the tag GRAPH THEORY to this problem? It not that deep though.