What test is it?

This test help me.
7 10
1 2
1 3
1 4
5 6
5 7
8 9
8 10
8 11
12 13
12 14

Edited by author 04.02.2009 17:56

2 3
1 2
1 3
1 4

impossible

Thanks! It really helped me a lot on WA7!
Actually, it was because I used an array color[100], but I forgot to set them to -1!
It would be very hard to find that out without your help...

this test helped me