Tests for this problem are weak (e.g. see here: http://codeforces.ru/blog/entry/2920#comment-59153 )

I think you can try to add the following tests:
5 1
1 0
1 2
2 1
3 0
3 2

5 2
1 0
1 2
2 1
3 0
3 2

3 1
0 0
0 1
0 2

3 1
0 0
1 0
2 0


3 2
0 0
0 1
0 2

3 2
0 0
1 0
2 0

Edited by author 22.10.2011 22:51

All AC solutions pass all of your tests. :) So I will not add them. But I have added a test from discussion at Codeforces and some more tests of similar structure.