It seems for each subtree,the optimal moves is aaaaaaababababa or bbbbbbbbabababab (i.e. alice makes x consecutive moves then bob and alice make alternative moves or bob makes y consecutive moves then alice and bob make alternative moves)(I'm not clear, but seems correct). If this conclusion is correct,we can compute sg[id][con_moves] using dynamic programing for each con_moves we can divide them to x moves to left subtree,y moves to right subtree(x+y==con_moves)

I have got 7 denial of judgement now,but when I submit other problems it is ok,what's wrong?

http://mirror.codeforces.com/gym/100125

I submit gym neerc 2011 F flight,and wait for a long time....then it returns judgement fail?

http://mirror.codeforces.com/gym/100134

I have found there are some unexpected characters such as spaces or tal in the input file. I'm sure my code will run correct on small test cases,but wa on test 1 30ms.my code will run much more than 30ms on big test.. So hope admin can check it..