I am trying to solve this problem.....

http://mirror.codeforces.com/problemset/problem/281/B

but i am continuously getting WA in a case.i check that case in pc's compiler it gives me correct output.i have copied my code and check it in custom test(codeforce compiler) and it gives different result. i can't found my mistake and can't found the solution :( here is my code http://mirror.codeforces.com/contest/281/submission/17562664

Plz anyone help me...