WA in KINGCON

I was trying to solve this simple problem but unfortunately my answer isnt coming right KINGCON Problem - CodeChef. Here is my code 1G9qVs - Online C++ Compiler & Debugging Tool - Ideone.com . I am trying to implment the standard algorithm for articulation points.

Hey anyone please look into it , i have tried my level best and i cant find any bugs.

Admin since no one is able to help me and i have tried so many times could u please point my mistake.Or send me the test cases for this question only to my email id.
I request you since only then will i be able to improve.

did u get some testcases??since i m also getting wrong answer…can u plz help me… Here is my solution CodeChef: Practical coding for everyone

here is another modified try CodeChef: Practical coding for everyone Could anyone please help me