InterviewBit Problems   K DISTANCE : Unsolved

About the K DISTANCE : Unsolved category (1)
Input second is not even balanced.(problem is solvable but can't use balanced tree property) (1)
Please provide a better description of the question,stating where a-b<=B means Mod of a-b or not (1)
The expected output is not clear,the question states that a should be ancestor of b (1)