Could you help me the spot the possible error in code logic which is making the test cases to fail.
overHaapyNumbers code logic
Hey i think there is some problem with test cases in java.Let me check the test cases.Till then try running your code on leetcode.
Link-https://leetcode.com/problems/happy-number/#:~:text=Happy%20Number%20-%20LeetCode&text=Write%20an%20algorithm%20to%20determine,number%20n%20is%20"happy".&text=Those%20numbers%20for%20which%20this,number%2C%20and%20False%20if%20not.
Hi Mohit,
This is working fine on Leet Code.
Also for the unique character string question, test cases are not designed to meet every possible scenario where code may fail. Please get that updated as well.
Thanks 
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