Why there is error ?in one test case

#1
#2

hi @gagz23 can you explain your approach a bit? And do tell what is the error message.

#3
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test case1 is nnot accepted it shows wrong answer

#5

hi @gagz23 there’s a very neat trick to this question. If you observe carefully, you have to take steps of 2. The binary representation of the number also consists powers of 2 only. So the answer is actually the number of set bits (number of 1s in the binary representation) in the number. Do try this approach!