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Number of 1 Bits - InterviewBit Solution

Problem: Number of 1 Bits

Problem Description:

Given a number, count the number of set bits.


The 32-bit integer 11 has binary representation


so the function should return 3

Solution Approach:

To solve this problem we can keep dividing it by 2, whenever the remainder is 1, that means there is a set bit, so increment the count.

Space & Time Complexity:

Time Complexity: O(logN)

- Since each time we are diving the number by 2.

Space Complexity: O(1)


Code in C++