Count set bits in an integer OR Brian Kernighan's algorithm

 Brian Kernighan's algorithm

·        We generally use this algorithm to find the number of set bits present in binary numbers.


·        If we subtract a number by 1 and do it bitwise & with itself (n & (n-1)), we unset the rightmost set bit. If we do n & (n-1) in a loop and count the number of times the loop executes, we get the set bit count. 

·        The beauty of this solution is the number of times it loops is equal to the number of set bits in a given integer.

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