191. Number of 1 Bits

Write a function that takes an unsigned integer and returns the number of '1' bits it has (also known as the Hamming weight).


Note: x & (x-1) clears the least significant 1.


def hammingWeight(n: int) -> int:
       
    count = 0
   
    while n > 0:
        n = n & (n-1)
        count += 1
       
    return count

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