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).
For example, the 32-bit integer ’11' has binary representation 00000000000000000000000000001011,
so the function should return 3.
Credits:
Special thanks to @ts for adding this problem and creating all test cases.
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