[leetcode] Number of 1 Bits

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.

Special thanks to @ts for adding this problem and creating all test cases.

class Solution {
    int hammingWeight(uint32_t n) {
        int ans = 0;
        for(size_t i = 0; i < 32; i++){
            if(n & (0x00000001 << i)){
        return ans;


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