leetcode 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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其实很简单的题目，但是刚开始想歪了，一直往按位与，异或，取反的方向想了。

就拿11来说，就是得到其2进制的过程我们就可以得到有几个1.这个时候我们回忆一下，如何得到一个数的二进制的，就是连除，然后倒着把余数连起来的过程就是了。

class Solution {
public:
    int hammingWeight(uint32_t n) {
        int count=1,r=0;
        if(n<2) return n;
        while(n/2!=0){
            r=n%2;
            count+=r;
            n/=2;
            
        }
        return count;
        }
        
    
};