题目：

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

For example, the 32-bit integer ’11' has binary representation 00000000000000000000000000001011, so the function should return 3.

答案：

求一个数字二进制形式时的汉明权重，也就是里面有多少个1

1 class Solution { 2 public: 3     int hammingWeight(uint32_t n) { 4         int count=0; 5         for(int i=0;i<32;i++){ 6             if(n&1==1){ 7                 count++; 8             } 9             n=n>>1;10         }11         return count;12     }13 };