LeetCode OJ：Number of 1 Bits（比特1的位数）

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.

计算一个数字的二进制表示中含有的bit1的个数，简单的右移而已，代码如下所示：

 class Solution {
 public:
     int hammingWeight(uint32_t n) {
         if(n == ) return ;
         int ret = ;
         while(n != ){
             if(n &  == ){
                 ret++;
             }
             n >>= ;
         }
         return ret;
     }
 };