【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.

计算给出的整数中二进制的1的数量。

对HammingWeight进行相关拓展。

C++:

 1 class Solution {
 2 public:
 3     int hammingWeight(uint32_t n) {
 4         int cnt=0;
 5         while(n!=0)
 6         {
 7             cnt+=n&1; //not cnt=cnt+n&1  because + is prior than &, and & than +=
 8             n=n>>1;
 9         }
10         return cnt;
11     }
12 };

Python:

1 class Solution:
2     # @param n, an integer
3     # @return an integer
4     def hammingWeight(self, n):
5         cnt=0;
6         while n !=0:
7             cnt+=n&1
8             n=n>>1
9         return cnt