【leetcode】Number of 1 Bits

题目描述：

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.

解题思路：

简单的除就可以了。

class Solution:
# @param n, an integer
# @return an integer
def hammingWeight(self, n):
res = 0
while n != 0:
if n % 2 != 0:
res += 1
n /=2
return res