python leetcode461 汉明距离

one day a cannon or one week five cannons

leetcode 461 hamming distance 

(Source) The Hamming
distance between two integers is the number of positions at which the corresponding bits are different.

Given two integers 

x

 and 

y

,
calculate the Hamming distance.

Note: 

0 ≤ 

x

, 

y

 < 231.

Example:

Input: x = 1, y = 4

Output: 2

Explanation:
1   (0 0 0 1)
4   (0 1 0 0)
↑   ↑

The above arrows point to positions where the corresponding bits are different.

知识点注意：x^y是异或运算，不同为1，相同为0，bin()的结果是01字符串，求结果01字符串中的'1'字符的个数，就是hamming distance。

class Solution(object):
def hammingDistance(self, x, y):
"""
:type x: int
:type y: int
:rtype: int
"""
return bin(x ^ y).count('1')