Description
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.
解题:
此题目为汉明距离,题中定义汉明距离为2个整数的相同二进制位的数字不同的个数和。
理解好英文,就很容易想到和二进制以及异或有关。
本题的解题思路是:根据十进制转换二进制的原理,在一步步转换过程中对每位数字进行异或,当此位置形同时为0 ,不相同时为1,计数自动加1.
有的可能觉得用到Python的内置函数bin()比较简单,其实代码看似少了,但是效率没有此算法好。
class Solution(object):
def hammingDistance(self, x, y):
m = 0
while x or y:
m += (x%2)^(y%2)
x //=2
y //=2
return m