12.Hamming Distance（汉明距离）

Level：

  Easy

题目描述：

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.

思路分析：

  汉明距离指的是两个数的二进制形式中对应位数值不同的数目。因此我们将两个数相异或，那么异或结果的二进制形式中非零位的个数就是汉明距离。

代码：

class Solution {
    public int hammingDistance(int x, int y) {
        int xor=(x^y);
        int t=1;
        int res=0;
        while(t>0){
            if((xor&t)!=0)
                res++;
            t<<=1;
        }
        return res;
    }
}