LeetCode 416 Hamming Distance（位运算）

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.

题目大意：求两个数二进制不相同的位数。

解题思路：先用异或运算求出总的不相同的位数z，然后再计算z的二进制中有几个1。

代码如下：

int hammingDistance(int x, int y) {
    int z = x ^ y;
    int count = 0;
    while(z){
        z = z & (z - 1);//消除最低位的1
        count++;
    }
    return count;
}