461. Hamming Distance - Easy

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.

 

bit manipulation

time = O(# of bits), space = O(1)

class Solution {
    public int hammingDistance(int x, int y) {
        int cnt = 0;
        for(int i = x ^ y; i != 0; i >>= 1) {
            cnt += i & 1;
        }
        return cnt;
    }
}