461. Hamming Distance

The Hamming distance
(https://en.wikipedia.org/wiki/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.

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.

code:
class Solution {
 func hammingDistance(_ x: Int, _ y: Int) -> Int {
    var cnt = 0;
    var res = 0;
    res = x ^ y;
    print(res)
    while(res != 0){
        cnt = cnt + 1;
        res = res&(res - 1);
        }
    return cnt;
    }

}

based on swift 3