461 - Hamming Distance

2020/07/18

Problem

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.
Accepted

Solution

Solution 1:

class Solution:
    def hammingDistance(self, x: int, y: int) -> int:
        z = x ^ y
        s = 0
        while z:
            s += z & 1
            z = z >> 1
        return s

Solution 2: t & (t - 1)

class Solution:
    def hammingDistance(self, x: int, y: int) -> int:
        z = x ^ y
        s = 0
        while z:

            s += 1
            z = z & (z - 1)

        return s