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, return the Hamming distance between them.
Example 1:
Input: x = 1, y = 4
Output: 2
Explanation:
`
1 (0 0 0 1)
4 (0 1 0 0)
↑ ↑
`
The two positions marked with ↑ have different bits.
Example 2:
Input: x = 3, y = 1
Output: 1
0 <= x, y <= 2^31 - 1