[LeetCode] 461. Hamming Distance

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.

Thought process:
Count the number of 1 bit in x XOR y.

Solution:

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public class Solution {
    public int hammingDistance(int x, int y) {
        return Integer.bitCount(x ^ y);
    }
}

Time complexity:
Say the larger number has n bits. The overall time complexity is O(n).
Location: San Jose, CA, USA

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