Leetcode/461.HammingDistance.h at master · bluepp/Leetcode · GitHub

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/*
2016-12-24
bluepp
May the force be with me!

https://leetcode.com/problems/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.
*/

/* 2018/11/01 */

    int hammingDistance(int x, int y) {

        int ret = 0;

        for (int i = 0; i < 32; i++) {
            int bit = 1 << i;

            if ((x & bit) ^ (y & bit)) {
                ret ++;
            }

        }

        return ret;
    }


    int hammingDistance(int x, int y) {

        int ret = 0;
        int exc = x ^ y;

        for (int i = 0; i < 32; i++)
        {
            ret += (exc >> i) & 1;
        }

        return ret;
    }