Hamming Distance

1. Problem Description

The Hamming distance between two integers is the number of positions at which their corresponding binary bits are different.

Given two integers x and y, calculate the Hamming distance between them.

2. Approach

1. Approach 1
   • XOR: same is 0, different is 1
   • AND: for example, to take the 3rd bit, use &0001000
2. Approach 2
   1. XOR directly
   2. Then count the number of 1s

3. Implementation

3.1. XOR Each Bit

package main

func hammingDistance(x int, y int) int {
	bit := 1
	count := 0
	for i := 0; i < 32; i++ {
		numx := x & bit
		numy := y & bit
		if numx^numy != 0 {
			count += 1
		}
		bit <<= 1
	}
	return count
}

3.2. Count After XOR

func hammingDistance(x int, y int) int {
    res := 0

    xor := x ^ y
    bit := 1
    for i := 0; i < 32; i++ {
        if xor & bit != 0 {
            res++
        }
        bit <<= 1
    }

    return res
}

4. References

• Hamming Distance - Hamming Distance - LeetCode