In this Leetcode Total Hamming Distance problem solution, The Hamming distance between two integers is the number of positions at which the corresponding bits are different.

Given an integer array nums, return the sum of Hamming distances between all the pairs of the integers in nums.

Leetcode Total Hamming Distance problem solution


Problem solution in Python.

class Solution(object):
    def totalHammingDistance(self, nums):
        result=0
        for i in range(32):
            count1=0
            count0=0
            for j in nums:
                if (j>>i)&1:
                    count1 +=1
                else:
                    count0 +=1
                    
            result +=(count1*count0)
        return result

Problem solution in Java.

public int totalHammingDistance(int[] nums) {
        int count = 0;
        for (int i = 0; i < 32; i++) {
            int zeros = 0;
            int ones = 0;
            
            for (int z = 0; z < nums.length; z++) {
                if ((nums[z] & 1) == 1) ones++;
                else zeros++;
                
                nums[z] >>= 1;
            }
            
            count += ones * zeros;
        }
        
        return count;
    }
}


Problem solution in C++.

class Solution {
public:
    int totalHammingDistance(vector<int>& nums) {
        int count=0;
        
        for(int i=0;i<31;i++){
            int x=1<<i;
            int tmp=0;
            for(int j=0;j<nums.size();j++){
                if((x&nums[j])==0) tmp++;
            }
            count+=tmp*(nums.size()-tmp);
        }
        return count;
    }
};