Total hamming distance

Array Math Bit Manipulation

54.6% acceptance

Jan 13, 2026

2301

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.

Solution

Rust

Time O(n)

Space O(1)

LeetCode

solution.rs

impl Solution {
  pub fn total_hamming_distance(nums: Vec<i32>) -> i32 {
    let mut total = 0;
    let n = nums.len();
    
    for bit in 0..32 {
      let ones = nums.iter().filter(|&&num| (num & (1 << bit)) != 0).count();
      total += (ones * (n - ones)) as i32;
    }
    
    total
  }
}