Sort array by parity

Array Two Pointers Sorting

76.5% acceptance

Feb 25, 2026

5675

156

Given an integer array nums, move all the even integers at the beginning of the array followed by all the odd integers. Return any array that satisfies this condition.

Solution

Rust

Time O(n)

Space O(1)

LeetCode

solution.rs

impl Solution {
  pub fn sort_array_by_parity(mut nums: Vec<i32>) -> Vec<i32> {
    let (mut l, mut r) = (0, nums.len() - 1);
    while l < r {
      if nums[l] % 2 != 0 && nums[r] % 2 == 0 { nums.swap(l, r); }
      if nums[l] % 2 == 0 { l += 1; }
      if nums[r] % 2 != 0 { if r == 0 { break; } r -= 1; }
    }
    nums
  }
}