Replace elements with greatest element on right side

Array

72.0% acceptance

Feb 25, 2026

2844

267

Given an array arr, replace every element in that array with the greatest element among the elements to its right, and replace the last element with -1. After doing so, return the array.

Solution

Rust

Time O(n)

Space O(1)

LeetCode

solution.rs

impl Solution {
  pub fn replace_elements(mut arr: Vec<i32>) -> Vec<i32> {
    let n = arr.len();
    let mut max_right = -1i32;
    for i in (0..n).rev() {
      let cur = arr[i];
      arr[i] = max_right;
      max_right = max_right.max(cur);
    }
    arr
  }
}