Valid palindrome iv

Two Pointers String

75.6% acceptance

Mar 31, 2026

111

You are given a 0-indexed string s consisting of only lowercase English letters. In one operation, you can change any character of s to any other character. Return true if you can make s a palindrome after performing exactly one or two operations, or return false otherwise.

Solution

Rust

Time O(n)

Space O(1)

LeetCode

solution.rs

impl Solution {
  pub fn make_palindrome(s: String) -> bool {
    let bytes = s.as_bytes();
    let n = bytes.len();
    let mut mismatches = 0;
    let mut l = 0;
    let mut r = n - 1;
    while l < r {
      if bytes[l] != bytes[r] {
        mismatches += 1;
        if mismatches > 2 {
          return false;
        }
      }
      l += 1;
      r -= 1;
    }
    true
  }
}