Make three strings equal

String

44.6% acceptance

Feb 25, 2026

322

You are given three strings: s1, s2, and s3. In one operation you can choose one of these strings and delete its rightmost character. Note that you cannot completely empty a string. Return the minimum number of operations required to make the strings equal. If it is impossible to make them equal, return -1.

Solution

Rust

Time O(n)

Space O(1)

LeetCode

solution.rs

impl Solution {
  pub fn find_minimum_operations(s1: String, s2: String, s3: String) -> i32 {
    let s1 = s1.as_bytes();
    let s2 = s2.as_bytes();
    let s3 = s3.as_bytes();
    // Find length of longest common prefix of all three
    let min_len = s1.len().min(s2.len()).min(s3.len());
    let mut common = 0;
    while common < min_len && s1[common] == s2[common] && s1[common] == s3[common] {
      common += 1;
    }
    if common == 0 { return -1; }
    (s1.len() + s2.len() + s3.len() - 3 * common) as i32
  }
}