Maximum product of two digits

Math Sorting

69.3% acceptance

Feb 25, 2026

You are given a positive integer n. Return the maximum product of any two digits in n. Note: You may use the same digit twice if it appears more than once in n.

Solution

Rust

Time O(n)

Space O(n)

LeetCode

solution.rs

impl Solution {
  pub fn max_product(n: i32) -> i32 {
    let mut digits: Vec<i32> = Vec::new();
    let mut x = n;
    while x > 0 {
      digits.push(x % 10);
      x /= 10;
    }
    digits.sort_unstable_by(|a, b| b.cmp(a));
    digits[0] * digits[1]
  }
}