Sum of number and its reverse

Math Enumeration

49.3% acceptance

Feb 25, 2026

279

306

Given a non-negative integer num, return true if num can be expressed as the sum of any non-negative integer and its reverse, or false otherwise. *

Solution

Rust

Time O(n²)

Space O(1)

LeetCode

solution.rs

impl Solution {
  pub fn sum_of_number_and_reverse(num: i32) -> bool {
    for k in 0..=num {
      let mut x = k;
      let mut rev = 0;
      while x > 0 {
        rev = rev * 10 + x % 10;
        x /= 10;
      }
      if k + rev == num {
        return true;
      }
    }
    false
  }
}