Check if all characters have equal number of occurrences

Hash Table String Counting

79.4% acceptance

Feb 25, 2026

1035

Given a string s, return true if s is a good string, or false otherwise. A string s is good if all the characters that appear in s have the same number of occurrences (i.e., the same frequency).

Solution

Rust

Time O(n)

Space O(1)

LeetCode

solution.rs

impl Solution {
  pub fn are_occurrences_equal(s: String) -> bool {
    let mut freq = [0; 26];
    for b in s.bytes() {
      freq[(b - b'a') as usize] += 1;
    }
    let target = freq.iter().filter(|&&x| x > 0).next().unwrap();
    freq.iter().filter(|&&x| x > 0).all(|x| x == target)
  }
}