1941. Check if All Characters Have Equal Number of Occurrences

Posted on In Words count: 1.1k Reading time ≈ 1 mins.

1941. Check if All Characters Have Equal Number of Occurrences

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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).

 

Example 1:

Input: s = "abacbc"
Output: true
Explanation: The characters that appear in s are 'a', 'b', and 'c'. All characters occur 2 times in s.
Example 2:

Input: s = "aaabb"
Output: false
Explanation: The characters that appear in s are 'a' and 'b'.
'a' occurs 3 times while 'b' occurs 2 times, which is not the same number of times.
 

Constraints:

1 <= s.length <= 1000
s consists of lowercase English letters.

Difficulty : Easy

Solution

Use int[26] to store the # of occurrences for each character

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class Solution {
    public boolean areOccurrencesEqual(String s) {
        int[] counts = new int[26];
        char[] array = s.toCharArray();
        for (char c : array) {
            counts[c-'a']++;
        }
        int cnt = counts[array[0] - 'a'];
        for (int i = 0; i < 26; i++) {
            if (counts[i] != 0 && counts[i] != cnt) {
                return false;
            }
        }
        return true;
    }
}