Check if All Characters Have Equal Number of Occurrences

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.
SOLUTION:
class Solution:
    def areOccurrencesEqual(self, s: str) -> bool:
        ctr = {}
        for c in s:
            ctr[c] = ctr.get(c, 0) + 1
        return len(set(ctr.values())) == 1

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