longest-balanced-substring-i

You are given a string s consisting of lowercase English letters.

A substring of s is called balanced if all distinct characters in the substring appear the same number of times.

Return the length of the longest balanced substring of s.

Example 1:

Input: s = "abbac"

Output: 4

Explanation:

The longest balanced substring is "abba" because both distinct characters 'a' and 'b' each appear exactly 2 times.

Example 2:

Input: s = "zzabccy"

Output: 4

Explanation:

The longest balanced substring is "zabc" because the distinct characters 'z', 'a', 'b', and 'c' each appear exactly 1 time.​​​​​​​

Example 3:

Input: s = "aba"

Output: 2

Explanation:

​​​​​​​One of the longest balanced substrings is "ab" because both distinct characters 'a' and 'b' each appear exactly 1 time. Another longest balanced substring is "ba".

Constraints:

• 1 <= s.length <= 1000


• s consists of lowercase English letters.