4055. Longest Balanced Substring I

Medium

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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.

// Add your C++ solution here

class Solution {
    public int longestBalanced(String s) {
        int n = s.length();
        int res = 0;
        for (int i = 0; i < n; i++) {
            int freq[] = new int[26];
            for (int j = i; j < n; j++) {
                freq[s.charAt(j) - 'a']++;
                int flag = 1;
                int maxi = 0;
                for (int ele : freq)
                    maxi = Math.max(maxi, ele);
                for (int ele : freq) {
                    if (ele > 0 && ele != maxi)
                        flag = 0;
                }
                if (flag == 1)
                    res = Math.max(res, j - i + 1);
            }
        }
        return res;
    }
}