#2981
Find Longest Special Substring That Occurs Thrice I
specialist · 690 · lc medium +30 · verified · 61.9% accepted · 727 likes · top 62%
Description
You are given a string s consisting of lowercase English letters.
A string is special if it consists of a single repeated character, e.g., "ddd" and "f" are special, but "abc" is not.
Return the length of the longest special substring of s that appears at least three times, or -1 if none exists.
A substring is a contiguous non-empty sequence of characters within a string.
Example 1:
Input: s = "aaaa"
Output: 2
Explanation: The longest special substring which occurs thrice is "aa": substrings "aaaa", "aaaa", and "aaaa".
It can be shown that the maximum length achievable is 2.
Example 2:
Input: s = "abcdef"
Output: -1
Explanation: There exists no special substring which occurs at least thrice. Hence return -1.
Example 3:
Input: s = "abcaba"
Output: 1
Explanation: The longest special substring which occurs thrice is "a": substrings "abcaba", "abcaba", and "abcaba".
It can be shown that the maximum length achievable is 1.
Code
1
2
3