You are given a string composed entirely of ‘(’ and ‘)’ characters. Your goal is to identify the longest contiguous segment (substring) within this string that represents a “well-formed” or “valid” sequence of parentheses.
A substring is considered valid if:
Every opening parenthesis ‘(’ has a corresponding closing parenthesis ‘)’.
The pairs of parentheses are correctly nested.
Return the length of this longest valid substring.
Constraints:
s.length
You are given a string composed entirely of ‘(’ and ‘)’ characters. Your goal is to identify the longest contiguous segment (substring) within this string that represents a “well-formed” or “valid” sequence of parentheses.
A substring is considered valid if:
Every opening parenthesis ‘(’ has a corresponding closing parenthesis ‘)’.
The pairs of parentheses are correctly nested.
Return the length of this longest valid substring.
Constraints:
s.length