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Longest Valid Parentheses (hard)

Problem Statement

You are given a string containing just the characters '(' and ')'. Your task is to find the length of the longest valid (well-formed) parentheses substring.

Example 1:

  • Input: "(())"
  • Expected Output: 4
  • Justification: The entire string is a valid parentheses substring.

Example 2:

  • Input: ")()())"
  • Expected Output: 4
  • Justification: The longest valid parentheses substring is "()()".

Example 3:

  • Input: "(()"
  • Expected Output: 2
  • Justification: The longest valid parentheses substring is "()".

Constraints:

  • 0 <= s.length <= 3 * 10<sup>4</sup>
  • s[i] is '(', or ')'.

Try it yourself

Try solving this question here:

Python3
Python3
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