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Problem: Longest Valid Parentheses

Explore how to identify the longest valid parentheses substring within a given string. This lesson guides you through using a stack to track indices and calculate substring lengths efficiently, helping you understand stack operations, string traversal, and algorithmic problem-solving in C++.

Statement

Given a string s consisting solely of the characters '(' and ')', determine the length of the longest valid (well-formed) parentheses substring contained within s.

A valid parentheses substring is one in which every opening parenthesis '(' has a corresponding closing parenthesis ')', and the pairs are properly nested.

Constraints:

  • 00 \leq s.length 3×104\leq 3 \times 10^4 ...