Longest Valid Parentheses - Java

Problem

Given a string containing only '(' and ')', return the length of the longest valid (well-formed) parentheses substring.

Approach

This solution uses a stack to store indices of parentheses. It scans the string once and calculates the maximum length of a valid parentheses substring.

Time Complexity

O(n)

Space Complexity

O(n)

How to Run

javac Solution.java
java Solution