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Practice Longest Valid Parentheses

Read the task, work through the examples, and check your approach against the constraints. Use the original LeetCode task for coding and submissions.

Hard#32
LeetCode Problem

Longest Valid Parentheses

StringDynamic ProgrammingStack

Problem Statement

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

Source: Longest Valid Parentheses on LeetCode. Use the original task for its coding environment and submissions.

Examples

# Example 1

Input
s = "(()"
Output
2

# Example 2

Input
s = ")()())"
Output
4

# Example 3

Input
s = ""
Output
0

Constraints

0 <= s.length <= 3 * 10^4
s[i] is '(', or ')'.

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