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Longest Valid Parentheses

Given a string that contains the characters '(' and ')', find the length of the longest valid parentheses substring.

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Statement

Given a string that contains the characters '(' and ')', find the length of the longest valid parentheses substring.

Example

Let’s look at the image below:

g array ( ( )

The longest valid parentheses substring in "(()" is "()", which has a length of 2.

Sample input

s = "(()"

Expected output

2

Try it yourself

#include <iostream>
#include <string>
using namespace std;
int LongestValidParentheses(string s) {
    // TODO: Write - Your - Code
    return -1;
}

Solution

We can solve this problem with two passes over the input string. As we traverse the string from left to right, we count the number of left parentheses (left) ...

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