Dart Coding Essentials: 101

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

Example 1:

Input: s = "(()"
Output: 2
Explanation: The longest valid parentheses substring is "()".

Example 2:

Input: s = ")()())"
Output: 4
Explanation: The longest valid parentheses substring is "()()".

Example 3:

Input: s = ""
Output: 0

void main() {
  
  List<String> temp = longestValidParentheses("(()");
  print("Output ${temp.length}");
  print("The longest valid parentheses substring is ${temp.first} and ${temp.last}");
  }


List<String> longestValidParentheses(String s) {
 
  List<String> temp = List.empty(growable:true);
      
        for(int i=0;i< (s.length-1);i++){
            if(s[i] == "("){
                if(s[i+1] == ")"){
                  print(s[i]);
                  print(s[i+1]);
                    temp.add(s[i]);
                    temp.add(s[i+1]);
                }
            }
        }
        return temp;
    }