JAVA

maximum valid parentheses

public static void main(String[] args) {
    String s="))((())";
    String finalString="";
    for(int i=0;i<s.length();i++){

         if (s.charAt(i) == '('&& s.charAt(i+1) == ')') {
         String ss= s.substring(i, i+2);
         finalString=finalString+ss;
        // System.out.println(ss);
         }

    }
    System.out.println(finalString.length());
}