백준 9012번 괄호 JAVA

링크텍스트

import java.io.*;
import java.util.*;

public class Main{

    public static void main(String[] args) throws IOException{
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    StringBuilder sb = new StringBuilder(); 

    Stack<Character> s = new Stack<>();

    int n = Integer.parseInt(br.readLine());

    for(int i=0;i<n;i++){

        boolean right = true;
        String ss = br.readLine();

            for(int j=0;j<ss.length();j++){
                char c = ss.charAt(j); 

                    if(c=='('){
                        s.push(c);
                    }if(s.isEmpty()&&c==')'){
                        right =false;
                        break;
                    }if(!s.isEmpty()&&c==')'){
                        s.pop();
                    }
            }
            if(right && s.isEmpty()){
               sb.append("YES"+"\n");
            }else 
                sb.append("NO"+"\n");

            s.clear();
    }
        System.out.print(sb);
    }
}