[힌트 문제1-3] 스택

백준 9012번 스택과 괄호

 

나는 Scanner 와 Stack으로 품

import java.util.Scanner;
import java.util.Stack;

// Press Shift twice to open the Search Everywhere dialog and type `show whitespaces`,
// then press Enter. You can now see whitespace characters in your code.
public class Main {

    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);

        int T = in.nextInt();

        for (int i = 0; i < T; i++) {
            System.out.println(solve(in.next()));
        }

    }

    public static String solve(String s) {
        Stack<Character> stack = new Stack<>();

        for (int i = 0; i < s.length(); i++) {
            char c = s.charAt(i);
            if (c == '(') {
                stack.push(c);
            } else if (stack.empty()) {
                return "NO";
            } else {
                stack.pop();
            }
        }

        if (stack.empty()) {
            return "YES";
        } else {
            return "NO";
        }
    }

}