백준 3986 좋은 단어(JAVA)

문제 설명

https://www.acmicpc.net/problem/3986

 

풀이과정

스택을 이용해서 풀이한다.

 

정답코드

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));
        BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));

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

        int result = 0;
        for (int i = 0; i < N; i++) {
            String s = br.readLine();

            Stack<String> stack = new Stack<>();
            for (int j = 0; j < s.length(); j++) {
                if (stack.isEmpty()) {
                    stack.push(s.substring(j, j + 1));
                } else {
                    if (stack.peek().equals(s.substring(j, j + 1))) {
                        stack.pop();
                    } else {
                        stack.push(s.substring(j, j + 1));
                    }
                }
            }

            if (stack.isEmpty()) {
                result++;
            }
        }

        bw.write(String.valueOf(result));
        bw.flush();
    }
}