[백준/Java] 1764번 듣보잡

-Code

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.*;

public class BOJ1764 {
    public static void main(String[] args) throws IOException {
        BufferedReader br = 
                new BufferedReader(new InputStreamReader(System.in));
        StringTokenizer st = new StringTokenizer(br.readLine());
        
        int n = Integer.parseInt(st.nextToken());
        int m = Integer.parseInt(st.nextToken());
        
        Map<String, Boolean> nameMap = new HashMap<>();
        for (int i = 0; i < n; i++) {
            String name = br.readLine();
            nameMap.put(name, true);
        }
        
        int cnt = 0;
        List<String> answerName = new ArrayList<>();
        for (int i = 0; i < m; i++) {
            String checkName = br.readLine();
            // 값이 없으면 false로 명단에 있으면 저장
            if (nameMap.getOrDefault(checkName, false)) {
                cnt++;
                answerName.add(checkName);
            }
        }

        br.close();
		// 사전 순 정렬
        Collections.sort(answerName);
        System.out.println(cnt);
        for (String name : answerName) {
            System.out.println(name);
        }
    }
}