백준알고리즘 1764번 듣보잡

백준알고리즘

https://www.acmicpc.net/problem/1764

import java.util.Arrays;
import java.util.HashSet;
import java.util.Scanner;
import java.util.Set;

public class Main {
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        int N = scan.nextInt();
        int M = Integer.parseInt(scan.nextLine().trim());
        
        Set<String> nSet = new HashSet<String>();
        String[] mSet = new String[M];
        Set<String> result = new HashSet<String>();
        
        for(int i=0; i<N; i++) {
            String input = scan.nextLine().trim();
            nSet.add(input);
        }
        
        for(int i=0; i<M; i++) {
            String input = scan.nextLine().trim();
            mSet[i] = input;
        }
        
        for(int i=0; i<M; i++) {
            if(nSet.contains(mSet[i]) == true) {
                result.add(mSet[i]);
            }
        }
        
        String[] tmp=result.toArray(new String[result.size()]);
        Arrays.sort(tmp);   //오름차순 정렬
        System.out.println(tmp.length); //길이 출력
        for(int i=0; i<tmp.length;i++)
            System.out.println(tmp[i]); //듣보잡 출력
    }
}