(백준/자바) 1764번 문제 : 듣보잡

1764번: 듣보잡 (acmicpc.net)

1764번: 듣보잡

흠.. HashMap과 List를 사용해 엄청 간단하게 구현했는데 시간초과가 나왔다 

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.StringTokenizer;

public class Solution {
    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        StringBuilder sb = new StringBuilder();
    	StringTokenizer st = new StringTokenizer(br.readLine());
        int N = Integer.parseInt(st.nextToken());
        int M = Integer.parseInt(st.nextToken());
        Map <Integer,String> lmap = new HashMap<>();
        List <String> key = new ArrayList<>();
        for(int i=0;i<N;i++) {
        	lmap.put(i,br.readLine());
        }
       for(int i=0;i<M;i++) {
    	   String str = br.readLine();
    	   if(lmap.containsValue(str))
    		   key.add(str);
       }
       Collections.sort(key);
       for(String s : key) {
    	   sb.append(s+"\n");
       }
        System.out.println(key.size()+"\n"+sb);
    }
}

아 ㅡㅡ ㅋㅋ 진짜 짜증나네

key.size()를 sysout에서 뽑아서 시간초과난 거임 ㅡㅡ 하

sb에 담아놓았으면 좋았을 것을....

--->은 아니었음 !!!!

Map을 key값으로 찾아야 빠름 !!!!!!!!!!!!!!!!!!

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.StringTokenizer;

public class Solution {
    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        StringBuilder sb = new StringBuilder();
    	StringTokenizer st = new StringTokenizer(br.readLine());
        int N = Integer.parseInt(st.nextToken());
        int M = Integer.parseInt(st.nextToken());
        Map <String,Integer> lmap = new HashMap<>();
        List <String> list = new ArrayList<>();
        for(int i=0;i<N;i++) {
        	lmap.put(br.readLine(),0);
        }
        for(int i=0;i<M;i++) {
        	String str = br.readLine();
        	if(lmap.containsKey(str))
        		list.add(str);
        }

        Collections.sort(list);
        for(int i=0;i<list.size();i++) {
        	sb.append(list.get(i)+"\n");
        }
        System.out.println(list.size()+"\n"+sb);
    }
}