2019 KAKAO BLIND RECRUITMENT: 오픈채팅방

https://programmers.co.kr/learn/courses/30/lessons/42888

코딩테스트 연습 - 오픈채팅방

// 자바

import java.util.*;
import java.util.Map.*;
 
class Solution {
    
    public int makeUid(String[] record, Map<String, String> map) {
        int cnt = 0;        
        for(String str : record) {
            String[] temp = str.split(" ");
            if(temp[0].equals("Enter") || temp[0].equals("Change")) { 
                map.put(temp[1], temp[2]); 
            }   
            if(!temp[0].equals("Change")) cnt++;
        }
        return cnt;
    }
    
    public String[] solution(String[] record) {
        Map<String, String> map = new HashMap<>(); 
        
        int size = makeUid(record, map); 
        String[] answer = new String[size];
        int cursor = 0;
        
        for(String str : record) {
            String[] temp = str.split(" ");
            String name = map.get(temp[1]);
            if(temp[0].equals("Enter")) {
                answer[cursor++] = name + "님이 들어왔습니다.";
            } else if(temp[0].equals("Leave")) {
                answer[cursor++] = name + "님이 나갔습니다.";
            }                  
        }
        
        return answer;
    }
}