[JAVA ]프로그래머스 - 오픈채팅방(openChatRoom) 42888

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

코딩테스트 연습 - 오픈채팅방 | 프로그래머스

 

public class Solution {


public String[] solution(String[] record) {
        String[] answer;       
        //반환배열 길이(인풋된 record 길이에서 change동작은 제외한 길이)
        int answerSize=0;
        //동작유형배열
        String[] operTypeArr = {"Enter","Leave","Change"};
        //아이디,닉네임 맵 
        Map<String,String> uidMap = new HashMap<String,String>();
        //동작, 반환값 맵 
        Map<String,String> answerMap = new HashMap<String,String>();
        answerMap.put("Enter", "님이 들어왔습니다.");
        answerMap.put("Leave", "님이 나갔습니다.");
        // 입력받은 값을 2차원 배열에 담습니다
        String[][] record2 = new String[record.length][3];

        for(int i=0; i<record.length; i++) {
            record2[i] = record[i].split(" ");
        }

        //아이디,닉네임맵에 정보를 담고 닉네임 변경을 반영합니다.
        for(int j=0; j<record2.length; j++) {   
            if(record2[j][0].equals("Enter")) {
                uidMap.put(record2[j][1], record2[j][2]);
                answerSize++;
            }else if(record2[j][0].equals("Change")) {
                uidMap.replace(record2[j][1], record2[j][2]);
            }else {
                answerSize++;               
            }
        }
        
        answer = new String[answerSize];

        //입력정보에서  uidMap에서 uid값을 키로 닉네임정보를 맵에서 불러 옵니다.(change동작은 제외)
        //record 배열과 answer배열의 길이가 다르기때문에 배열 인덱스를 매칭시켜줄 변수를 정의합니다.
        int answerIdx = 0;
        for(int i=0; i<record2.length; i++) {
            String operType = record2[i][0];
            if(!operType.equals(operTypeArr[2])) {
                answer[answerIdx]=uidMap.get(record2[i][1])+answerMap.get(operType);
                answerIdx++;
            }
        }
        return answer;
    }
}