Programmers

(LV.2) 2019 KAKAO BLIND RECRUITMENT - 오픈채팅방 (opens new window)

function solution(record) {
    let answer = [];
    const map = new Map();

    answer = record
        .reduce((acc, cur) => {
            const [cmd, uid, name] = cur.split(" ");
            if (cmd === "Enter") {
                map.set(uid, name);
                acc.push(`${uid} 님이 들어왔습니다.`);
            } else if (cmd === "Leave") {
                acc.push(`${uid} 님이 나갔습니다.`);
            } else if (cmd === "Change") {
                map.set(uid, name);
            }
            return acc;
        }, [])
        .map((r) => {
            const [id] = r.split(" ");
            return r.replace(id + " ", map.get(id));
        });

    return answer;
}