function solution(record) {
    var answer = [];
    
    var user_table = {}
    record.map(function(data){
        data = data.split(" ");
        if( data[0] == "Leave" ) return;
        user_table[ data[1] ] = data[2];
    });
    var act;
    var nm;
    
    record.map(function(data){
        data = data.split(" ");

        if( data[0] == "Enter" ) act="들어왔습니다.";
        if( data[0] == "Leave" ) act="나갔습니다.";
        if( data[0] == "Change" ) return;
        nm = user_table[ data[1] ];
        answer.push( `${nm}님이 ${act}` )
    });
    return answer;
}