[못풀었다/프로그래머스] 불량사용자

function solution(user_id, banned_id) {
    const set = new Set()
    const banIdCopy = banned_id.slice()
    const selected = Array.from({length:user_id.length},()=>false)
    
    const isChecked = (bannedId,userId) => {
     if(bannedId.length!==userId.length) return false;
     else 
     {for(let i=0;i<bannedId.length;i++){
            if(bannedId[i]!=='*'&&bannedId[i]!==userId[i]){
                return false
            }
        }}
        return true;
    }
    //bannedId가 끝날때까지 dfs로 돌면서, 이미 사용한 user_id는 지워줘야함.
    const dfs = (banIdCopy, arr = []) => {
        if (banIdCopy.length === 0) {
            set.add(arr.sort().join(','));
        } else {
            for (let i = 0; i < user_id.length; i++) {
                if (selected[i]) {
                    continue;
                }
                if (isChecked(banIdCopy[0],user_id[i])) {
                    selected[i] = true;
                    dfs(banIdCopy.slice(1), [...arr, user_id[i]]);
                    selected[i] = false;
                }
            }
        }
    };
    dfs(banIdCopy)
    return set.size
    
}