[프로그래머스] 소수 찾기 JavaScript DFS 순열

https://school.programmers.co.kr/learn/courses/30/lessons/42839

//소수판별
function isPrime(num){
    if (num <= 1) return false
    for(let i = 2; i <= Math.sqrt(num); i++){
        if(num%i===0) return false
    }
    return true
}
function solution(numbers) {
    let visited = new Array(numbers.length).fill(0);
    let answer = [];
  	//순열 구하기
    const dfs = (result)=>{
        if(result != "" && isPrime(parseInt(result)))
            answer.push(parseInt(result))
        for (let i=0; i<numbers.length; i++){
            if (!visited[i]){
                visited[i]=1;
                dfs(result+numbers[i]);
                visited[i]=0;
            }
        }
    }
    dfs("");
  	// 중복제거후 개수 리턴 
    return new Set(answer).size
}