Drazil is playing a math game with Varda.

Let's define <image> for positive integer x as a product of factorials of its digits. For example, <image>.

First, they choose a decimal number a consisting of n digits that contains at least one digit larger than 1. This number may possibly start with leading zeroes. Then they should find maximum positive number x satisfying following two conditions:

1. x doesn't contain neither digit 0 nor digit 1.

2. <image> = <image>.

Help friends find such number.

Input

The first line contains an integer n (1 ≤ n ≤ 15) — the number of digits in a.

The second line contains n digits of a. There is at least one digit in a that is larger than 1. Number a may possibly contain leading zeroes.

Output

Output a maximum possible integer satisfying the conditions above. There should be no zeroes and ones in this number decimal representation.

Examples

Input

4
1234


Output

33222


Input

3
555


Output

555

Note

In the first case, <image>
import java.util.*;
public class _515C {
    public static void main(String []args) {
        Scanner sc=new Scanner(System.in);
        int n=sc.nextInt();
        String a=sc.next();
        String c[]={" "," ","2","3","322","5","53","7","7222","7332"};
        String rest=" ";
        for(int i=0;i<n;i++) {
            rest+=c[a.charAt(i)-'0'];
        }
        char ans[]=rest.toCharArray();
        Arrays.sort(ans);
        for(int i=(ans.length-1);i>=0;i--)
            System.out.printf("%c",ans[i]);
    }
}