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 pr1 {
    public static void main(String args[]) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int ar[]={1,2,3,223,5,53,7,7222,7332};
        StringBuilder sb=new StringBuilder();
        String s=sc.next();
        for(int i=0;i<n;i++)
        {
            char ch=s.charAt(i);
            if(ch=='0')
                ch='1';
            if(ch=='1')
                continue;
            int val=Integer.parseInt(""+ch);
            sb.append(ar[val-1]);
        }
        String s2=sb.toString();
        char arr[]=s2.toCharArray();
        Arrays.sort(arr);
        StringBuilder ans=new StringBuilder();
        for(char ch:arr)
        {
            ans.append(ch);
        }ans.reverse();
        System.out.println(ans.toString());
    }
}