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 Drazil {
    public static void main(String[] args) {
       Scanner input = new Scanner(System.in);
       int a = input.nextInt();
       int[] arr = new int[100000];
       String str = (input.next()).substring(0,a);
       char[] l = str.toCharArray();
       int t=0;

       for(int i=0;i<a;i++){
           if(l[i]=='1' || l[i]=='0')continue;
           else if(l[i]=='2') arr[t++]=2;
           else if(l[i]=='3') arr[t++]=3;
           else if(l[i]=='4'){
               arr[t++]=2;
               arr[t++]=2;
               arr[t++]=3;
           }
           else if(l[i]=='5') arr[t++]=5;
           else if(l[i]=='6'){ arr[t++]=5; arr[t++]=3;}
           else if(l[i]=='7') arr[t++]=7;
           else if(l[i]=='8')
           {
               arr[t++]=7;
               arr[t++]=2;
               arr[t++]=2;
               arr[t++]=2;
           }
           else if(l[i]=='9'){
               arr[t++]=7;
               arr[t++]=2;
               arr[t++]=3;
               arr[t++]=3;
           }

       }
        Arrays.sort(arr);

        for(int i= arr.length-1;i>=arr.length-t;i--)
        {
            System.out.print(arr[i]);
        }

    }
}
