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 test
{
public static void main(String[] args)
{
 
Scanner sc=new Scanner(System.in);
int n=sc.nextInt();
String s=sc.next();
ArrayList<Integer> ar=new ArrayList<Integer>();
for(int i=0;i<s.length();i++)
{
    int yy=s.charAt(i)-'0';
    
    if(yy==2)
    ar.add(2);
    if(yy==3)
    {
        ar.add(3);
    }
    if(yy==4)
    {
        ar.add(3);        ar.add(2);ar.add(2);
    }if(yy==5)
    {
        ar.add(5);
    }if(yy==6)
    {
        ar.add(3);ar.add(5);
    }if(yy==7)
    {
        ar.add(7);
    }
    if(yy==8)
    {
        ar.add(2);
         ar.add(2);
          ar.add(2);
          ar.add(7);
    }
    if(yy==9)
    {
        ar.add(7);
        ar.add(2);
        ar.add(3);ar.add(3);
    }
}
Collections.sort(ar,Collections.reverseOrder());
for(int i=0;i<ar.size();i++)
System.out.print(ar.get(i));}}


