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.io.*;
import java.util.*;
public class drazilandfactorial {
public static void main(String[] args) throws Exception
{
    Scanner sc=new Scanner(System.in);
    int n=sc.nextInt();
    String s=sc.next();
    int[] a=new int[10];
    int[] b=new int[10];
    for(int i=0;i<n;i++)
    {
        int z=s.charAt(i)-'0';
        a[z]++;
    }
    b[2]=a[2];
    b[3]=a[3];
    b[5]=a[5];
    b[7]=a[7];
    b[2]+=2*a[4];
    b[3]+=a[4];
    b[5]+=a[6];
    b[3]+=a[6];
    b[7]+=a[8];
    b[2]+=(3*a[8]);
    b[7]+=a[9];
    b[3]+=2*a[9];
    b[2]+=1*a[9];
    for(int i=9;i>=2;i--)
    {
        for(int j=0;j<b[i];j++)
        {
            System.out.print(i+"");
        }
    }
}
}
