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)
   {
      int[] factorial = {0, 1, 2, 6, 24, 120, 720, 5040, 40320, 362880};
      Scanner keyboard = new Scanner(System.in);
      int n = keyboard.nextInt();
      String number = keyboard.next();
      String ans = "";
      int num2 = 0;
      int num3 = 0;
      int num5 = 0;
      int num7 =0;
      for(int i=0;i<n;i++)
      {
         char c = number.charAt(i);
         if(c=='2')
            num2++;
         else if(c=='3')
         {
            num2++;
            num3++;
         }
         else if(c=='4')
         {
            num2+=3;
            num3++;
         }
         else if(c=='5')
         {
            num2+=3;
            num3++;
            num5++;
         }
         else if(c=='6')
         {
            num2+=4;
            num3+=2;
            num5++;
         }
         else if(c=='7')
         {
            num2+=4;
            num3+=2;
            num5++;
            num7++;
         }
         else if(c=='8')
         {
            num2+=7;
            num3+=2;
            num5++;
            num7++;
         }
         else if(c=='9')
         {
            num2+=7;
            num3+=4;
            num5++;
            num7++;
         }
      }
      while(num7>0)
      {
         ans = ans + "7";
         num7--;
         num5--;
         num3-=2;
         num2-=4;
      }
      while(num5>0)
      {
         ans = ans + "5";
         num5--;
         num3--;
         num2-=3;
      }
      while(num3>0)
      {
         ans = ans + "3";
         num3--;
         num2--;
      }
      while(num2>0)
      {
         ans = ans + "2";
         num2--;
      }
      System.out.println(ans);
   }
}
           
        