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 Main {

    public static void main(String[] args) throws IOException {

        BufferedReader bf=new BufferedReader(new InputStreamReader(System.in));
        int n=Integer.parseInt(bf.readLine());
        char a[]=bf.readLine().toCharArray();
        int nums[]=new int[10];
    
         for(int i=0;i<n;i++){
              if(Integer.parseInt(a[i]+"")==0){nums[0]++;}
             if(Integer.parseInt(a[i]+"")==2){nums[2]++;}
              if(Integer.parseInt(a[i]+"")==3){nums[3]++;}
               if(Integer.parseInt(a[i]+"")==4){nums[2]+=2;nums[3]++;}
                if(Integer.parseInt(a[i]+"")==5){nums[5]++;}
                 if(Integer.parseInt(a[i]+"")==6){nums[3]+=1;nums[5]++;}///
                  if(Integer.parseInt(a[i]+"")==7){nums[7]++;}
                   if(Integer.parseInt(a[i]+"")==8){nums[2]+=3;nums[7]++;}
                      
                    if(Integer.parseInt(a[i]+"")==9){nums[2]++;nums[3]+=2;nums[7]++;}
         }
         for(int i=7;i>=2;i--){
         for(int j=0;j<nums[i];j++){
             System.out.print(i);
         }
         }
      
    }
    
 
}
