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.Scanner;

public class Main{
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        String s = sc.next();
        int[] a = new int[20];
        for(int i=0;i<n;i++){
            int t = s.charAt(i)-'0';
            if(t==2)a[2]++;
            if(t==3){
                a[3]++;
            }
            if(t==4){
                a[2]+=2;
                a[3]++;
            }
            if(t==5){
                a[5]++;
            }
            if(t==6){
                a[3]++;
                a[5]++;
            }
            if(t==7){
                a[7]++;
            }
            if(t==8){
                a[2]+=3;
                a[7]++;
            }
            if(t==9){
                a[2]++;
                a[3]+=2;
                a[7]++;
            }
        }
        for(int i=9;i>1;i--){
            for(int j=0;j<a[i];j++){
                System.out.print(i);
            }
        }
    }
}
  		  					  	 		        	   		