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 {

    static int[] array=new int[0];
    static int j=0;
    public static void main(String[] args) {
        Scanner sc=new Scanner(System.in);
        int n=sc.nextInt();
        sc.nextLine();
        String a=sc.nextLine();
        String[] str=a.split("");
        for(int i=0;i<n;i++){
            int x=Integer.parseInt(str[i]);
            if(x==4){
                array(3);
                array(2);
                array(2);
            }
            else if(x==6){
                array(5);
                array(3);
            }
            else if(x==8){
                array(7);
                array(2);
                array(2);
                array(2);
            }
            else if(x==9){
                array(7);
                array(3);
                array(3);
                array(2);
            }
            else if((x%2==0||x%3==0||x%5==0||x%7==0)&&x!=0){
                array(x);
            }
        }
        sort(array);
        for(int i=0;i<array.length;i++){
            System.out.print(array[i]);
        }
        System.out.println("");
    }
    public static void array(int x){
        int[] copy=new int[j+1];
        for(int i=0;i<array.length;i++){
            copy[i]=array[i];
        }
        j++;
        copy[j-1]=x;
        array=copy;
    }
    public static void sort(int[] a){
        for(int i=0;i<a.length-1;i++){
            for(int k=i+1;k<a.length;k++){
                if(a[k]>a[i]){
                    int temp=a[i];
                    a[i]=a[k];
                    a[k]=temp;
                }
            }
        }
        array=a;
    }
    
    
}

  			  				 	 	  				  		 		 		