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>
/**
 * Created by mahshid on 3/16/15.
 */
import  java.util.*;
public class Main {
    public static void main(String[] args){
        Scanner input = new Scanner(System.in);
        int n = input.nextInt();
        String a = input.next();
        int[] arr = count(a);
        System.out.println();
        for(int i = 3; i >=0; i--)
        {
            for(int j = 0; j < arr[i]; j++){
               if(i == 0)
                    System.out.print(2);
                if(i == 1)
                    System.out.print(3);
                if(i == 2)
                    System.out.print(5);
                if(i == 3)
                    System.out.print(7);
            }
        }
    }
    public static int[] count(String s ){
        int[] ret = new int[4];
        for(int i = 0;i < s.length(); i++){
            switch(s.charAt(i)){
                case '2':
                {
                    ret[0]++;
                    break;
                }
                case '3' :
                {
                    ret[1]++;
                    break;
                }
                case '4' :
                {
                    ret[1]++;
                    ret[0] += 2;
                    break;
                }
                case '5':
                {
                    ret[2]++;
                    break;
                }
                case '6':
                {
                    ret[1]++;
                    ret[2]++;
                    break;
                }
                case '7':
                {
                    ret[3]++;
                    break;
                }
                case '8':
                {
                    ret[3]++;
                    ret[0] += 3;
                    break;
                }
                case '9':
                {

                    ret[3]++;
                    ret[0] ++;
                    ret[1]+= 2;
                    break;
                }
            }
        }
        return ret;
    }

}
