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;

/**
 * Created by Ruslan on 17.02.2015.
 */
public class Prob43 {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int [][] mas  = new int[][]{{},
                {}, 
                {0, 1},
                {0, 0, 1},
                {0, 2, 1},
                {0, 0, 0, 0, 1},
                {0, 0, 1, 0, 1},
                {0, 0, 0, 0, 0, 0, 1},
                {0, 3, 0, 0, 0, 0, 1},
                {0, 1, 2, 0, 0, 0, 1}};
        int[] ans = new int[9];
        int n = in.nextInt();
        in.nextLine();
        String s = in.nextLine();
        for (int i = 0; i <s.length(); i++) {
            int k = Integer.parseInt(s.charAt(i)+"");
            for (int j = 0; j < mas[k].length; j++) {
                ans[j] += mas[k][j];
            }
        }
        for (int i = 8; i > 0; i--){
            for (int j = 0; j < ans[i]; j++) {
                System.out.print(i+1);
            }
        }
        System.out.println();
        in.close();
    }
}
