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.Arrays;
import java.util.Scanner;

public class CopyOfA {

    public static void main(String[] args) {

        Scanner input = new Scanner(System.in);

        int n = input.nextInt();

        String b = input.next();
        String output = "";
        for (char c : b.toCharArray()) {
            if (c == '4') {
                output+="322";
            }
            else if (c == '6') {
                output+="53";
            }
            else if (c == '8') {
                output+="7222";
            }
            else if (c == '9') {
                output+="7332";
            }
            else if(c == '0' || c == '1') {
                continue;
            }
            else
                output +=c;
        }
        char[] chars = output.toCharArray();
        Arrays.sort(chars);
        String sorted = new String(chars);
        System.out.println(new StringBuilder(sorted).reverse().toString());

    }
    


}
