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 Drazil{
    public static void main(String args[]){
        Scanner scan = new Scanner(System.in);
        
        int numDigits = scan.nextInt();
        
        int[] digits = new int[10];
        
        char[] characters = scan.next().toCharArray();
        
        for(char c : characters){
            if(c == '2'){
                digits[2]++;
            }else if(c == '3'){
                digits[3]++;
            }else if(c == '4'){
                digits[2] += 2;
                digits[3]++;
            }else if(c == '5'){
                digits[5]++;
            }else if(c == '6'){
                digits[5]++;
                digits[3]++;
            }else if(c == '7'){
                digits[7]++;
            }else if(c == '8'){
                digits[2] += 3;
                digits[7]++;
            }else if(c == '9'){
                digits[7]++;
                digits[3]+=2;
                digits[2]++;
            }
        }
        
        for(int i=9;i>1;i--){
            while(digits[i] > 0){
                System.out.print(i);
                digits[i]--;
            }
        }
    }
}