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.*;

public class code {
    public static void main(String args[]){
        Scanner scan = new Scanner(System.in);
        String n = scan.nextLine();
        String s = scan.nextLine();
        List<Character> v = new ArrayList();
        for(int i=0;i<s.length();i++){
            char x = s.charAt(i);
            if(x=='4'){
                v.add('3');
                v.add('2');
                v.add('2');
            }
            else if(x=='6'){
                v.add('5');
                v.add('3');
            }
            else if(x=='8'){
                v.add('7');
                v.add('2');
                v.add('2');
                v.add('2');
            }
            else if(x=='9'){
                v.add('7');
                v.add('3');
                v.add('3');
                v.add('2');
            }
            else if(x!='1' && x!='0'){
                v.add(x);
            }
        }
        //System.out.println(v);
        Collections.sort(v,Collections.reverseOrder());
        String ans = "";
        for(int i=0;i<v.size();i++){
            ans += v.get(i);
        }
        System.out.println(ans);
    }
}
