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.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.lang.reflect.Array;
import java.util.ArrayList;
import java.util.Collections;

public class Main {
    public static void main(String args[]) throws IOException{
        BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
        in.readLine();
        String str = in.readLine();
        ArrayList<Integer> res = new ArrayList<>();
        for(int i=0; i<str.length(); i++){
            convert(res, str.charAt(i) - '0');
        }
        
        Collections.sort(res);
        for(int i=res.size() - 1; i>=0; i--){
            System.out.print(res.get(i));
        }
    }
    
    private static void convert(ArrayList<Integer> res, int a){
        if(a==2||a==3||a==5||a==7) {
            res.add(a);
            return;
        }
        if(a==4) {
            res.add(3);
            res.add(2);
            res.add(2);
            return;
        }
        if(a==6){
            res.add(5);
            res.add(3);
            return;
        }
        if(a==8){
            res.add(7);
            res.add(2);
            res.add(2);
            res.add(2);
            return;
        }
        
        if(a==9){
            res.add(7);
            res.add(3);
            res.add(3);
            res.add(2);
        }
        
    }
}
