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.*;
import java.io.*;
 
public class cp{

    public static void main(String[] args) {
    
    	Scanner sc = new Scanner();

    	HashMap<Integer,String> h = new HashMap<>();

    		
    	h.put(2,"2");
    	h.put(3,"3");
    	h.put(4,"322");
    	h.put(5,"5");
    	h.put(6,"53");
    	h.put(7,"7");
    	h.put(8,"7222");
    	h.put(9,"7332");
    	
    	StringBuilder ans = new StringBuilder("");
    	int n = sc.nextInt();

    	char ar[] = sc.nextLine().toCharArray();

    	for(int i=0;i<n;i++)
    	{
    		if(h.containsKey(ar[i]-'0'))
    		{
    			ans.append(h.get(ar[i]-'0'));
    		}
    	}	
    	char qw[] = ans.toString().toCharArray();
    	// out.println(ans);
    	Arrays.sort(qw);

    	for(int i=qw.length-1;i>=0;i--)
    		out.print(qw[i]);
        out.close();
    }

    static  PrintWriter out=new PrintWriter(System.out);
    static class Scanner {
        BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
        StringTokenizer st=new StringTokenizer("");
        String nextLine() {
            while (!st.hasMoreTokens())
                try { 
                                        st=new StringTokenizer(br.readLine());                             
                                } catch (IOException e) {}
            return st.nextToken();
        }     
        int nextInt() {
            return Integer.parseInt(nextLine());
        }
        Double nextDouble() {
            return Double.parseDouble(nextLine());
        }
        long nextLong() {
            return Long.parseLong(nextLine());
        }
    }
}
 