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.util.Arrays;
import java.util.HashMap;
public class fibmodified {
    public static void main(String[] args) throws NumberFormatException, IOException{
    BufferedReader br=new BufferedReader (new InputStreamReader(System.in));
    HashMap<Integer,String> arr=new HashMap<Integer,String>();
    arr.put(0,"");
    arr.put(1,"");
    arr.put(2,"2");
    arr.put(3,"3");
    arr.put(4,"322");
    arr.put(5,"5");
    arr.put(6,"53");
    arr.put(7,"7");
    arr.put(8,"7222");
    arr.put(9,"7332");
    int t=Integer.parseInt(br.readLine());
    String str=br.readLine();
    StringBuilder sb=new StringBuilder("");
    for(int j=0;j<t;j++){
    sb.append(arr.get(Character.getNumericValue(str.charAt(j))));
    }
     char[] ch=sb.toString().toCharArray();
     Arrays.sort(ch);
     String s=new StringBuffer(String.valueOf(ch)).reverse().toString();
     System.out.println(s);
    }
}