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;

public class Main {
    
    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        int n = Integer.parseInt(br.readLine());
        char[] ar = br.readLine().toCharArray();
        int[] arr = new int[ar.length];
        for(int i=0; i<arr.length; i++){
            arr[i] = ar[i]-'0';
        }
        
        String ans = "";
        for(int i=0; i<n; i++){
            if(arr[i]==6){
                ans = ans + "53";
            }else if(arr[i]==4){
                ans= ans+"322";
            }else if(arr[i]==8){
                ans = ans + "7222";
            }else if(arr[i]==9){
                ans = ans+"7332";
            }
            else if(arr[i]!=0 && arr[i]!=1){
                ans=ans+Integer.toString(arr[i]);
            }
        }
        int[] anus = new int[ans.length()];
        for(int i=0; i<anus.length; i++){
            anus[i] = ans.charAt(i)-'0';
        }
        Arrays.sort(anus);
        for(int i=anus.length-1; i>=0; i--){
            System.out.print(anus[i]);
        }
        System.out.println();
    }
}