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.Scanner;


public class Main {
	public static void main(String args[]) {
		Scanner cin = new Scanner(System.in);
	
		int length = cin.nextInt();
		cin.nextLine();
        String number = cin.nextLine();
//        System.out.println("number: " + number);
        int[] count = new int[10];
        for (int i = 0; i < length; i++) {
        	if (number.charAt(i) == '2') {
        		count[2]++;
        	}
        	else if (number.charAt(i) == '3') {
        		count[3]++;
        	}
        	else if (number.charAt(i) == '4') {
        		count[2]+=2;
        		count[3]++;
        	}
        	else if (number.charAt(i) == '5') {
        		count[5]++;
       		}
       		else if (number.charAt(i) == '6') {
       			count[3]++;
       			count[5]++;
       		}
       		else if (number.charAt(i) == '7') {
       			count[7]++;
        	}
        	else if (number.charAt(i) == '8') {
       			count[2]+=3;
       			count[7]++;
       		}
       		else if (number.charAt(i) == '9') {
       			count[2]++;
       			count[3]+=2;
       			count[7]++;
        	}
        }
       	
        for (int i = count.length - 1; i > 1; i--) {
       		while (count[i] > 0) {
       			System.out.print(i);
       			count[i]--;
       		}
       	}
       	System.out.println();
        cin.close();
	}
}

	 		   		  		 	   	 	     	 		