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.Arrays;
import java.util.Scanner;


public class Main {
	public static void main(String args[]){
		int n;
		String str;
		Scanner s = new Scanner(System.in);
		n = s.nextInt();
		str = s.next();
		
		str = str.replaceAll("0", "");
		str = str.replaceAll("1", "");
		
		str = str.replaceAll("4", "223");
		str = str.replaceAll("6", "35");
		str = str.replaceAll("8", "2227");
		str = str.replaceAll("9", "2337");
		// 922 338 332227
		
		char chs[] = str.toCharArray();
		Arrays.sort(chs);
		for(int i = chs.length - 1; i >=0; i--){
			System.out.print(chs[i]);
		}
		System.out.println();
		
		
		
		
	}
}
