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.*;

public class cf292_3
{
	public static void main(String args[])
	{
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		String s = sc.next();
		s = s.replace("0","");
		s = s.replace("1","");
		s = s.replace("4","322");
		s = s.replace("6","53");
		s = s.replace("8","7222");
		s = s.replace("9","7332");
		char s1[] = s.toCharArray();
		Arrays.sort(s1);
		for(int i=1;i<=s1.length;i++)
		{
			System.out.print(s1[s1.length-i]);
		}
	}
} 