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 Problem {

	public static void main(String[] args) {
		Scanner keyBoard = new Scanner(System.in);
		
		int n = keyBoard.nextInt();
		double a = keyBoard.nextDouble();
		int[] a_array = new int[n];
		String a_string = "";
		
		for(int i = 0; i<n ;i++)
		{
			a_array[i] = (int) (a%10);
			
			if(a_array[i] % 2 == 0  && a_array[i] > 2)
			{
				if(a_array[i]==4)
					a_string = a_string + "22";
				if(a_array[i]==6)
					a_string = a_string + "3";
				if(a_array[i]==8)
					a_string = a_string + "222";
				
					a_array[i]--;
			}

			if(a_array[i] != 1 && a_array[i] != 0)
				if(a_array[i]==9)
					a_string = a_string + "7332";
				else
					a_string = a_string + a_array[i];
			
			a/=10;
		}
		
		char[] a_charArray = a_string.toCharArray();
		
		for(int i = 0; i<a_charArray.length ;i++)
		{
			a_charArray[i]*=-1;
		}
				
		java.util.Arrays.sort(a_charArray);
		
		for(int i = 0; i<a_charArray.length ;i++)
		{
			a_charArray[i]*=-1;
		}	
		
		System.out.println(a_charArray);

	}

}
