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.PrintWriter;
import java.util.Collection;
import java.util.Collections;
import java.util.PriorityQueue;
import java.util.Scanner;

public class cf515c {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		char[] arr = sc.next().toCharArray();
		sc.close();
		PriorityQueue<Integer> res = new PriorityQueue<>(Collections.reverseOrder());
		int[][] map = { {},{}, {2},{3},{3,2,2},{5},{5,3},{7},{7,2,2,2},{7,3,3,2} };
		for (int i=0;i<arr.length;i++) {
			if (arr[i]!='0' && arr[i]!='1') {
				int dig = Character.getNumericValue(arr[i]);
				int[] mp = map[dig];
				for (int j=0;j<mp.length;j++) {
					res.add(mp[j]);
				}
			}
		}
		PrintWriter out = new PrintWriter(System.out);
		while(!res.isEmpty()) {
			out.print(res.poll());
		}
		out.flush();out.close();
	}
}
