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.PriorityQueue;
import java.util.Scanner;
import java.util.TreeSet;

public class CF292 {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int n = in.nextInt();
        char[] str = in.next().toCharArray();
        PriorityQueue<Character> pq = new PriorityQueue<Character>();
        for (int i = 0; i < str.length; i++) {
            if (str[i] == '9') {
                pq.add('2');
                pq.add('3');
                pq.add('3');
                pq.add('7');
            } else if (str[i] == '8') {
                pq.add('2');
                pq.add('2');
                pq.add('2');
                pq.add('7');
            } else if (str[i] == '7') {
                pq.add('7');
            } else if (str[i] == '6') {
                pq.add('5');
                pq.add('3');
            } else if (str[i] == '5') {
                pq.add('5');
            } else if (str[i] == '4') {
                pq.add('2');
                pq.add('2');
                pq.add('3');
            } else if (str[i] == '3') {
                pq.add('3');
            } else if (str[i] == '2') {
                pq.add('2');
            }
        }
        String s = "";
        while (!pq.isEmpty())
            s = pq.poll() + s;
        System.out.println(s);
    }
}
