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.Scanner;

public class C {

  public static void main(String[] args) {
    Scanner in = new Scanner(System.in);
    in.nextInt();
    int[] counts = new int[10];
    String string = in.next();
    for (char c : string.toCharArray()) {
      int d = c - '0';
      if (d == 4) {
        counts[2] += 2;
        counts[3]++;
      } else if (d == 6) {
        counts[3]++;
        counts[5]++;
      } else if (d == 8) {
        counts[2] += 3;
        counts[7]++;
      } else if (d == 9) {
        counts[3] += 2;
        counts[2] ++;
        counts[7]++;
      } else {
        counts[d]++;
      }
    }
    for (int i = 9; i > 1; i--) {
      for (int count = 0; count < counts[i]; count++) {
        System.out.print(i);
      }
    }
  }
}
