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 TaskOne{
  public static void main(String[] args) {
    int c2=0,c3=0,c5=0,c7=0;

    Scanner in = new Scanner(System.in);

    int s = in.nextInt();
    String n = String.valueOf(in.next());
    for (int i = 0; i<s; i++) {
      int w = Integer.parseInt(String.valueOf(n.charAt(i)));
      while(w>1){
        if(w==2) c2++;
        else if(w==3) c3++;
        else if(w==4) c2+=2;
        else if(w==5) c5++;
        else if(w==6) {c3+=1; c2+=1;}
        else if(w==7) c7++;
        else if(w==8) c2+=3;
        else if(w==9) c3+=2;
        w--;
      }
    }
    if(c7>0){
      for (int i = 0; i<c7; i++) {
        System.out.print(7);
        c5--; c3-=2; c2-=4;
      }
    }
    if(c5>0){
      for (int i = 0; i<c5; i++) {
        System.out.print(5);
        c3-=1; c2-=3;
      }
    }
    if(c3>0){
      for (int i = 0; i<c3; i++) {
        System.out.print(3);
      }
      c2=c2-c3;
    }
    if(c2>0){
      for (int i = 0; i<c2; i++) {
        System.out.print(2);
      }
    }
  }
}
