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 main {
	public static void main(String args[]){
		Scanner sc = new Scanner(System.in);
		int n=sc.nextInt();
		int m=n;
		sc.nextLine();
		String x=sc.nextLine();
		x=x+x+x+x+x+x;
		String arr[]=x.split("");
		for(int i=0;i<n;i++){
			if(arr[i].compareTo("4")==0){
				arr[i]="3";
				arr[m++]="2";
				arr[m++]="2";
			}
			else if(arr[i].compareTo("6")==0){
				arr[i]="5";
				arr[m++]="3";
			}
			else if(arr[i].compareTo("8")==0){
				arr[i]="7";
				arr[m++]="2";
				arr[m++]="2";
				arr[m++]="2";
			}
			else if(arr[i].compareTo("9")==0){
				arr[i]="7";
				arr[m++]="2";
				arr[m++]="3";
				arr[m++]="3";
			
			}
		}
		String ans="";
		for(int j=7;j>1;j--){
			String c=String.valueOf(j);
			for(int i=0;i<m;i++){
				if(arr[i].compareTo(c)==0){
					ans=ans+arr[i];
				}
			}
		}
		System.out.println(ans);
	}
}
