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.Arrays;
import java.util.Scanner;

public class _1drazil {

	public static void main(String[] args) {
Scanner scn=new Scanner(System.in);
int n=scn.nextInt();
String s=scn.next();
String k=s.replaceAll("9", "7332");
String t=k.replaceAll("8", "7222");
String l=t.replaceAll("6", "53");
String m=l.replaceAll("4", "322");
char []ch=m.toCharArray();
Arrays.sort(ch);
int i=0;
while(ch[i]=='1'||ch[i]=='0'){
	i++;
}
for(int v=m.length()-1;v>=i;v--){
	System.out.print(ch[v]);
}



	}

}
