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.*;
public class KnightTemplar {
public static void main(String [] args){
	Scanner in=new Scanner(System.in);
	int n=in.nextInt();
	String str=in.next();
	String array[]={"0","1","2","3","223","5","35","7","2227","3327"};
	int ptr=0;
	String temp="";
	for(int i=0;i<str.length();i++){
	if(str.charAt(i)=='1'||str.charAt(i)=='0')continue;	
	temp=temp+(array[str.charAt(i)-48]);
	}
	char store[]=temp.toCharArray();
	Arrays.sort(store);
	StringBuilder sb=new StringBuilder();
	for(int i=store.length-1;i>=0;i--){
		sb.append(store[i]);
	}
	System.out.print(sb);
	}
}
   