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.io.*;

public class Div1_292_A {
	static int []factors = new int[8];
	static int []pFactors = {2,3,5,7};
	static int digitsCnt;
	
	public static void main(String[] args) throws IOException {
		BufferedInputStream bis = new BufferedInputStream(System.in);
		BufferedReader br = new BufferedReader(new InputStreamReader(bis));
		int n = Integer.parseInt(br.readLine().trim());
		String in = br.readLine().trim();
		for(int i = 0;i<in.length();i++)
			update(in.charAt(i)-'0');
		StringBuilder res = new StringBuilder("");
		for(int j = 7;j > 1;j--)
			for(int k = 0;k < factors[j];k++)
				res.append(j);
		System.out.println(res);
	}
	public static void update(int j) {
		if(j==2||j==3||j==5||j==7)
			factors[j]++;
		else if(j==9) {
			factors[7]++;
			factors[3]+=2;
			factors[2]++;
		}else if(j==8) {
			factors[2]+=3;
			factors[7]++;
		}else if(j==6) {
			factors[3]++;
			factors[5]++;
		}else if(j==4){
			factors[2]+=2;
			factors[3]++;
		}
	}
}