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 Factorial {

	private static char[] chNums;
	
	public static void main(String[] args) {
		
		Scanner in = new Scanner(System.in);
		
		int n = in.nextInt();
		String nums = in.next();
		
		nums = nums.replaceAll("0", "");
		nums = nums.replaceAll("1", "");
		nums = nums.replaceAll("4", "322");
		nums = nums.replaceAll("6", "53");
		nums = nums.replaceAll("8", "7222");
		nums = nums.replaceAll("9", "7332");
		
		chNums = nums.toCharArray();

		Arrays.sort(chNums);
		
		char temp;
		for (int i = 0, j = chNums.length - 1; i <= j; i++, j--) {
			temp = chNums[i];
			chNums[i] = chNums[j];
			chNums[j] = temp;
		}
		
		String ans = "";
		
		for (int i = 0; i < chNums.length; i++)
			ans += chNums[i];
		
		System.out.println(ans);

	}
	
}