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 A {
	public static void main(String[] args)
	{
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt(); sc.nextLine();
		String as = sc.nextLine().trim();
		int num2 =0, num3=0, num5=0, num7=0;
		
		for (int i=0; i<n; i++)
		{
			int digit = Integer.parseInt(Character.toString(as.charAt(i)));
			if (digit == 2) num2++;
			if (digit == 3) num3++;
			if (digit == 4) {num2+=2; num3++;}
			if (digit == 5) {num5++;}
			if (digit == 6) {num3++; num5++;}
			if (digit == 7) {num7++;}
			if (digit == 8) {num2+=3; num7++;}
			if (digit == 9) {num2++; num3+=2; num7++;}
		}
		for (int i=0; i<num7; i++)
			System.out.print(7);
		for (int i=0; i<num5; i++)
			System.out.print(5);
		for (int i=0; i<num3; i++)
			System.out.print(3);
		for (int i=0; i<num2; i++)
			System.out.print(2);
		System.out.println();
	}
}
