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 in = new Scanner(System.in);
		int n = Integer.parseInt(in.nextLine());
		String s = in.nextLine();
		int[] arr = new int[10];
		for (int i = 0; i < n; ++i) countFact(s.charAt(i), arr, false);
		for (int i = 9; i >= 0; --i) while (arr[i] > 0) {
			System.out.printf("%d", i);
			countFact((char) ('0' + i), arr, true);
		}
		in.close();
	}
	public static void countFact(char c, int[] arr, boolean flag) {
		switch (c) {
		case '9': arr[3] += (flag ? -2 : 2);
		case '8': arr[2] += (flag ? -3 : 3);
		case '7': arr[7] += (flag ? -1 : 1);
		case '6': arr[3] += (flag ? -1 : 1); arr[2] += (flag ? -1 : 1);
		case '5': arr[5] += (flag ? -1 : 1);
		case '4': arr[2] += (flag ? -2 : 2);
		case '3': arr[3] += (flag ? -1 : 1);
		case '2': arr[2] += (flag ? -1 : 1);
		default: break;
		}
	}
}
