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.*;
import java.util.*;

public class cf292C {
	static InputReader in = new InputReader();
	static String str = "";
	static String[] arr;
	
	public static void main(String[] args) throws Exception {
		int n = Integer.parseInt(in.readLine());
		str = in.readLine();
		int[] count = new int[10];
		for(char c : str.toCharArray()) {
			count[c - 48]++;
		}
		int[] newcount = new int[10];
		newcount[7] = count[9] + count[8] + count[7];
		newcount[5] = count[6] + count[5];
		newcount[3] = 2 * count[9] + count[6] + count[4] + count[3];
		newcount[2] = count[9] + 3 * count[8] + 2 * count[4] + count[2];
		for(int i = 0; i < newcount[7]; i++) {
			System.out.print('7');
		}
		for(int i = 0; i < newcount[5]; i++) {
			System.out.print('5');
		}
		for(int i = 0; i < newcount[3]; i++) {
			System.out.print('3');
		}
		for(int i = 0; i < newcount[2]; i++) {
			System.out.print('2');
		}
		System.out.println();
	}

	static class InputReader {
		BufferedReader br;
		public InputReader() {
			try {
				br = new BufferedReader(new FileReader("cf292C.in"));
			} catch(Exception e) {
				br = new BufferedReader(new InputStreamReader(System.in));
			}
		}

		public String readLine() throws Exception {
			return br.readLine();
		}
	}
}