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.Arrays;
import java.util.List;
import java.util.Scanner;

public class C515 {
    private static final int MAX_N = 100001;
    private static final int A[][] = {{},{},{2},{3},{2,2,3},{5},{3,5},{7},{2,2,2,7},{2,3,3,7}};

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int n = scanner.nextInt();
        int[] ans = new int[100];
        int index = 0;
        String a = scanner.next();
        for(int i = 0;i<n;i++){
            int tmp = a.charAt(i)-'0';
            if(A[tmp].length > 0){
                for(int j = 0;j<A[tmp].length;j++){
                    ans[index++] = A[tmp][j];
                }
            }
        }
        Arrays.sort(ans,0,index);
        for(int i = index-1;i>=0;i--){
            System.out.print(ans[i]);
        }
        System.out.println();
    }
}
