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.*;
import java.util.stream.IntStream;

public class C515 {

    public static final int[] EXPANSION_9 = {7, 3, 3, 2};
    public static final int[] EXPANSION_8 = {7, 2, 2, 2};
    public static final int[] EXPANSION_6 = {5, 3};
    public static final int[] EXPANSION_4 = {3, 2, 2};

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        sc.nextInt();
        sc.next().chars().map(ch -> ch - '0').flatMap(C515::getNumberExpansion).
                boxed().sorted(Comparator.reverseOrder()).forEach(System.out::print);
        sc.close();
    }

    private static IntStream getNumberExpansion(Integer ch) {
        switch (ch) {
            case 9:
                return Arrays.stream(EXPANSION_9);
            case 8:
                return Arrays.stream(EXPANSION_8);
            case 6:
                return Arrays.stream(EXPANSION_6);
            case 4:
                return Arrays.stream(EXPANSION_4);
            default:

                if (ch == 0 || ch == 1) {
                    int[] arr = {};
                    return Arrays.stream(arr);
                } else {
                    int[] arr = {ch};
                    return Arrays.stream(arr);
                }
        }
    }
}