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 cc3 {

    static class FastReader {
        BufferedReader br;
        StringTokenizer st;

        public FastReader() {
            br = new BufferedReader(new
                    InputStreamReader(System.in));
        }

        String next() {
            while (st == null || !st.hasMoreElements()) {
                try {
                    st = new StringTokenizer(br.readLine());
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        }

        int nextInt() {
            return Integer.parseInt(next());
        }

        long nextLong() {
            return Long.parseLong(next());
        }

        double nextDouble() {
            return Double.parseDouble(next());
        }

        String nextLine() {
            String str = "";
            try {
                str = br.readLine();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return str;
        }
    }

    public static void main(String[] args) {
        FastReader fr = new FastReader();
        int n = fr.nextInt();
        String s = fr.next();
        int cnt[] = new int[10];
        for(int i=0;i<s.length();++i){
            int num = (s.charAt(i)-'0');
            for(int j=num;j>1;--j){
                ++cnt[j];
            }
        }
        cnt[2] += cnt[4]*2;
        cnt[2] += cnt[8]*3;
        cnt[2] += cnt[6]*1;
        cnt[3] += cnt[9]*2;
        cnt[3] += cnt[6]*1;
        /*for(int i=1;i<=9;++i){
            System.out.println(i+" -> "+cnt[i]);
        }*/
        for(int i=0;i<cnt[7];++i){
            System.out.print("7");
            cnt[2] -= 1; // For 2
            cnt[2] -= 2; // For 4
            cnt[2] -= 1; // For 6
            cnt[3] -= 1; // For 3
            cnt[3] -= 1; // For 6
            cnt[5] -= 1; // For 5
        }
        for(int i=0;i<cnt[5];++i){
            System.out.print("5");
            cnt[2] -= 1; // For 2
            cnt[2] -= 2; // For 4
            cnt[3] -= 1; // For 3
        }
        for(int i=0;i<cnt[3];++i){
            System.out.print("3");
            cnt[2] -= 1; // For 2
        }
        for(int i=0;i<cnt[2];++i){
            System.out.print("2");
        }
    }
}
