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>
#include <bits/stdc++.h>
using namespace std;
const int MAX_N = 25;
char st[MAX_N];
int digit_num[10];
int n;
int main() {
  scanf("%d", &n);
  scanf("%s", st);
  for (int i = 0; i < n; i++) {
    int temp = st[i] - '0';
    digit_num[temp]++;
  }
  digit_num[2] += digit_num[9];
  digit_num[3] += digit_num[9] * 2;
  digit_num[7] += digit_num[9];
  digit_num[9] = 0;
  digit_num[2] += digit_num[8] * 3;
  digit_num[7] += digit_num[8];
  digit_num[8] = 0;
  digit_num[3] += digit_num[6];
  digit_num[5] += digit_num[6];
  digit_num[6] = 0;
  digit_num[2] += digit_num[4] * 2;
  digit_num[3] += digit_num[4];
  digit_num[4] = 0;
  for (int i = 9; i > 1; i--) {
    for (int j = 0; j < digit_num[i]; j++) {
      putchar(i + '0');
    }
  }
  puts("");
  return 0;
}
