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;
int main() {
  int n;
  scanf("%d", &n);
  int res[10];
  memset(res, 0, sizeof(res));
  char s[20];
  memset(s, 0, sizeof(s));
  scanf("%s", s);
  for (int i = 0; s[i]; i++) {
    if (s[i] != '0' && s[i] != '1') {
      switch (s[i]) {
        case '2':
          res[2]++;
          break;
        case '3':
          res[3]++;
          break;
        case '4':
          res[3]++;
          res[2] += 2;
          break;
        case '5':
          res[5]++;
          break;
        case '6':
          res[3]++;
          res[5]++;
          break;
        case '7':
          res[7]++;
          break;
        case '8':
          res[7]++;
          res[2] += 3;
          break;
        case '9':
          res[7]++;
          res[3] += 2;
          res[2]++;
          break;
      }
    }
  }
  for (int i = 9; i >= 0; i--) {
    for (int j = 1; j <= res[i]; j++) {
      printf("%d", i);
    }
  }
  printf("\n");
  return 0;
}
