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 i, j, k, m, n;
  string s;
  int number[12];
  while (cin >> n) {
    memset(number, 0, sizeof(number));
    cin >> s;
    for (i = 0; i < s.size(); i++) {
      j = s[i] - '0';
      if (j == 2 || j == 3 || j == 5 || j == 7)
        number[j]++;
      else if (j == 4) {
        number[2] = number[2] + 2;
        number[3]++;
      } else if (j == 6) {
        number[3]++;
        number[5]++;
      } else if (j == 8) {
        number[2] = number[2] + 3;
        number[7]++;
      } else if (j == 9) {
        number[3] = number[3] + 2;
        number[2]++;
        number[7]++;
      }
    }
    for (i = 9; i > 1; i--) {
      while (number[i]) {
        cout << i;
        number[i]--;
      }
    }
    cout << endl;
  }
  return 0;
}
