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;
  while (cin >> n) {
    string s;
    cin >> s;
    string res = "";
    for (int i = 0; i < n; i++) {
      if (s[i] <= '1')
        continue;
      else {
        if (s[i] == '4')
          res += '3', res += '2', res += '2';
        else {
          if (s[i] == '6')
            res += '5', res += '3';
          else {
            if (s[i] == '8')
              res += '7', res += '2', res += '2', res += '2';
            else {
              if (s[i] == '9')
                res += '3', res += '3', res += '2', res += '7';
              else
                res += s[i];
            }
          }
        }
      }
    }
    sort(res.begin(), res.end());
    reverse(res.begin(), res.end());
    cout << res << endl;
  }
}
