#include <bits/stdc++.h>
using namespace std;
int main() {
  string s, arr[10] = {"", "", "2", "3", "223", "5", "53", "7", "7222", "7332"};
  long long nume, t;
  cin >> t >> nume;
  while (nume > 0) {
    s += arr[nume % 10];
    nume /= 10;
  }
  sort(s.rbegin(), s.rend());
  cout << s << endl;
  return 0;
}

### Prompt

Construct a cpp code solution to the problem outlined:

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>

### Response

```cpp
#include <bits/stdc++.h>
using namespace std;
int main() {
  string s, arr[10] = {"", "", "2", "3", "223", "5", "53", "7", "7222", "7332"};
  long long nume, t;
  cin >> t >> nume;
  while (nume > 0) {
    s += arr[nume % 10];
    nume /= 10;
  }
  sort(s.rbegin(), s.rend());
  cout << s << endl;
  return 0;
}

```