#include <bits/stdc++.h>
using namespace std;
int main() {
  int64_t n, a2 = 0, a3 = 0, a5 = 0, a7 = 0;
  char c;
  cin >> n;
  while (n--) {
    cin >> c;
    if (c == '0' || c == '1') continue;
    if (c == '2')
      a2++;
    else if (c == '3')
      a3++;
    else if (c == '4') {
      a3++;
      a2 = a2 + 2;
    } else if (c == '5')
      a5++;
    else if (c == '6') {
      a5++;
      a3++;
    } else if (c == '7') {
      a7++;
    } else if (c == '8') {
      a7++;
      a2 = a2 + 3;
    } else {
      a7++;
      a2++;
      a3 = a3 + 2;
    }
  }
  while (a7--) cout << '7';
  while (a5--) cout << '5';
  while (a3--) cout << '3';
  while (a2--) cout << '2';
}

### Prompt

Your task is to create a cpp solution to the following problem:

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() {
  int64_t n, a2 = 0, a3 = 0, a5 = 0, a7 = 0;
  char c;
  cin >> n;
  while (n--) {
    cin >> c;
    if (c == '0' || c == '1') continue;
    if (c == '2')
      a2++;
    else if (c == '3')
      a3++;
    else if (c == '4') {
      a3++;
      a2 = a2 + 2;
    } else if (c == '5')
      a5++;
    else if (c == '6') {
      a5++;
      a3++;
    } else if (c == '7') {
      a7++;
    } else if (c == '8') {
      a7++;
      a2 = a2 + 3;
    } else {
      a7++;
      a2++;
      a3 = a3 + 2;
    }
  }
  while (a7--) cout << '7';
  while (a5--) cout << '5';
  while (a3--) cout << '3';
  while (a2--) cout << '2';
}

```