#include <bits/stdc++.h>
using namespace std;
int main() {
  long long n;
  map<int, int> m;
  cin >> n;
  string s;
  cin >> s;
  for (int i = 0; i < n; ++i) {
    m[s[i] - '0']++;
  }
  m[3] += (m[6] + m[4] + (2 * m[9]));
  m[2] += ((2 * m[4]) + (3 * m[8]) + m[9]);
  m[5] += m[6];
  m[7] += (m[8] + m[9]);
  while (m[7]--) {
    cout << '7';
  }
  while (m[5]--) {
    cout << '5';
  }
  while (m[3]--) {
    cout << '3';
  }
  while (m[2]--) {
    cout << '2';
  }
  return 0;
}

### Prompt

In Cpp, your task is to solve 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() {
  long long n;
  map<int, int> m;
  cin >> n;
  string s;
  cin >> s;
  for (int i = 0; i < n; ++i) {
    m[s[i] - '0']++;
  }
  m[3] += (m[6] + m[4] + (2 * m[9]));
  m[2] += ((2 * m[4]) + (3 * m[8]) + m[9]);
  m[5] += m[6];
  m[7] += (m[8] + m[9]);
  while (m[7]--) {
    cout << '7';
  }
  while (m[5]--) {
    cout << '5';
  }
  while (m[3]--) {
    cout << '3';
  }
  while (m[2]--) {
    cout << '2';
  }
  return 0;
}

```