#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base::sync_with_stdio(false);
  int n;
  string s;
  int a[10] = {};
  cin >> n;
  cin >> s;
  for (int i = 0; i < n; i++) a[s[i] - '0']++;
  a[2] += a[9], a[3] += a[9] * 2, a[7] += a[9], a[9] = 0;
  a[2] += a[8] * 3, a[7] += a[8], a[8] = 0;
  a[3] += a[6], a[5] += a[6], a[6] = 0;
  a[2] += a[4] * 2;
  a[3] += a[4];
  a[4] = 0;
  for (int i = 9; i >= 2; i--) {
    while (a[i]--) cout << i;
  }
  return 0;
}

### Prompt

Create a solution in Cpp for 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() {
  ios_base::sync_with_stdio(false);
  int n;
  string s;
  int a[10] = {};
  cin >> n;
  cin >> s;
  for (int i = 0; i < n; i++) a[s[i] - '0']++;
  a[2] += a[9], a[3] += a[9] * 2, a[7] += a[9], a[9] = 0;
  a[2] += a[8] * 3, a[7] += a[8], a[8] = 0;
  a[3] += a[6], a[5] += a[6], a[6] = 0;
  a[2] += a[4] * 2;
  a[3] += a[4];
  a[4] = 0;
  for (int i = 9; i >= 2; i--) {
    while (a[i]--) cout << i;
  }
  return 0;
}

```