#include <bits/stdc++.h>
using namespace std;
int n;
string s;
int a[10];
int main() {
  ios::sync_with_stdio(0);
  cin >> n >> s;
  for (int i = 0; i < n; i++) a[s[i] - '0']++;
  a[2] += a[9] + a[8] * 3 + 2 * a[4];
  a[3] += 2 * a[9] + a[6] + a[4];
  a[5] += a[6];
  a[6] = a[4] = 0;
  a[7] += a[8] + a[9];
  for (int k = 7; k >= 2; k--) {
    for (int i = 1; i <= a[k]; i++) {
      cout << k;
    }
  }
  cout << endl;
  return 0;
}

### 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 n;
string s;
int a[10];
int main() {
  ios::sync_with_stdio(0);
  cin >> n >> s;
  for (int i = 0; i < n; i++) a[s[i] - '0']++;
  a[2] += a[9] + a[8] * 3 + 2 * a[4];
  a[3] += 2 * a[9] + a[6] + a[4];
  a[5] += a[6];
  a[6] = a[4] = 0;
  a[7] += a[8] + a[9];
  for (int k = 7; k >= 2; k--) {
    for (int i = 1; i <= a[k]; i++) {
      cout << k;
    }
  }
  cout << endl;
  return 0;
}

```