#include <bits/stdc++.h>
using namespace std;
const int N = 2005;
const int M = 200 + 5;
int main() {
  vector<int> v[10];
  v[2].push_back(2);
  v[3].push_back(3);
  v[4].push_back(2);
  v[4].push_back(2);
  v[4].push_back(3);
  v[5].push_back(5);
  v[6].push_back(3);
  v[6].push_back(5);
  v[7].push_back(7);
  v[8].push_back(2);
  v[8].push_back(2);
  v[8].push_back(2);
  v[8].push_back(7);
  v[9].push_back(2);
  v[9].push_back(3);
  v[9].push_back(3);
  v[9].push_back(7);
  string s;
  int n;
  priority_queue<int> q;
  cin >> n >> s;
  for (int i = 0; i < s.length(); i++) {
    for (int j = 0; j < v[s[i] - '0'].size(); j++) q.push(v[s[i] - '0'][j]);
  }
  while (q.size()) {
    cout << q.top();
    q.pop();
  }
  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;
const int N = 2005;
const int M = 200 + 5;
int main() {
  vector<int> v[10];
  v[2].push_back(2);
  v[3].push_back(3);
  v[4].push_back(2);
  v[4].push_back(2);
  v[4].push_back(3);
  v[5].push_back(5);
  v[6].push_back(3);
  v[6].push_back(5);
  v[7].push_back(7);
  v[8].push_back(2);
  v[8].push_back(2);
  v[8].push_back(2);
  v[8].push_back(7);
  v[9].push_back(2);
  v[9].push_back(3);
  v[9].push_back(3);
  v[9].push_back(7);
  string s;
  int n;
  priority_queue<int> q;
  cin >> n >> s;
  for (int i = 0; i < s.length(); i++) {
    for (int j = 0; j < v[s[i] - '0'].size(); j++) q.push(v[s[i] - '0'][j]);
  }
  while (q.size()) {
    cout << q.top();
    q.pop();
  }
  return 0;
}

```