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>
#include <bits/stdc++.h>
#pragma comment(linker, "/STACK:640000000")
using namespace std;
int main() {
  string s;
  int n;
  cin >> n;
  cin >> s;
  string ans;
  for (int _n((n)-1), i(0); i <= _n; ++i) {
    if (s[i] == '0' || s[i] == '1') continue;
    switch (s[i]) {
      case '4':
        ans += "223";
        break;
      case '6':
        ans += "53";
        break;
      case '8':
        ans += "7222";
        break;
      case '9':
        ans += "7332";
        break;
      default:
        ans += s[i];
        break;
    }
  }
  sort((ans).begin(), (ans).end());
  reverse((ans).begin(), (ans).end());
  cout << ans << endl;
  return 0;
}
