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>
using namespace std;
const int INF = 1e9 + 5;
const int N = 2e5 + 123;
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  int n;
  cin >> n;
  string s;
  cin >> s;
  string ans = "";
  for (int i = 0; i < n; ++i) {
    if (s[i] == '2') {
      ans += '2';
    } else if (s[i] == '3') {
      ans += "3";
    } else if (s[i] == '4') {
      ans += "223";
    } else if (s[i] == '5') {
      ans += "5";
    } else if (s[i] == '6') {
      ans += "35";
    } else if (s[i] == '7') {
      ans += "7";
    } else if (s[i] == '8') {
      ans += "2227";
    } else if (s[i] == '9') {
      ans += "2337";
    }
  }
  sort((ans).rbegin(), (ans).rend());
  cout << ans;
}
