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;
int main() {
  ios_base::sync_with_stdio(NULL);
  cin.tie(0);
  cout.tie(0);
  cout << fixed;
  cout.precision(10);
  int t = 1;
  while (t--) {
    int n;
    cin >> n;
    string second;
    cin >> second;
    int a[n];
    for (int i = 0; i < n; i++) {
      a[i] = second[i] - '0';
    }
    string s1[] = {"", "1", "2", "3", "322", "5", "53", "7", "7222", "7332"};
    string ans = "";
    for (int i = 0; i < n; i++) {
      if (a[i] > 1) {
        ans += s1[a[i]];
      }
    }
    sort(ans.begin(), ans.end());
    reverse(ans.begin(), ans.end());
    cout << ans << ("\n");
    ;
  }
  return 0;
}
