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 mod = 1000 * 1000 * 1000 + 7;
const int INF = 1000 * 1000 * 1000;
const long long LINF = (long long)INF * INF;
string a, ans;
int n;
int32_t main(void) {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  ;
  cin >> n >> a;
  sort((a).begin(), (a).end(), greater<char>());
  while (a.back() <= '1') a.pop_back();
  for (int i = (0); i < ((int)a.size()); i++) {
    int x = a[i] - '0';
    if (x == 2 || x == 3 || x == 5 || x == 7)
      ans += (x + '0');
    else if (x == 4)
      ans += "223";
    else if (x == 6)
      ans += "53";
    else if (x == 8)
      ans += "2227";
    else if (x == 9)
      ans += "3327";
  }
  sort((ans).begin(), (ans).end(), greater<char>());
  cout << ans << '\n';
  return 0;
}
