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 n;
string num, s = "";
vector<int> myvec;
int main() {
  ios_base::sync_with_stdio(false);
  cin >> n;
  cin >> num;
  for (int i = 0; i < n; i++)
    if (num[i] != '0' && num[i] != '1') myvec.push_back(int(num[i]) - 48);
  for (int i = 0; i < myvec.size(); i++) {
    if (myvec[i] == 2)
      s += "2";
    else if (myvec[i] == 3)
      s += "3";
    else if (myvec[i] == 4)
      s += "322";
    else if (myvec[i] == 5)
      s += "5";
    else if (myvec[i] == 6)
      s += "53";
    else if (myvec[i] == 7)
      s += "7";
    else if (myvec[i] == 8)
      s += "7222";
    else if (myvec[i] == 9)
      s += "7332";
  }
  sort(s.begin(), s.end());
  reverse(s.begin(), s.end());
  cout << s << endl;
}
