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::sync_with_stdio(false);
  cin.tie(nullptr);
  int n;
  string S;
  cin >> n >> S;
  vector<int> digits;
  for (const auto c : S) {
    if (c == '2') {
      digits.emplace_back(2);
    } else if (c == '3') {
      digits.emplace_back(3);
    } else if (c == '4') {
      digits.emplace_back(3);
      digits.emplace_back(2);
      digits.emplace_back(2);
    } else if (c == '5') {
      digits.emplace_back(5);
    } else if (c == '6') {
      digits.emplace_back(5);
      digits.emplace_back(3);
    } else if (c == '7') {
      digits.emplace_back(7);
    } else if (c == '8') {
      digits.emplace_back(7);
      digits.emplace_back(2);
      digits.emplace_back(2);
      digits.emplace_back(2);
    } else if (c == '9') {
      digits.emplace_back(7);
      digits.emplace_back(2);
      digits.emplace_back(3);
      digits.emplace_back(3);
    }
  }
  sort(digits.begin(), digits.end(), greater<int>());
  for (const auto digit : digits) {
    cout << digit;
  }
  return 0;
}
