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() {
  int n;
  cin >> n;
  string s;
  cin >> s;
  vector<char> result;
  int i = 0;
  while (i < n) {
    if (s[i] == '1' || s[i] == '0') {
      i++;
      continue;
    }
    if (s[i] == '4') {
      result.push_back('3');
      result.push_back('2');
      result.push_back('2');
      i++;
      continue;
    }
    if (s[i] == '6') {
      result.push_back('5');
      result.push_back('3');
      i++;
      continue;
    }
    if (s[i] == '8') {
      result.push_back('7');
      result.push_back('2');
      result.push_back('2');
      result.push_back('2');
      i++;
      continue;
    }
    if (s[i] == '9') {
      result.push_back('7');
      result.push_back('3');
      result.push_back('3');
      result.push_back('2');
      i++;
      continue;
    }
    result.push_back(s[i]);
    i++;
  }
  sort(result.begin(), result.end(), greater<int>());
  for (auto elem : result) cout << elem;
  return 0;
}
