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;
  scanf("%d", &n);
  vector<int> vec;
  for (int i = 0; i < n; i++) {
    int d;
    scanf("%1d", &d);
    if (d == 2 || d == 3 || d == 5 || d == 7)
      vec.push_back(d);
    else if (d == 4)
      vec.push_back(3), vec.push_back(2), vec.push_back(2);
    else if (d == 6)
      vec.push_back(5), vec.push_back(3);
    else if (d == 8)
      vec.push_back(7), vec.push_back(2), vec.push_back(2), vec.push_back(2);
    else if (d == 9)
      vec.push_back(7), vec.push_back(3), vec.push_back(3), vec.push_back(2);
  }
  sort(vec.begin(), vec.end());
  for (int i = vec.size(); i--;) printf("%d", vec[i]);
  puts("");
}
