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 cnt[10] = {0}, n;
  char ch;
  cin >> n;
  while (n--) {
    cin >> ch;
    switch (ch) {
      case '2':
        cnt[2]++;
        break;
      case '3':
        cnt[3]++;
        break;
      case '4':
        cnt[3]++;
        cnt[2] += 2;
        break;
      case '5':
        cnt[5]++;
        break;
      case '6':
        cnt[5]++;
        cnt[3]++;
        break;
      case '7':
        cnt[7]++;
        break;
      case '8':
        cnt[7]++;
        cnt[2] += 3;
        break;
      case '9':
        cnt[7]++;
        cnt[3] += 2;
        cnt[2]++;
        break;
    }
  }
  for (int i = 7; i > 1; i--) {
    while (cnt[i]--) {
      cout << i;
    }
  }
  cout << endl;
  return 0;
}
