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;
bool cmp(char a, char b) { return a > b; }
char res[102000];
int ires;
int main() {
  char s[100];
  int n;
  cin >> n >> s;
  int slen = strlen(s);
  for (int i = 0; i < slen; ++i) {
    int k = s[i] - '0';
    if (k == 2) {
      res[ires++] = 2 + '0';
    }
    if (k == 3) {
      res[ires++] = 3 + '0';
    }
    if (k == 4) {
      res[ires++] = 3 + '0';
      res[ires++] = 2 + '0';
      res[ires++] = 2 + '0';
    }
    if (k == 5) {
      res[ires++] = 5 + '0';
    }
    if (k == 6) {
      res[ires++] = 5 + '0';
      res[ires++] = 3 + '0';
    }
    if (k == 7) {
      res[ires++] = 7 + '0';
    }
    if (k == 8) {
      res[ires++] = 7 + '0';
      res[ires++] = 2 + '0';
      res[ires++] = 2 + '0';
      res[ires++] = 2 + '0';
    }
    if (k == 9) {
      res[ires++] = 7 + '0';
      res[ires++] = 2 + '0';
      res[ires++] = 3 + '0';
      res[ires++] = 3 + '0';
    }
  }
  sort(res, res + ires, cmp);
  cout << res;
  return 0;
}
