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;
char a[16];
int f[10];
int main() {
  int n, i;
  memset(f, 0, sizeof(f));
  cin >> n >> a;
  for (i = 0; i < n; i++) {
    if (a[i] == '4') {
      f[2] += 2;
      f[3]++;
    } else if (a[i] == '6') {
      f[5]++;
      f[3]++;
    } else if (a[i] == '8') {
      f[7]++;
      f[2] += 3;
    } else if (a[i] == '9') {
      f[7]++;
      f[3] += 2;
      f[2]++;
    } else
      f[a[i] - '0']++;
  }
  for (i = 7; i >= 2; i--) {
    while (f[i]--) cout << i;
  }
  cout << endl;
}
