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 f[8];
int main() {
  int n, d, i;
  string a;
  cin >> n;
  cin >> a;
  for (i = 0; i < a.size(); i++) {
    int j = a[i] - '0';
    for (d = j; d > 1; d--) {
      if (d == 7 || d == 5 || d == 3 || d == 2) f[d]++;
      if (d == 9) f[3] += 2;
      if (d == 8) f[2] += 3;
      if (d == 6) {
        f[2]++;
        f[3]++;
      }
      if (d == 4) f[2] += 2;
    }
  }
  for (i = 0; i < f[7]; i++) cout << 7;
  f[5] -= f[7];
  f[3] -= 2 * f[7];
  f[2] -= 4 * f[7];
  for (i = 0; i < f[5]; i++) cout << 5;
  f[3] -= f[5];
  f[2] -= 3 * f[5];
  for (i = 0; i < f[3]; i++) cout << 3;
  for (i = 0; i < f[2] - f[3]; i++) cout << 2;
  cout << endl;
  return 0;
}
