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[10] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
void l(int w) { f[w]++; }
int main() {
  int q, w, e, r;
  char a[20];
  cin >> q >> a;
  for (w = 0; w < q; w++) {
    e = a[w] - 48;
    if (e == 2) l(2);
    if (e == 3) l(3);
    if (e == 4) {
      l(3);
      l(2);
      l(2);
    }
    if (e == 5) {
      l(5);
    }
    if (e == 6) {
      l(5);
      l(3);
    }
    if (e == 7) {
      l(7);
    }
    if (e == 8) {
      l(2);
      l(2);
      l(2);
      l(7);
    }
    if (e == 9) {
      l(2);
      l(3);
      l(3);
      l(7);
    }
  }
  for (w = 9; w > 0; w--)
    for (e = 0; e < f[w]; e++) cout << w;
  return 0;
}
