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 n, a[10];
  char s[1004];
  scanf("%d", &n);
  scanf("%s", s);
  for (int i = 0; i < 10; i++) a[i] = 0;
  for (int i = 0; i < n; i++) {
    if (s[i] == '0' || s[i] == '1') continue;
    if (s[i] == '2') a[2]++;
    if (s[i] == '3') a[3]++;
    if (s[i] == '4') a[2] += 2, a[3] += 1;
    if (s[i] == '5') a[5]++;
    if (s[i] == '6') a[3]++, a[5]++;
    if (s[i] == '7') a[7]++;
    if (s[i] == '8') a[2] += 3, a[7]++;
    if (s[i] == '9') a[3] += 2, a[2] += 1, a[7]++;
  }
  for (int i = int(7); i >= int(2); i--) {
    for (int j = 0; j < a[i]; j++) printf("%d", i);
  }
  return 0;
}
