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 a[10], i, j, k, n, t;
  char c;
  cin >> n;
  for (i = 0; i < 10; i++) a[i] = 0;
  for (i = 0; i < n; i++) {
    cin >> c;
    if (c <= '9' && c >= '0') {
      k = c - '0';
      for (j = 2; j <= k; j++) {
        if (j == 9)
          a[3] += 2;
        else if (j == 8)
          a[2] += 3;
        else if (j == 6) {
          a[2]++;
          a[3]++;
        } else if (j == 4)
          a[2] += 2;
        else
          a[j]++;
      }
    }
  }
  while (a[7] > 0) {
    cout << "7";
    a[7]--;
    a[3] = a[3] - 2;
    a[2] = a[2] - 4;
    a[5]--;
  }
  while (a[5] > 0) {
    cout << "5";
    a[3]--;
    a[2] = a[2] - 3;
    a[5]--;
  }
  while (a[3] > 0) {
    cout << "3";
    a[2]--;
    a[3]--;
  }
  while (a[2] > 0) {
    cout << "2";
    a[2]--;
  }
  cout << endl;
}
