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;
string ans;
void plu(int x) {
  if (x == 2) ans += "2";
  if (x == 3) ans += "3";
  if (x == 4) ans += "322";
  if (x == 5) ans += "5";
  if (x == 6) ans += "35";
  if (x == 7) ans += "7";
  if (x == 8) ans += "2227";
  if (x == 9) ans += "3327";
}
bool cmp(char x, char y) { return x > y; }
int main() {
  int n, i;
  char x;
  scanf("%d", &n);
  getchar();
  for (i = 1; i <= n; i++) {
    scanf("%c", &x);
    plu(x - '0');
  }
  sort(ans.begin(), ans.end(), cmp);
  cout << ans;
}
