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;
const int oo = 1 << 30;
const double PI = M_PI;
const double EPS = 1e-15;
int n;
string second, answer;
int main() {
  cin.sync_with_stdio(false);
  cin >> n;
  cin >> second;
  for (int i = 0; i < n; i++) {
    if (second[i] == '2') answer += "2";
    if (second[i] == '3') answer += "3";
    if (second[i] == '4') answer += "322";
    if (second[i] == '5') answer += "5";
    if (second[i] == '6') answer += "53";
    if (second[i] == '7') answer += "7";
    if (second[i] == '8') answer += "7222";
    if (second[i] == '9') answer += "7332";
  }
  sort(answer.begin(), answer.end());
  reverse(answer.begin(), answer.end());
  cout << answer << endl;
  return 0;
}
