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;
vector<int> v;
void desc(long long n) {
  if (!n) return;
  if (n % 10 == 4) {
    v.push_back(2);
    v.push_back(2);
    desc(3);
  } else if (n % 10 == 8) {
    v.push_back(2);
    v.push_back(2);
    v.push_back(2);
    desc(7);
  } else if (n % 10 == 6) {
    v.push_back(3);
    desc(5);
  } else if (n % 10 == 9) {
    v.push_back(2);
    v.push_back(3);
    v.push_back(3);
    desc(7);
  } else if (n % 10 > 1)
    v.push_back(n % 10);
  desc(n / 10);
}
int main() {
  int x;
  long long n;
  cin >> x >> n;
  desc(n);
  sort(v.rbegin(), v.rend());
  for (int i = 0; i < v.size(); ++i) cout << v[i];
}
