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 n, ar[100001];
string s;
vector<int> vec;
int main() {
  cin >> n;
  cin >> s;
  for (int i = 0; i < n; i++) {
    int f = s[i] - 48;
    int y;
    for (int p = 2; p <= f; p++) {
      y = p;
      while (y > 1) {
        int u = 2;
        for (u; u <= y; u++) {
          if (y % u == 0) {
            break;
          }
        }
        ar[u]++;
        y = y / u;
      }
    }
  }
  while (ar[7]) {
    cout << "7";
    ar[7]--;
    ar[5]--;
    ar[2] = ar[2] - 4;
    ar[3] = ar[3] - 2;
  }
  while (ar[5]) {
    cout << "5";
    ar[5]--;
    ar[2] = ar[2] - 3;
    ar[3] = ar[3] - 1;
  }
  while (ar[3]) {
    cout << "3";
    ar[2] = ar[2] - 1;
    ar[3] = ar[3] - 1;
  }
  while (ar[2]) {
    cout << "2";
    ar[2] = ar[2] - 1;
  }
  return 0;
}
