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 s;
int n, cnt[10];
int main() {
  cin >> n;
  cin >> s;
  for (int i = 0; i < s.size(); ++i) {
    int temp = s[i] - '0';
    for (int j = 2; j <= temp; ++j) {
      if (j == 4) {
        cnt[2] += 2;
      } else if (j == 6) {
        cnt[2] += 1;
        cnt[3] += 1;
      } else if (j == 8) {
        cnt[2] += 3;
      } else if (j == 9) {
        cnt[3] += 2;
      } else
        cnt[j] += 1;
    }
  }
  for (int i = 9; i > 1; --i) {
    while (cnt[i]--) {
      cout << i;
      for (int j = 2; j < i; ++j) {
        if (j == 4) {
          cnt[2] -= 2;
        } else if (j == 6) {
          cnt[2] -= 1;
          cnt[3] -= 1;
        } else if (j == 8) {
          cnt[2] -= 3;
        } else if (j == 9) {
          cnt[3] -= 2;
        } else
          cnt[j] -= 1;
      }
    }
  }
  return 0;
}
