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;
long long n, a;
vector<long long> v;
int32_t main() {
  scanf("%lld %lld", &n, &a);
  while (a) {
    if (a % 10 == 9) {
      v.push_back(7);
      v.push_back(3);
      v.push_back(3);
      v.push_back(2);
    }
    if (a % 10 == 8) {
      v.push_back(7);
      v.push_back(2);
      v.push_back(2);
      v.push_back(2);
    }
    if (a % 10 == 7) v.push_back(7);
    if (a % 10 == 6) {
      v.push_back(5);
      v.push_back(3);
    }
    if (a % 10 == 5) v.push_back(5);
    if (a % 10 == 4) {
      v.push_back(3);
      v.push_back(2);
      v.push_back(2);
    }
    if (a % 10 == 3) {
      v.push_back(3);
    }
    if (a % 10 == 2) {
      v.push_back(2);
    }
    a /= 10;
  }
  sort(v.begin(), v.end());
  reverse(v.begin(), v.end());
  for (long long i = 0; i < (long long)v.size(); i++) printf("%lld", v[i]);
  return 0;
}
