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 main() {
  int n, m, i, j, s[8] = {0};
  char num[20], b;
  scanf("%d%c", &n, &b);
  for (i = 0; i < n; i++) {
    num[i] = getchar();
    if (num[i] == '3') {
      s[3]++;
    } else if (num[i] == '2') {
      s[2]++;
    } else if (num[i] == '4') {
      s[2] += 2;
      s[3]++;
    } else if (num[i] == '5') {
      s[5]++;
    } else if (num[i] == '6') {
      s[3]++;
      s[5]++;
    } else if (num[i] == '7') {
      s[7]++;
    } else if (num[i] == '8') {
      s[7]++;
      s[2] += 3;
    } else if (num[i] == '9') {
      s[7]++;
      s[3] += 2;
      s[2]++;
    }
  }
  for (i = 7; i > 1; i--) {
    if (s[i] != 0) {
      for (j = 0; j < s[i]; j++) {
        printf("%d", i);
      }
    }
  }
  printf("\n");
  return 0;
}
