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;
char s[505];
int t[505];
int main() {
  int n;
  scanf("%d%s", &n, s + 1);
  for (int i = 1; i <= n; i++) {
    int x = s[i] - '0';
    if (x == 4)
      t[3]++, t[2] += 2;
    else if (x == 6)
      t[5]++, t[3]++;
    else if (x == 8)
      t[7]++, t[2] += 3;
    else if (x == 9)
      t[7]++, t[3] += 2, t[2]++;
    else
      t[x]++;
  }
  for (int i = 9; i >= 2; i--) {
    for (int j = 1; j <= t[i]; j++) {
      printf("%d", i);
    }
  }
  printf("\n");
  return 0;
}
