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>
int buc[11];
void add_n(int n) {
  switch (n) {
    case 9:
      buc[3] += 2;
      buc[2]++;
      buc[7]++;
      break;
    case 8:
      buc[2] += 3;
    case 7:
      buc[7]++;
      break;
    case 6:
      buc[3]++;
    case 5:
      buc[5]++;
      break;
    case 4:
      buc[2] += 2;
    case 3:
      buc[3]++;
      break;
    case 2:
      buc[2]++;
  }
}
int main(void) {
  char n[20];
  char *str;
  int i, j;
  int num[20];
  fgets(n, 20, stdin);
  fgets(n, 20, stdin);
  str = n;
  while ((*str) >= '0' && (*str) <= '9') {
    add_n((*str) - '0');
    str++;
  }
  for (i = 7; i >= 2; i--) {
    if (buc[i] > 0) {
      for (j = 1; j <= buc[i]; j++) {
        fputc('0' + i, stdout);
      }
    }
  }
  fputc('\n', stdout);
  return 0;
}
