#include <bits/stdc++.h>
using namespace std;
int fact[11] = {1, 1, 2, 6, 24, 120, 720, 5040, 40320, 362880};
int main() {
  int primes[10] = {2, 3, 5, 7};
  int count[10] = {0};
  int mapp[10] = {0};
  int n;
  char a[20];
  scanf("%d", &n);
  scanf("%s", &a);
  unsigned long long int fa = 1;
  int i = 0, twos = 0, threes = 0;
  while (a[i] == '0') i++;
  while (i < n) {
    if (a[i] == '7' || a[i] == '5') mapp[a[i] - '0']++;
    if (a[i] == '6')
      mapp[5]++, twos++, threes++;
    else if (a[i] == '8')
      mapp[7]++, twos += 3;
    else if (a[i] == '9')
      twos += 3, threes += 2, mapp[7]++;
    else if (a[i] == '4')
      twos += 3, threes++;
    else if (a[i] == '3')
      threes++, twos++;
    else if (a[i] == '2')
      twos++;
    i++;
  }
  for (i = 9; i >= 5; i--) {
    while (mapp[i] != 0) {
      printf("%d", i);
      mapp[i]--;
    }
  }
  while (threes != 0) {
    printf("3");
    threes--;
    twos--;
  }
  while (twos != 0) {
    printf("2");
    twos--;
  }
  printf("\n");
  return 0;
}

### Prompt

Please provide a CPP coded solution to the problem described below:

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>

### Response

```cpp
#include <bits/stdc++.h>
using namespace std;
int fact[11] = {1, 1, 2, 6, 24, 120, 720, 5040, 40320, 362880};
int main() {
  int primes[10] = {2, 3, 5, 7};
  int count[10] = {0};
  int mapp[10] = {0};
  int n;
  char a[20];
  scanf("%d", &n);
  scanf("%s", &a);
  unsigned long long int fa = 1;
  int i = 0, twos = 0, threes = 0;
  while (a[i] == '0') i++;
  while (i < n) {
    if (a[i] == '7' || a[i] == '5') mapp[a[i] - '0']++;
    if (a[i] == '6')
      mapp[5]++, twos++, threes++;
    else if (a[i] == '8')
      mapp[7]++, twos += 3;
    else if (a[i] == '9')
      twos += 3, threes += 2, mapp[7]++;
    else if (a[i] == '4')
      twos += 3, threes++;
    else if (a[i] == '3')
      threes++, twos++;
    else if (a[i] == '2')
      twos++;
    i++;
  }
  for (i = 9; i >= 5; i--) {
    while (mapp[i] != 0) {
      printf("%d", i);
      mapp[i]--;
    }
  }
  while (threes != 0) {
    printf("3");
    threes--;
    twos--;
  }
  while (twos != 0) {
    printf("2");
    twos--;
  }
  printf("\n");
  return 0;
}

```