#include <bits/stdc++.h>
using namespace std;
template <class T>
T min3(T a, T b, T c) {
  return min(a, min(b, c));
};
template <class T>
T max3(T a, T b, T c) {
  return max(a, max(b, c));
};
void openFile() { freopen("/home/khaihanhdk/devplace/a.inp", "r", stdin); }
int sl[10000];
void pt(int x) {
  if (x == 2)
    sl[2]++;
  else if (x == 3)
    sl[3]++;
  else if (x == 4) {
    sl[3]++;
    sl[2] += 2;
  } else if (x == 5)
    sl[5]++;
  else if (x == 6) {
    sl[5]++;
    sl[3]++;
  } else if (x == 7) {
    sl[7]++;
  } else if (x == 8) {
    sl[7]++;
    sl[2] += 3;
  } else if (x == 9) {
    sl[7]++;
    sl[3] += 2;
    sl[2]++;
  }
}
char s[10000];
int main() {
  int n;
  scanf("%d", &n);
  scanf("%s", &s);
  for (int i = 0; i < n; i++) pt(s[i] - '0');
  for (int i = 9; i >= 2; i--)
    for (int j = 0; j < sl[i]; j++) printf("%d", i);
}

### Prompt

Create a solution in Cpp for the following problem:

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;
template <class T>
T min3(T a, T b, T c) {
  return min(a, min(b, c));
};
template <class T>
T max3(T a, T b, T c) {
  return max(a, max(b, c));
};
void openFile() { freopen("/home/khaihanhdk/devplace/a.inp", "r", stdin); }
int sl[10000];
void pt(int x) {
  if (x == 2)
    sl[2]++;
  else if (x == 3)
    sl[3]++;
  else if (x == 4) {
    sl[3]++;
    sl[2] += 2;
  } else if (x == 5)
    sl[5]++;
  else if (x == 6) {
    sl[5]++;
    sl[3]++;
  } else if (x == 7) {
    sl[7]++;
  } else if (x == 8) {
    sl[7]++;
    sl[2] += 3;
  } else if (x == 9) {
    sl[7]++;
    sl[3] += 2;
    sl[2]++;
  }
}
char s[10000];
int main() {
  int n;
  scanf("%d", &n);
  scanf("%s", &s);
  for (int i = 0; i < n; i++) pt(s[i] - '0');
  for (int i = 9; i >= 2; i--)
    for (int j = 0; j < sl[i]; j++) printf("%d", i);
}

```