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 k[150];
bool cmp(int a, int b) { return a >= b; }
int main() {
  int n, i, temp, t;
  long long a;
  int number[10][15] = {{0}, {0},    {2}, {3},          {3, 2, 2},
                        {5}, {5, 3}, {7}, {7, 2, 2, 2}, {7, 2, 3, 3}};
  while (scanf("%d", &n) == 1) {
    t = 0;
    memset(k, 0, sizeof(k));
    cin >> a;
    while (a != 0) {
      temp = a % 10;
      if (temp != 0 && temp != 1) {
        for (i = 0; number[temp][i] != 0; i++) {
          k[t] = number[temp][i];
          t++;
        }
      }
      a = a / 10;
    }
    sort(k, k + t, cmp);
    for (i = 0; i < t; i++) printf("%d", k[i]);
    printf("\n");
  }
  return 0;
}
