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;
const int N = 2e5 + 10;
int n, a[N], num[N], cnt;
char s[N];
int main() {
  scanf("%d", &n);
  scanf("%s", s + 1);
  for (int i = 1; i <= n; i++) {
    if (s[i] <= '1') continue;
    if (s[i] == '2') num[2]++;
    if (s[i] == '3') num[3]++;
    if (s[i] == '4') num[2] += 2, num[3]++;
    if (s[i] == '5') num[5]++;
    if (s[i] == '6') num[5]++, num[3]++;
    if (s[i] == '7') num[7]++;
    if (s[i] == '8') num[7]++, num[2] += 3;
    if (s[i] == '9') num[7]++, num[2]++, num[3] += 2;
  }
  for (int i = 9; i >= 2; i--)
    for (int j = 1; j <= num[i]; j++) putchar(i + '0');
  return 0;
}
