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;
char buf[20];
int n;
int cnts[10] = {0};
void factor(int t) {
  for (int i = 2; i <= 9; i++) {
    while (t % i == 0) {
      t /= i;
      cnts[i]++;
    }
  }
}
void defactor(int t) {
  for (int i = 2; i <= 9; i++) {
    while (t % i == 0) {
      t /= i;
      cnts[i]--;
    }
  }
}
int main() {
  scanf("%d", &n);
  scanf("%s", buf);
  for (int i = 0; i < n; i++) {
    int t = buf[i] - '0';
    for (int i = 2; i <= t; i++) {
      factor(i);
    }
  }
  vector<int> ans;
  for (int i = 9; i >= 2; i--) {
    while (cnts[i] > 0) {
      for (int j = 2; j <= i; j++) defactor(j);
      ans.push_back(i);
    }
  }
  for (int x : ans) printf("%d", x);
  printf("\n");
}
