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 arr[20];
int cnt[15] = {0};
int ans[15] = {0};
int main() {
  int n;
  scanf("%d", &n);
  scanf("%s", arr);
  for (int i = 0; i < n; i++) {
    cnt[arr[i] - '0']++;
  }
  for (int i = 8; i >= 2; i--) cnt[i] += cnt[i + 1];
  ans[2] += cnt[2];
  ans[3] += cnt[3];
  ans[2] += 2 * cnt[4];
  ans[5] += cnt[5];
  ans[2] += cnt[6];
  ans[3] += cnt[6];
  ans[7] += cnt[7];
  ans[2] += 3 * cnt[8];
  ans[3] += 2 * cnt[9];
  while (ans[7]--) {
    printf("%d", 7);
    ans[2] -= 4;
    ans[3] -= 2;
    ans[5]--;
  }
  while (ans[5]--) {
    printf("%d", 5);
    ans[2] -= 3;
    ans[3]--;
  }
  while (ans[3]--) {
    printf("%d", 3);
    ans[2]--;
  }
  while (ans[2]--) printf("%d", 2);
  puts("");
  return 0;
}
