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 MAXN = 2333333;
int n, m, q, ans[MAXN], num[20][100];
char c[2333];
int main() {
  scanf("%d", &n);
  scanf("%s", c);
  int l = strlen(c);
  num[1][0] = 0;
  num[0][0] = 0;
  num[2][0] = 1;
  num[2][1] = 2;
  num[3][0] = 1;
  num[3][1] = 3;
  num[4][0] = 3;
  num[4][1] = 3;
  num[4][2] = 2;
  num[4][3] = 2;
  num[5][0] = 1;
  num[5][1] = 5;
  num[6][0] = 2;
  num[6][1] = 5;
  num[6][2] = 3;
  num[7][0] = 1;
  num[7][1] = 7;
  num[8][0] = 4;
  num[8][1] = 7;
  num[8][2] = 2;
  num[8][3] = 2;
  num[8][4] = 2;
  num[9][0] = 4;
  num[9][1] = 7;
  num[9][2] = 3;
  num[9][3] = 3;
  num[9][4] = 2;
  for (int i = 0; i < l; i++) {
    int now = c[i] - '0';
    for (int j = 1; j <= num[now][0]; j++) ans[++ans[0]] = num[now][j];
  }
  sort(ans + 1, ans + 1 + ans[0]);
  for (int i = ans[0]; i >= 1; i--) printf("%d", ans[i]);
  return 0;
}
