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>
import math

if __name__ == '__main__':
    n = int(input())
    s = input()
    a = [int(x) for x in s if x != '0']
    res = []
    for x in a:
        if x == 4:
            res.extend([2, 2, 3])
        elif x == 8:
            res.extend([2, 2, 2, 7])
        elif x == 6:
            res.extend([3, 5])
        elif x==9:
            res.extend([7,3,3,2])
        elif x != 1 and x != 0:
            res.append(x)
    res.sort(reverse=True)
    print(''.join([str(x) for x in res]))