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>
# coding=utf-8


if __name__ == '__main__':
    n = int(input())
    a = str(input())
    a = a.replace('0', '').replace('1', '')
    refer_dict = {'2': '2', '3': '3', '4': '322', '5': '5', '6': '53', '7': '7', '8': '7222', '9': '7332'}
    value = ''
    for i in a:
        value += refer_dict[i]
    temp_list = list(value)
    temp_list.sort(reverse=True)
    print(''.join(temp_list))
