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 -*-
import sys

def some_func():
    """
    """

    n = input()
    n_str = raw_input()
    temp = {"2":0,"3":0,"5":0,"7":0}
    for v in n_str:
        if v=="2":
            temp["2"] +=1
        elif v=="3":
            temp["3"] +=1
        elif v=="4":
            temp["2"] +=2
            temp["3"] +=1
        elif v=="5":
            temp["5"] +=1
        elif v=="6":
            temp["3"] +=1
            temp["5"] +=1
        elif v=="7":
            temp["7"] +=1
        elif v=="8":
            temp["2"] +=3
            temp["7"] +=1
        elif v=="9":
            temp["7"] +=1
            temp["3"] +=2
            temp["2"] +=1
    print "7"*temp["7"]+"5"*temp["5"]+"3"*temp["3"]+"2"*temp["2"]




if __name__ == '__main__':
    some_func()




