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 -*-
"""
Created on Mon May  4 22:51:50 2020

@author: Bilel Kanoun
"""

def Transfrom(s):
    if (s=='0' or s=='1'):
        out=""
    elif (s=='4'):
        out="322"
    elif (s=='6'):
        out="53"
    elif (s=='8'):
        out="7222"
    elif (s=='9'):
        out="7332"
    else:
        out=s
    
    return out

if __name__=='__main__':
    n = int(input())
    a=input()
    
    res=""
    for i in range(n):
        res+=Transfrom(a[i])

print("".join(sorted(res)[::-1]))