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>
from collections import Counter,defaultdict,deque
#alph = 'abcdefghijklmnopqrstuvwxyz'
#from math import factorial as fact
#import math

tt = 1#int(input())
#total=0
#n = int(input())

#n,m,k = [int(x) for x in input().split()]
for i in range(tt):
   n = int(input())
   s = input()
   d = defaultdict(int)
   for el in s:
      for i in range(2,int(el)+1):
         if i==9:           
            d[3]+=2
         elif i==8:
            d[2]+=3
         elif i==6:
            d[3]+=1
            d[2]+=1
         elif i==4:
            d[2]+=2
         else:
            d[i]+=1
   #print(d)
   ans =''
   while d[7]:
      ans+='7'
      d[7]-=1
      d[2]-=4
      d[3]-=2
      d[5]-=1
   while d[5]:
      ans+='5'
      d[5]-=1
      d[2]-=3
      d[3]-=1
   while d[3]:
      ans+='3'
      d[3]-=1
      d[2]-=1
   while d[2]:
      ans+='2'
      d[2]-=1
   print(ans)
      
      
      
