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
import string
import math
import sys
def array_int():
    return [int(i) for i in sys.stdin.readline().split()]
def vary(number_of_variables):
    if number_of_variables==1:
        return int(sys.stdin.readline())
    if number_of_variables>=2:
        return map(int,sys.stdin.readline().split()) 
def makedict(var):
    return dict(Counter(var))
mod=100000007
# sys.stdin=open('input.txt','r')
# sys.stdout=open('output.txt','w')
dic={'1':'','0':'','2':'2','3':'3','4':'322','5':'5','6':'53','7':'7','8':'7222','9':'7332'}
n=vary(1)
num=input()
ans=''
for i in num:
    ans+=dic[i]
ans=list(ans)
ans.sort(reverse=True)
for i in ans:
    print(i,end="")


    


    


    



