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 sys import stdin,stdout,setrecursionlimit,maxint,exit
#setrecursionlimit(2*10**5)
def listInput():
 return map(long,stdin.readline().split())
def printBS(li):
 for i in xrange(len(li)-1):
  stdout.write("%d "%li[i])
 stdout.write("%d\n"%li[-1])
def sin(): return stdin.readline().rstrip()
no=input()
n=sin()
dic={2:"2",3:"3",4:"223",5:"5",6:"53",7:"7",8:"2227",9:"2337"}
ans=""
for i in n:
 if i not in ("0","1"):
  ans+=dic[int(i)]
ans=list(ans)
ans.sort()
ans.reverse()
print "".join(ans)