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>
a=input()
n=list(raw_input())
n= map(int,n)
dic={}
dic[1]='1'
dic[2]='2'
dic[3]='3'
dic[4]='322'
dic[5]='5'
dic[6]='53'
dic[7]='7'
dic[8]='7222'
dic[9]='7332'
s=""
for i in n:
	if i!=0 and i!=1:
		s=s+dic[i]
d=map(int,list(s))
d.sort()
s=map(str,d[::-1])
print ''.join(s)