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>
d = {'0':"",'1':"",'2':"2",'3':"3",'4':"322",'5':"5",'6':"53",'7':"7",'8':"7222",'9':"7332"}
res = ""
n = input()
temp = raw_input()
s = ""
j = 0
while j < n and temp[j] == "0":
	j += 1
while j < n:
	s += temp[j]
	j += 1
	
if s == "":
	print 0
else:	
	for c in s:
		res += d[c]

	x = []
	for c in res:
		x.append(c)
	x.sort(reverse = True)
	res = ""
	for c in x:
		res += c 
	print res
	
