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>
# coding =utf-8
n = int(input())
s = str(raw_input())
p =[]
for i in s:
	if i=='1':
		continue
	if i=='2':
		p.append(2)
	if i=='3':
		p.append(3)
	if i=='4':
		p.append(3)
		p.append(2)
		p.append(2)
	if i=='5':
		p.append(5)
	if i=='6':
		p.append(5)
		p.append(3)
	if i=='7':
		p.append(7)
	if i=='8':
		p.append(7)
		p.append(2)
		p.append(2)
		p.append(2)
	if i=='9':
		p.append(7)
		p.append(3)
		p.append(3)
		p.append(2)
p.sort(reverse=True)
stringnow =''
for i in p:
	stringnow = stringnow +str(i)
print stringnow
	