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>
import math

hsh = {2:[2], 3:[3], 4:[2,2,3], 5:[5], 6:[5,3], 7:[7], 8:[7,2,2,2], 9:[7,3,3,2]}

if __name__ == '__main__':
	x = input()
	a = [int(x) for x in raw_input()]
	ls=[]
	for i in a:
		if i > 1:
			ls.extend(hsh[i])
	ls.sort(reverse=True)
	st = ""
	for i in ls:
		st = st+str(i)
	print st
