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>
size = input()
num = sorted(map(int, list(raw_input())))[::-1]

while 0 in num:
	num.remove(0)
while 1 in num:
	num.remove(1)
while 9 in num:
	if 4 in num:
		num.extend([3,3,3,8])
		num.remove(9)
		num.remove(4)
	else:
		num.extend([2,3,3,7])
		num.remove(9)
while 8 in num:
	num.extend([2,2,2,7])
	num.remove(8)
while 6 in num:
	num.extend([3,5])
	num.remove(6)
while 4 in num:
	num.extend([2,2,3])
	num.remove(4)

print ''.join(map(str,sorted(num)[::-1]))