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>
n, a = input(), input()
res = []
for let in a:
	if let == '2':
		res += [2]
	elif let == '3':
		res += [3]
	elif let == '4':
		res += [2, 2, 3]
	elif let == '5':
		res += [5]
	elif let == '6':
		res += [5, 3]
	elif let == '7':
		res += [7]
	elif let == '8':
		res += [7, 2, 2, 2]
	elif let == '9':
		res += [7, 3, 3, 2]
res.sort(reverse = True)
print("".join(str(x) for x in res))
