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>
'''input
3
555
'''
n = int(input())
s = input()
d = {7:0, 5:0, 3:0, 2:0}
for x in s:
	if x == '2':
		d[2] += 1
	elif x == '3':
		d[3] += 1
	elif x == '4':
		d[3] += 1
		d[2] += 2
	elif x == '5':
		d[5] += 1
	elif x == '6':
		d[5] += 1
		d[3] += 1
	elif x == '7':
		d[7] += 1
	elif x == '8':
		d[7] += 1
		d[2] += 3
	elif x == '9':
		d[7] += 1
		d[3] += 2
		d[2] += 1
for x in [7, 5, 3, 2]:
	print(str(x) * d[x], end = "")

















  