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>
def fact(n):
	if n==0:
		return 1
	return n*fact(n-1)

input()
n = list(input())
for i in range(len(n)):
	n[i]=int(n[i])
t = []
total = 1
for i in range(len(n)):
	if n[i] >= 7:
		total *= fact(n[i])//fact(7)
		n[i] = 1
		t.append(7)

for i in range(len(n)):
	if n[i] >= 5:
		total *= fact(n[i])//fact(5)
		n[i] = 1
		t.append(5)

for i in n:
	total *= fact(i)

while (total%3==0):
	total /= 6
	t.append(3)

while (total%2==0):
	total /= 2
	t.append(2)

for i in t:
	print(i, end = '')

print()