Drazil is playing a math game with Varda.

Let's define <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/7020b94c48be2ee5b8eeca05f379c8911bb0e7c4.png" style="max-width: 100.0%;max-height: 100.0%;"/> for positive integer *x* as a product of factorials of its digits. For example, <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/6784d861d9a724d0aeddefcb00b7d0c3442ae586.png" style="max-width: 100.0%;max-height: 100.0%;"/>.

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. <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/7020b94c48be2ee5b8eeca05f379c8911bb0e7c4.png" style="max-width: 100.0%;max-height: 100.0%;"/> = <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/aa57e017a6c74d06b0a54bc47e3f6990e5af38c1.png" style="max-width: 100.0%;max-height: 100.0%;"/>.

Help friends find such number.
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.
def factorial(n):
	prod = 1 
	for i in range(1, n + 1):
		prod *= i 
	return prod 
import sys
n = int(sys.stdin.readline())
s = input()
if '1' not in s:
	print(s)
else:
	prod = 1 
	for i in range(n):
		prod *= factorial(int(s[i]))
	li = list(set(s))
	li.sort() 
	new_li = []
	for i in range(len(li) - 2, -1, -1):
		if li[i] != '1' and li[i] != '0' and prod != 1:
			fac = factorial(int(li[i]))
			while (prod % fac == 0):
				prod //= fac 
				new_li.append(li[i])
	for i in new_li:
		print(i, end = '')


