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>
from sys import stdin,stdout
input = stdin.readline
def write(n,sep="\n"):
	stdout.write(str(n))
	stdout.write(sep)
def gil():
	return list(map(int, input().split()))
	
n = int(input())
a = input().strip()
ans = ""
s = ["","","2","3","322","5","53","7","7222","7332"]
for i in a:
	ans += s[int(i)]
ans = [int(i) for i in ans]
ans.sort(reverse=True)
x = ""
for i in ans:
	x += str(i)
print(x)
