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 f(n):
	if n==0:
		return 1
	if n==1:
		return 1;
	return n*f(n-1)
n=int(input())
n=int(input())
m=1
while n>0:
	m*=f(n%10)
	n//=10
s=""
while m%7==0:
	s+="7"
	m//=f(7)
while m%5==0:
	s+="5"
	m//=f(5)
while m%3==0:
	s+="3"
	m//=f(3)
while m%2==0:
	s+="2"
	m//=f(2)
print(s)