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>
vals = {
2:[2],
3:[3],
4:[2,2,3],
5:[5],
6:[5,3],
7:[7],
8:[7,2,2,2],
9:[7,3,3,2]
}
n = int(input())
a = input()
l = []
for ds in a:
	d = int(ds)
	if d!=0 and d!=1:
		l[len(l):] = vals[d]
l.sort(reverse=True)
x = "".join(map(str,l))
print(x)
 	 	 		 	 	 	   	 	 				   	 	