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>

n=int(input())

str1=input()
str2=""
for i in range(len(str1)):
	if(str1[i]=='2' or str1[i]=='3' or str1[i]=='5' or str1[i]=='7'):
		str2=str2+str1[i]
	elif str1[i]=='4':
		x="322"
		str2=str2+x
	elif str1[i]=='6':
		x="53"
		str2=str2+x
	elif str1[i]=='8':
		x="7222"
		str2=str2+x
	elif str1[i]=='9':
		x="7332"
		str2=str2+x
l2=[]
for i in str2:
	l2.append(int(i))
l2.sort(reverse=True)
for i in l2:
	print(i,end="")
