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())
s=input()
s1=""
for i in range(0,s.__len__()):
	if s[i]=='0' or s[i]=='1':
		continue
	if s[i]!='4' and s[i]!='6' and s[i]!='8' and s[i]!='9':
		s1=s1+s[i]
	else:
		if s[i]=='4':
			s1=s1+'223'
		elif s[i]=='6':
			s1=s1+'53'
		elif s[i]=='8':
			s1=s1+'2227'
		else:
			s1=s1+'3327'
l=[]
for x in range(0,s1.__len__()):
	l.append(s1[x])
l.sort()
l.reverse()
for x in l:
	print(x,end="")
print()