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>
l=input()
sr=raw_input()
list=[]
for i in range (l):
	if sr[i]=='2' or sr[i]=='5' or sr[i]=='7' or sr[i]=='3':
		list.append((int(sr[i])))
	elif sr[i]=='4':
		list.extend((2,2,3))
	elif sr[i]=='6':
		list.extend((3,5))
	elif sr[i]=='8':
		list.extend((2,2,2,7))
	elif sr[i]=='9':
		list.extend((3,3,2,7))
list.sort()
import sys
st=''
for i in range(len(list),0,-1):
	st=st+str(list[i-1])

print st
