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>
from collections import Counter
input()
s=raw_input()
s=Counter(s)
def myadd(x,k):
	if x in s:
		s[x]+=k
	else:
		s[x]=k
if'9'in s:
	myadd('7',s['9'])
	myadd('3',s['9']*2)
	myadd('2',s['9'])
	del s['9']
if'8'in s:
	myadd('7',s['8'])
	myadd('2',s['8']*3)
	del s['8']
if'6'in s:
	myadd('5',s['6'])
	myadd('3',s['6'])
	del s['6']
if'4'in s:
	myadd('3',s['4'])
	myadd('2',s['4']*2)
	del s['4']
if'1'in s:
	del s['1']
if'0'in s:
	del s['0']
l=[]
for a,b in s.items():
	l+=[a]*b
l.sort(reverse=True)
print''.join(l)