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>
import sys
n=input()

s=raw_input()
val={}
val['6']='53'
val['8']='2227'
val['4']='322'
val['9']='2337'

ans=[]
for i in range(0,len(s)):
    if (s[i]=='6' or s[i]=='8' or s[i]=='4' or s[i]=='9'):
        ans.append(val[s[i]])
    else:
        ans.append(s[i])

l=[]
for i in ans:
    for j in i :
        if(j!='1' and i!='0'):
            l.append(j)

l.sort()
l.reverse()

print ''.join(l)
