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 sys import stdin, stdout

n=int(stdin.readline())
s=list(stdin.readline())
s=s[:-1]

s=[int(i) for i in s]
ans={}
ans[2]=[2]
ans[3]=[3]
ans[4]=[2,2,3]
ans[5]=[5]
ans[6]=[3,5]
ans[7]=[7]
ans[8]=[2,2,2,7]
ans[9]=[3,3,2,7]
arr=[]
for i in range(len(s)):
    if(s[i]!=1 and s[i]!=0):
        arr+=ans[s[i]]


arr.sort(reverse=True)
for i in arr:
    stdout.write(str(i)+"")
