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>
# cook your dish here



dic = { "2" : "2" , "3" : "3" , "4" : "322" , "5" : "5" , "6" : "53" , "7" : "7" , "8" : "7222" , "9" : "7332" }
n = int(input())
s = list(input())
#print(s)
res = []
for i in s:
    if i in dic:
        res.extend(list(dic[i]))
res.sort()
res.reverse()
print("".join(res))