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>
__author__ = 'Rajan'


n = int(input())

l = [
    [],
    [],
    [2],
    [3],
    [3,2,2],
    [5],
    [5,3],
    [7],
    [7,2,2,2],
    [7,3,3,2]
]

s = list(input())

al = []

for k in s:
    al.append(l[int(k)])

#al = sorted(al,reverse=True)
#print(al)
ans = ""
for k in al:
    for i in k:
        ans+=str(i)

ans = ''.join(sorted(ans,reverse=True))
print(ans)