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>
r=lambda:map(int,raw_input().split())
n=input()
r=[]
for e in map(int,raw_input()):
        if e == 4:
            r+=[2,2,3]
        elif e==8:
            r+=[7,2,2,2]
        elif e==6:
            r+=[5,3]
        elif e==9:
            r+=[7,3,3,2]
        elif e>1:
            r+=[e]
print ''.join(map(str, sorted(r,reverse=True)))