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>
ka = {
    '0':[],
    '1':[],
    '2':[2],
    '3':[3],
    '4':[3,2,2],
    '5':[5],
    '6':[5,3],
    '7':[7],
    '8':[7,2,2,2],
    '9':[7,3,3,2]
}

n=int(input())
l=input()
d=[]
for i in l:
    d=d+ka[i]
d.sort(reverse=True)
for i in d:
    print(i,end='')
print()
