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>
N=input()
A=raw_input()
answer = []


for val in A:   
    if(val == '2' or val == '3' or val == '5' or val == '7'):
        answer.append(val)
        
    elif(val == '4'):
        answer.append('3')
        for i in range(2):
            answer.append('2')

    elif(val == '6'):
        answer.append('5')
        answer.append('3')

    elif(val == '8'):
        answer.append('7')
        for i in range(3):
            answer.append('2')

    elif(val == '9'):
        answer.append('7')
        answer.append('2')
        for i in range(2):
            answer.append('3')
        

answer=sorted(answer,key=int,reverse=True)
print "".join(answer)
