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>
def create_number(number):
    digits=[]
    factorials={2:[2],3:[3],4:[3,2,2],5:[5],6:[5,3],7:[7],8:[2,2,2,7],9:[2,3,3,7]}

    while number>0:
        last_digit=number%10
        number=number//10
        if last_digit in factorials:
            cdigits=factorials[last_digit]
            for cdigit in cdigits:
                digits.append(cdigit)
    digits.sort()
    new_number=0
    power=0

    for index in range(len(digits)):
        digit=digits[index]
        new_number=new_number+digit*(10**power)
        power+=1
    result=new_number
    return result


digits_ammount=int(input())
number=int(input())
result=create_number(number)
print(result)