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>
b =""
n4 = "322" 
n6 = "53"
n8 = "7222"
n9 = "7332"
n = int(input())
a = input()
for i in range(n):
    num = int(a[i])
    if num > 1:
        if num == 4:
            b += n4
        elif num == 6:
            b += n6
        elif num == 8:
            b += n8
        elif num == 9:
            b += n9
        else:
            b += a[i]


aux = sorted(b, reverse = True)
b = "".join(aux)
print(b)