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 = int(input())
arr = [int(x) for x in list(input())]
res = []

switcher = {
    4: [2, 2, 3],
    6: [3, 5],
    8: [2, 2, 2, 7],
    9: [3, 3, 2, 7]
}
spnums = [2,3,5,7]

for num in arr:
    if num in spnums:
        res.append(num)
    elif num is not 0 and num is not 1:
        # number must be 4, 6, or 8
        for item in switcher.get(num):
            res.append(item)

res.sort(reverse = True)
print(*res, sep = "")
