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>
class Solution:
    def __init__(self):
        self.n = int(input())
        self.a = int(input())

    def solve_and_print(self):
        a = [int(ai) for ai in str(self.a) if int(ai) > 1]
        ans = [2 for _ in range(a.count(2))] + [3 for _ in range(a.count(3))] + \
                [5 for _ in range(a.count(5))] + [7 for _ in range(a.count(7))]
        for _ in range(a.count(4)):
            ans.append(2)
            ans.append(2)
            ans.append(3)
        for _ in range(a.count(6)):
            ans.append(5)
            ans.append(3)
        for _ in range(a.count(8)):
            ans.append(7)
            for _ in range(3):
                ans.append(2)
        for _ in range(a.count(9)):
            ans.append(7)
            ans.append(3)
            ans.append(3)
            ans.append(2)
        ans.sort(reverse = True)
        print("".join(str(x) for x in ans))

if __name__ == "__main__":
    Solution().solve_and_print()