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 solve(n,s):

    ans = []
    for i in range(n):
        if s[i] == "0" or s[i] == "1":
            continue
        ans.append(s[i])

    for i in range(len(ans)):
        ans[i] = dict.get(int(ans[i]))

    ans = "".join(map(str,ans))
    ans = list(ans)
    ans.sort(reverse=True)
    print("".join(map(str,ans)))





if __name__ == '__main__':
    dict = {}
    ar = [i for i in range(0,10)]
    dict = dict.fromkeys(ar,None)

    dict[0] = 0
    dict[1] = 0
    dict[2] = 2
    dict[3] = 3
    dict[4] = 322
    dict[5] = 5
    dict[6] = 53
    dict[7] = 7
    dict[8] = 7222
    dict[9] = 7332


    n = int(input())
    s = input()
    solve(n,s)