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>
# python3
import sys, threading, os.path
import string
import collections, heapq, math, bisect

sys.setrecursionlimit(10 ** 6)
threading.stack_size(2 ** 27)


def factorial(n):
    if n == 0:
        return 1

    return n * factorial(n-1)


def transform(n):
    if n == 4:
        return "322"
    elif n == 6:
        return "53"
    elif n == 8:
        return "7222"
    elif n == 9:
        return "7332"
    else:
        return n


def main():
    if os.path.exists('in.txt'):
        input = open('in.txt', 'r')
    else:
        input = sys.stdin
    # --------------------------------INPUT---------------------------------
    n = list(map(int, input.readline().split()))
    st = str(input.readline().rstrip('\n'))

    res = ""

    for x in st:
        if int(x) <= 1:
            continue
        res += str(transform(int(x)))

    output = ''.join(map(str, sorted(res, reverse= True)))
    # -------------------------------OUTPUT----------------------------------
    if os.path.exists('out.txt'):
        open('out.txt', 'w').writelines(str(output))
    else:
        sys.stdout.write(str(output))


if __name__ == '__main__':
    main()
# threading.Thread(target=main).start()