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>
import sys
input = sys.stdin.readline

'''

'''

def get_p_factors(num):
    res = []
    for d, p in [(factorial(7), 7), (factorial(5), 5), (factorial(3), 3), (factorial(2), 2)]:
        while num % d == 0:
            #print(num, res)
            num //= d
            res.append(p)
    return int("".join(map(str, res)))

from math import factorial
def F(str_num):
    res = 1
    for d in str_num:
        res *= factorial(int(d))
    return res


input()
a = input().rstrip()
print(get_p_factors(F(a)))
