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>
from sys import stdin

def readline():
    return stdin.readline().rstrip().split()

def ints(in_list):
    return (int(item) for item in in_list)

# Read-in
(n,) = [int(item) for item in readline()]
a = [int(stdin.read(1)) for _repeat in range(n)]

# pre-config
mappings = {
    0: [],
    1: [1],
    2: [2],
    3: [3],
    4: [3,2,2],
    5: [5],
    6: [5,3],
    7: [7],
    8: [7,2,2,2],
    9: [7,3,3,2],
}

mapped = []
for digit in a:
    mapped += mappings[digit]

out_list = [item for item in mapped if item > 1]
sorted_list = sorted(out_list, reverse = True)

out_str = ''
for item in sorted_list:
    out_str += '%d' % item

print(out_str)
