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>
list = [0] * 10
n=int(input())
s=str(input())
for ch in s:
    if ch == '2':
        list[2] = list[2] + 1
    elif ch == '3':
        list[3] = list[3] + 1
    elif ch == '4':
        list[3] = list[3] + 1
        list[2] = list[2] + 2
    elif ch == '5':
        list[5] = list[5] + 1
    elif ch == '6':
        list[3] = list[3] + 1
        list[5] = list[5] + 1
    elif ch == '7':
        list[7] = list[7] + 1
    elif ch == '8':
        list[2] = list[2] + 3
        list[7] = list[7] + 1
    elif ch == '9':
        list[2] = list[2] + 1
        list[3] = list[3] + 2
        list[7] = list[7] + 1
output = ""
num = 9
for item in list[::-1]:
    output = output + (str(num) * item)
    num = num - 1
print(output)