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 math import factorial as fac
n = int(input())
s = input()
a = []
# ans, ans1 = 0, 0
# for i in s:
#     ans += fac(int(i))
for i in s:
    if(i == "2" or i == "3" or i == "5" or i == "7"):
        a.append(int(i))
    elif(i == "4"):
        a.extend([2, 2, 3])
    elif(i == "6"):
        a.extend([3, 5])
    elif(i == "8"):
        a.extend([2, 2, 2, 7])
    elif(i == "9"):
        a.extend([3, 3, 2, 7])
a.sort(reverse = True)
# print(a)
# for i in a:
#     ans1 += fac(int(i))

print("".join(str(e) for e in  a))
# print(ans, ans1)
