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  math
n =int (input())
m = [int(x) for x in str (input())]
# print(m)
n = []
s = ''
k = 0
for i in m :
    if   i == 2 or i == 3 or i == 5 or i == 7 :
        n.append(i)

    if i == 4 or i == 6 or i == 8 or i ==9 :
        k = math.factorial(i)
        while(k != 1):
            # print(k)
            if k % math.factorial(7) == 0:
                n.append(7)
                k = k // math.factorial(7)
            if k % math.factorial(5) == 0:
                n.append(5)
                k = k // math.factorial(5)

            if k % 6 == 0:
                n.append(3)
                k = k // 6

            if k % 2 == 0:
                k =  k//2
                n.append(2)

n = sorted(n)[::-1]
for i in n:
    s += str(i)

print(s)





