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>
four = [3, 2, 2]
six = [5, 3]
eight = [7, 2, 2, 2]
nine = [7, 3, 3, 2]
ln = int(input())
n = int(input())
l = []
while(n > 0):
    dig = n % 10
    n //= 10
    if dig == 4:
        l += four
    elif dig == 6:
        l += six
    elif dig == 8:
        l += eight
    elif dig == 9:
        l += nine
    elif dig != 1 and dig != 0:
        l.append(dig)

l.sort(reverse = True)
ans = ""
for i in range(len(l)):
    ans += str(l[i])
print(ans)
