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>
def fact(n):
    if n==0:
        return 1
    return n*fact(n-1)

n = input()
digit = int(input())
f = int(1)
while digit!=0:
    f *= fact(digit%10)
    digit //= 10
lst = []
i = int(7)
while i>=3:
    k = int(0)
    while f%i==0:
        k = k+1
        f = f//i
        lst.append(i)
    while k>0:
        j = i-1
        while j>=2:
            f = f//j
            j = j-1
        k = k-1
    i = i-2
while f%2==0:
    f //= 2
    lst.append(2)
for i in range(0, len(lst)):
    print(lst[i], end="")
print("")