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>
n = int(input())
a = input()
b = []
for i in range(n):
    temp = int(a[i])
    if temp != 1:
        b.append(temp)
b.sort()
num = b.count(2)
c = []
for i in range(len(b)):
    if b[i] == 2:
        continue
    elif b[i] == 3 or b[i] == 5 or b[i] == 7:
        c.append(b[i])
    elif b[i] == 4:
        c.append(3)
        num += 2
    elif b[i] == 6:
        if num > 0:
            c.append(3)
            c.append(5)
        else:
            c.append(5)
            c.append(3)
    elif b[i] == 8:
        c.append(7)
        num += 3
    elif b[i] == 9:
        c.append(3)
        c.append(3)
        c.append(7)
        num += 1
if num > 0:
    for i in range(num):
        c.append(2)
c.sort(reverse=True)
for item in c:
    print(item,end="")
