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(raw_input())
a = [int(x) for x in raw_input()]

b = []

for i in range(n):
    if a[i] == 2:
        b.append(2)
    elif a[i] == 3:
        b.append(3)
    elif a[i] == 4:
        b.append(3)
        b.append(2)
        b.append(2)
    elif a[i] == 5:
        b.append(5)
    elif a[i] == 6:
        b.append(3)
        b.append(5)
    elif a[i] == 7:
        b.append(7)  
    elif a[i] == 8:
        b.append(7)
        b.append(2)
        b.append(2)
        b.append(2)
    elif a[i] == 9:
        b.append(7)
        b.append(3)
        b.append(3)
        b.append(2)

b.sort()
b.reverse()
x = ''
for i in range(len(b)):
    x = x + str(b[i])
    
print x