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()
x = [int(i) for i in a]
for i in range(x.count(0)):
    x.remove(0)
for i in range(x.count(1)):
    x.remove(1)


for i in x:
    
    if i == 4:
        x.remove(i)
        x.insert(0,3)    
        x.insert(0,2)
        x.insert(0,2)
    elif i ==6:
        x.remove(i)
        x.insert(0,5)    
        x.insert(0,3)
    elif i==8:
        x.remove(i)
        x.insert(0,7)    
        x.insert(0,2)
        x.insert(0,2)
        x.insert(0,2)
    elif i==9:
        x.remove(i)
        x.insert(0,7)
        x.insert(0,3)
        x.insert(0,3)
        x.insert(0,2)
x.sort(reverse=True)

x = [str(i) for i in x]

print("".join(x))            