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=int(input())
li=[]

for i in range(n):
    if  a%10==7 or a%10==3 or a%10==2 :
        li.append(a%10)
    elif a%10==9:
        li.append(2)
        li.append(3)
        li.append(3)
        li.append(7)
    elif a%10==8:
        li.append(2)
        li.append(2)
        li.append(2)
        li.append(7)
        
    elif a%10==6:
        li.append(3)
        li.append(5)
       
    elif a%10==5:
        li.append(5)
        
    elif a%10==4:
        li.append(2)
        li.append(2)
        li.append(3)
       
    elif a%10==3:
        li.append(3)
        
    elif a%10==2:
        li.append(2)
        
    a//=10
li.sort(reverse=True)

for i in range(len(li)):
    print(li[i],end="")