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(raw_input())
l=[]
for i in range(n):
    d=a%10
    a/=10
    if d & (d-1)==0 and d!=0 and d!=1 and d!=9 and d!=6:
        l.append(d-1)
        while d/2>0:
            l.append(2)
            d/=2
        continue
    if  d&(d-1)!=0 and d!=0 and d!=1 and d!=9 and d!=6:
        l.append(d)
        continue
    if d==9 and d!=6:
        l.append(7)
        l.append(3)
        l.append(3)
        l.append(2)
    if d==6:
        l.append(3)
        l.append(5)
l.sort()
c=0

for i in range(len(l)):
   if(l[len(l)-i-1]==1 or l[len(l)-i-1]==0):
       break
   c+=l[len(l)-i-1]
   c=c*10
print c/10