Problem: Given an integer x, find 2 integers a and b such that: 

  * 1 ≤ a,b ≤ x 
  * b divides a (a is divisible by b). 
  * a ⋅ b>x. 
  * a/b<x. 

Input

The only line contains the integer x (1 ≤ x ≤ 100).

Output

You should output two integers a and b, satisfying the given conditions, separated by a space. If no pair of integers satisfy the conditions above, print "-1" (without quotes).

Examples

Input

10


Output

6 3

Input

1


Output

-1

Solution (in PYTHON3):

Solution:
# cook your dish here
x=int(input())
a=1
z=0
k=0
while a<=x and k==0:
    b=1
    
    while b<=x :
      
        if a%b==0 :
            if a*b>x:
                if a/b<float(x):
                    print(a,"",b)
                    z=1
                    k=1
                    break
                else:
                    b=b+1
                    
                    continue
                    
            else:
                b=b+1
                
                continue
        else:
            b=b+1
            continue
    a=a+1    
if z==0:
    print('-1')