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:
x= int(input())

atv= False
num1= 0
num2= 0

for a in range(x, -1, -1):
    for b in range(x, -1, -1):
        if (1<=a<=x) and (1<=b<=x):
            if a%b==0:
                if a*b>x:
                    if a/b<x:
                        num1= a
                        num2= b
                        atv= True
                        break
    if atv==True:
        break
   
if num1==0:
    print(-1)

else:
    print(num1, num2)