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())
Check=False
Stop=False
for i in range(1,X+1):
    for j in range(1,X+1):
        if i%j==0 and i*j>X and i/j<X:
            print(str(i)+" "+str(j))
            Check=True
            Stop=True
    if(Stop==True):
        break

if Check==False:
    print(str(-1))