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())
test=False
if x==1:
    print("-1")
else:
    for i in range(2,x+1):
        for j in range(2,x+1):
            if (i*j>x) and (j%i==0) and (j/i<x):
                print(j," ",i);
                test=True
                break
        if test :
            break