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:
t=int(input())
found = False
a1=0
b1=0
for a in range(1,t+1):
    if not found:
        for b in range(1,a+1):
            if a % b==0 and a*b > t and a/b < t:
                found = True
                a1=a
                b1=b
                break
if found:
    print(a1,b1)
else:
    print(-1)