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:
n=int(input())
si=0;
for i in range(1,n+1):
    for k in range(1,101):
        if k%i==0 and k*i>n and k/i<n:
            si=1;a=k;b=i
            break         
if si==1:
    print(a,b)
else:
    print(-1)