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())
l=[]
if n>3:
    if n%2==0:
        l.append(n)
        l.append(n//2)
    else:
        l.append(n-1)
        l.append((n-1)//2)
elif n==2 or n==3:
    l.append(2)
    l.append(2)
else:
    l.append(-1)
for j in l:
    print(j,end=" ")