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())
flag = 0
for _ in range((x//2),x+1) :
    for i in range(1,(x+1)):
        if(_* i > x and _ // i < x and _ % i == 0):
            print( _ , i)
            flag = 1
            break
    if flag == 1:
        break
#print(_ + i)
if flag == 0:
    print("-1")