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())
flag=0
for i in range(1,t+1):
    if flag!=1:
        for j in range(1,t+1):
            if flag!=1:
                if i%j == 0:
                    if i*j>t:
                        if i%j < t:
                            a,b = i,j
                            flag=1
if flag==1:
    print(a,b)
else:
    print("-1")