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())
a=0
b=0
c=0
for i in range(1,x+1):
	a=i
	for j in range(1,x+1):
		b=j
		if a%b==0 and a*b>x and a//b<x:
			print(a,b)
			c=1
			break
	if c==1:
		break
if c==0:
	print(-1)