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())
if(n==1):
	print(-1)
else:
	l=[]
	for i in range(2,n+1):
		a=i
		for j in range(i,n+1):
			if(a*j>n):
				if(j%a==0):
					l=[j,a]
					break
		if(len(l)==2):
			break
	if(len(l)==2):
		print(l[0],l[1])
	else:
		print(-1)