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())
m=0
for i in range(x,1,-1):
    for j in range(2,i+1,1):
        if i%j==0:
           if i*j>x:
              if i/j<x:
                 m=1
                 break
    if m==1:
        break;
if m==1:
	print(i,j)
else: print(-1)