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:
a = int(input())
t=0
for i in range(1,a+1):
    if(t==9):
        break
    for j in range(1, a+1):
        if(j%i==0)and(j*i>a)and(j/i<a):
            print(j,end=" ")
            print(i,end=" ")
            t=9
            break
if(t!=9):
    print("-1")