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:
inp = int(input())
not_possible=1
for a in range(1,inp+1):
    for b in range(1,a+1):
        temp=0
        if a%b==0:
            temp=temp+1
        if a*b>inp:
            temp=temp+1
        if a/b<inp:
            temp=temp+1
        if temp == 3:
            print(a,b)
            not_possible=0
            break
    if not_possible==0 :
        break
if not_possible==1:
    print(-1)