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:
"""
NTC here
"""
from sys import setcheckinterval,stdin
setcheckinterval(1000)

iin=lambda :int(stdin.readline())
lin=lambda :list(map(int,stdin.readline().split()))

x=iin()

for i in range(1,x+1):
    for j in range(1,x+1):
        if i%j==0:
            if i*j>x and i//j<x:
                print(i,j);exit()
print(-1)