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 PYTHON):

Solution:
'''
1088 A
'''

import os
flag = 0
n = input()
output = []
for i in range(1,n+1):
  for j in range(1,n+1):
    if(j>i):
        if(j%i==0 and j*i>n and j/i<n):
          flag=1
          output.append(j)
          output.append(i)
          break
    else:
        if(i%j==0 and i*j>n and i/j<n):
          flag=1
          output.append(j)
          output.append(i)
          break
if(flag==1):
  print(str(output[0])+" "+str(output[1]))
else:
  print(-1)