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:
x=int(raw_input())

if x==1:
    print -1
    exit(0)

if x==2 or x==3:
    print "2 2"
    exit(0)

if x==4:
    print "4 2"
    exit(0)

if x%2==0:
    print str(x), str(int(x/2))

else:
    print str(x-1), str(int((x-1)/2))