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:
x= int(input())
flag = False
if x==3:
     print("3 3")
elif x==2:
     print("2 2")
else:
     flag = False
     for j in range(1,x+1):
          for i in range(j+1,x+1):
               if (i*j>x) and (i%j==0) and (i/j<x):
                    print(i,j)
                    flag = True
                    break
          if flag:
               break
     if not flag:
          print(-1)