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:
def force(x):
  if (x < 1):
    return
  else:
    for a in range(1,x+1):
      b = 2;
      while (b <= x):
        if (a%b == 0):
          condition2 = (a*b) > x
          condition3 = (a/b) < x
          if (condition2 and condition3):
            print(a,b)
            return
        b += 1;
  print(-1)
  return

x = int(input())
force(x)