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())
h = 0
mx = 1
for i in range(1, x+1):
    j = i
    while j < x+1:
        if i*j > x and j%i == 0 < x and j/i < x:
            #if mx < i*j
            print(j,i)
            h = 1
            break
        j += i   
    if h == 1:
        break
        
if h == 0:
    print(-1)