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())
condition = False
for a in range(1,x+1):
    for b in range(a,x+1):
        if a*b > x and float(a)/float(b) < x and a % b == 0:
            print(str(a) + " "+ str(b),end ="")
            condition = True
            break
    if condition == True:
        break
if condition == False:
    print(-1,end ="")