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
def fun(a):
    for i in range(1,p+1):
        for j in range(p,0,-1):
            if(((i%j)==0)and((i*j)>a)and((i/j)<a)):
                print(i,j)
                return
    print("-1")
p=int(input())
fun(p)