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:
if __name__== "__main__":
    n=int(input())
    a=1
    f=False
    b=1
    for i in range(1,n+1):
        a=i
        for j in  range(1,n+1):
            b=j
            if(a%b==0 and a*b>n and a/b<n):
                f=True
                break
        if f:
            break
        
    if(f):
        print(a,b)
    else:
        print(-1)