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 solve(n):
    if(n==1):
        return -1
    else:
        for i in range(1,n+1):
            for j in range(1,n+1):
                
                if(i%j==0 and (i*j)>n and (i//j)<n):
                    return ' '.join(map(str,(i,j)))
        return -1

n=int(input())
print(solve(n))