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())
b = 0
n = 0
a = 0
n1 = 1
n_nulevoe = 1
cococo = 0
while (n+1) != x:
    a = x - n
    while n1 <= a:
        b = n1
        if a % b != 0:
            n1 += 1
        elif a % b == 0:
            if a / b >= x:
                n1 += 1
            else:
                if a*b < x:
                    n1 += 1
                else:
                    cococo = 1
                    print(a, b)
                    break
    if cococo == 1:
        break
    else:
        n += 1
        b = n_nulevoe
        n1 = n_nulevoe
else:
    print(-1)