codeforces#P1088A. Ehab and another construction problem

Ehab and another construction problem

Description

Given an integer $x$, find 2 integers $a$ and $b$ such that:

  • $1 \le a,b \le x$
  • $b$ divides $a$ ($a$ is divisible by $b$).
  • $a \cdot b>x$.
  • $\frac{a}{b}<x$.

The only line contains the integer $x$ $(1 \le x \le 100)$.

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).

Input

The only line contains the integer $x$ $(1 \le x \le 100)$.

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).

Samples

10

6 3
1

-1