A. Ehab and another construction problem
time limit per test
1 second
memory limit per test
256 megabytes
input
standard input
output
standard output

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 $$$b$$$).
  • $$$a \cdot b>x$$$.
  • $$$\frac{a}{b}<x$$$.
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).

Examples
Input
10
Output
6 3
Input
1
Output
-1