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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