Find the middle element when the numbers in an $n \times n$ multiplication table are sorted in increasing order. It is assumed that $n$ is odd.
For example, the $3 \times 3$ multiplication table is as follows: $$
\begin{matrix}
1 & 2 & 3 \
2 & 4 & 6 \
3 & 6 & 9 \
\end{matrix}
$$ The numbers in increasing order are $[1,2,2,3,3,4,6,6,9]$ , so the answer is $3$ .
The only input line has an integer $n$ .
Print one integer: the answer to the task.