H. One Two-One Chips (Extreme version)
time limit per test
1 second
memory limit per test
256 megabytes
input
standard input
output
standard output

A game invented by Marckess became popular last Donald Knuth Contest. Each person chooses a point in space, and chips will appear in the space. The closest person to a chip will receive one, while the farthest person from the others will lose one. The second closest person will receive two chips, and the second farthest will lose two chips.

However, Tony, Fabian, and Dani's team has obtained relevant information about the appearance of the chips, although it was acquired through somewhat underhanded means.

Despite this, they have only been able to approximate the appearance of each chip independently within a cube with a uniform distribution.

Unfortunately, estimating the expected number of chips obtained per point was an ICPC World Finals-level problem, so they failed to estimate it. Now, they have decided to solve an easier problem: given the side length of a cube, calculate its volume. Is this problem easy enough to solve? Help them find the volume of the cube.

Input

The first line contains a single integer ($$$1 \leq n \leq 20$$$) – the side length of the cube.

Output

Print a single integer – the volume of the given cube.

Example
Input
9
Output
729