Description

A sphere is a common model, and we all know its volume formula:
For a sphere with radius $r$, the volume is calculated as $V=\dfrac{4}{3}×π×r^3$, where $π=3.14$.
Given $r$, find $V$.

Input Format

Input a non-negative real number not exceeding $100$, representing the radius of the sphere.

Output Format

Output a real number representing the volume of the sphere, rounded to $2$ decimal places.

Sample

4

267.95