Sphere Volume

Version: Phuoc Hung OJ Extended

Problem Statement

Given the radius $r$ of a sphere, compute its volume $V=\dfrac43\pi r^3$ using Python 3 math.pi. Print exactly 6 decimal places.

Input

The only line contains real sphere radius $r$.

Output

Print the sphere volume with exactly 6 decimal places.

Subtasks

• Subtask 1 (100 points): $r\ge0$.

Examples

Example 1

Input

1

Output

4.188790

Explanation. Substituting 1 into (4 / 3) × π × r³ gives approximately 4.18879020479. The required output formatting produces 4.188790.

Example 2

Input

2

Output

33.510322

Explanation. Substituting 2 into (4 / 3) × π × r³ gives approximately 33.5103216383. The required output formatting produces 33.510322.

Example 3

Input

0.5

Output

0.523599

Explanation. Substituting 0.5 into (4 / 3) × π × r³ gives approximately 0.523598775598. The required output formatting produces 0.523599.