Cylinder Volume

Version: Phuoc Hung OJ Extended

Problem Statement

A right circular cylinder has base radius $r$ and height $h$. Its volume is $V=\pi r^2h$. Use Python 3 math.pi and print exactly 4 decimal places.

Input

The only line contains real base radius $r$ and height $h$ of the cylinder.

Output

Print cylinder volume $V$ with exactly 4 decimal places.

Subtasks

• Subtask 1 (100 points): $r,h\ge0$.

Examples

Example 1

Input

1 2

Output

6.2832

Explanation. Substituting 1, 2 into π × r² × h gives approximately 6.28318530718. The required output formatting produces 6.2832.

Example 2

Input

2.5 4

Output

78.5398

Explanation. Substituting 2.5, 4 into π × r² × h gives approximately 78.5398163397. The required output formatting produces 78.5398.

Example 3

Input

0 10

Output

0.0000

Explanation. Substituting 0, 10 into π × r² × h gives approximately 0. The required output formatting produces 0.0000.