Description

Enter the radius of the bottom and the height of the cone, calculate the volume of the cone then output it.

Input Format

Enter the radius of the bottom and the height of the cone, calculate the volume of the cone then output it.

Output Format

One numbers of the volume of the cone(the result retains 1 decimal).

2 4

16.7

Limit and hint

For $100\%$ testcases， $r,h\leq10^3$.