Area of a Circle OJ: URI Problem no: 1002

Area of a Circle

OJ: URI 

Problem no: 1002   

 

Formula of area of a circle is  A = pi * R^2 .

(here pi = 3.14159 and R is the radius  of circle taken from the user.)

Print the area with four places after the decimal point.
Output should be like: "A=#.0000"

(If you have any more question or confusion, just comment it below.)


 author : Amirul Islam