alextoledoglez / circlearea

The formula to calculate the Area of a Circle is defined as: area = pi * radius2. For this problem we consider pi = 3.14159:

• Calculate the area using the formula given in the description of the problem.

Entry

The input consists of a floating point value (double precision), which is the variable radius.

Departure

Display the message "A =" followed by the area value, as in the following examples, with four places after the decimal point. Use double precision variables. As with all problems, don't forget to print a line break after the result, otherwise you will. you will receive a "Presentation Error" message.

Input / Output Examples

2.00

A = 12.5664

100.64

A = 31819.3103

150.00

A = 70685.7750