URI 1002:: SOLUTION

                                                                                                     URI Online Judge | 1002

Area of a Circle

The formula to calculate the area of a circumference is defined as A = π . R2. Considering to this problem that π = 3.14159:

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

Input

The input contains a value of floating point (double precision), that is the variable R.

Output

Present the message "A=" followed by the value of the variable, as in the example bellow, with four places after the decimal point. Use all double precision variables. Like all the problems, don't forget to print the end of line after the result, otherwise you will receive "Presentation Error".

Input Samples	Output Samples
2.00	A=12.5664

100.64

A=31819.3103

150.00

A=70685.7750

[WAIT]

     First of all, think yourself that you have tried enough for the problem. If you did not please read the program once. REMEMBER one think, just believe in yourself.....YOU CAN.....YOU KNOW....

                                                     

See the ANSWER here...