public/subjects/getarea/README.md

get-area

instructions

• Write a program that takes a number and prints the area of the circle.
  • The area of the circle is π times the radius squared.
  • if the number is not positive or is not a number, print Error followed by ('\n')
  • if the number is positive, print the area of the circle followed by ('\n')
  • if the number of arguments is not 1 print ('\n')
  • You may assume that the value of π is 3.14

Usage

$ go run . | cat -e
$
$ go run . 10 | cat -e
315$
$ go run . 4 | cat -e
50$
$ go run . -10 | cat -e
Error$
$ go run . "Hello World!" | cat -e
Error$