public/subjects/getarea

get-area

Instructions

Write a program that takes a positive number as radius and prints the area of a circle.

• The area of the circle is 3.14 times the radius squared.
• Only positive numbers will be accepted, otherwise print Error followed by ('\n')
• If the number of arguments is not 1 print ('\n')
• The output must be an integer.

Usage

$ go run . | cat -e
$
$ go run . 10 | cat -e
314$
$ go run . 4 | cat -e
50$
$ go run . -10 | cat -e
Error$
$ go run . "Hello World!" | cat -e
Error$