A program must calculate the circumference of a circle. The user enters the radius of the circle.
A radius of zero or less is invalid.
The formula to calculate the circumference of a circle is:
circumference = 2πr
π is the constant Pi
r is the radius.
Amend the code to add or complete lines to:
import the math library
create two variables
take input from the user
check for an invalid input of zero or less
display a message to tell the user the input is invalid
calculate the circumference
round the circumference to three decimal places using the round() function.
Do not add any additional functionality.