Question

Write a Perl program that computes the circumference of a circle. Your program prompts for and accepts a radius from the person running the program. So, if the user enters 12.5 for the radius, she should get the answer about 78.5. Circumference is 2π times the radius (approximately 2 times 3.141592654).

Answer 1

This is a simple Perl program to calculate the circumference of a circle by prompting the user for the radius of the circle.

Comments are added to explain every step

#Prompt the user for radius of circle by printing a statement to STDOUT
print"Enter radius of circle: ";
#Make a variable $radius and read the value from STDIN
my $radius=<STDIN>;
#Remove the extra line read from input
chomp $radius;
#print the radius read from STDIN
print"$radius ";
#Make a variable $circumference which is equal to 2*pi*$radius
my $circumference=3.141592654*2*$radius;
#Print the circumference of circle to STDOUT
print"Circumference of circle: $circumference";

Sample output for radius 12.5 which comes out to be nearly equal to 78.5