Time Limit: 1 sec
Radius of a Circle, R is given. What will be the Circumference of the Circle?
Note : The Circumference of a Circle is 2 * pi * radius [pi = 3.1416]
The input file contains a series of line. Each line contains a single integer Radius R (R <= 100). Input is terminated by EOF.
The output will show the Circumference of the Circle rounded to 2 decimal points in a separate line.
Problem Setter: Samia Safa Ahmed