from math import pi
import pprint
'''
r = radius
circle_area = pi * r**2
circle_circumference = 2 * pi * r
h = height
cylinder_volume = pi * r**2 * h
cylinder_surface = 2 * (pi * r**2) + (2 * pi * r * h)
constraint for cylinder_volume be a constant of 1 liter (cubic centimeter)
cylinder_volume = 1000
h in terms of r
h = 1000/(pi * r**2)
substitute in
cylinder_surface = 2 * (pi * r**2) + (2 * pi * r * 1000/(pi * r**2))
'''
mylist = [] # create a list of (surface area, radius)
for r in range(1, 21): # assume a maximum of 20cm radius
cylinder_surface = 2 * (pi * r**2) + (2 * pi * r * 1000/(pi * r**2))
mylist.append((cylinder_surface, r))
# test
pprint.pprint(mylist)