How to code a circular stair?

[Killmo]

Hi there,

i'm an absolute beginner, so i registered to improve my skills.

Some facts about me: I study media informatics. Currently i'm learning for a test regarding basics in media (especially graphics and sound). A small part of this is OpenGL.
So i started creating polygons, changing colors, changing the size by keyboard or just let the polygon spin around by pressing x, y or z to rotate to these directions. And it's really fun!!!

Now to my question:
A fellow student told me about the test she wrote a few months ago in this discipline. The question regarding OpenGL was the following:
Model a circular stair, the steps can be entered dynamically. There must be colors and it is all 3D. Each step must be shifted by 20°. The camera view was given.
(Hope you know what i mean, my technical english is not very good ).
That's what she has told me, i don't have more information.

The OpenGL-parts in my book just approach things like the structure of an OpenGL-programm, the colors, the primitives - that's all. It's just the basics. So i guess this question should be solved very easily.
But i don't have a clue how to make it. I even checked my red book (without it i would be lost, because my book from the university really sucks) and google. But without success.

Well, i'm pretty sure i won't get the same question. But i'd really like to know how this works.

Maybe there's a nice person here to help me with that?

[edit]I forgot an important information: The test is just written on paper - no PC is used. [/edit]

[tanzanite]

This is not really a OpenGL question (you seek to programmatically create a stair mesh/model suitable for drawing in 3D):
* for generating the mesh data etc - a more appropriate forum would be for example http://www.gamedev.net/forum/21-general-programming/
* for drawing - it would be prudent to learn using buffer objects and not to use any of the deprecated immediate mode stuff.