On August 9th, I posted the following problem on community.csdn.net, under VC/MFC 基础类:

Problem: Write code to generate a bitmap rotated 90 degrees clockwise from the original bitmap, without using any graphics library.

If you want to post your code here, write on your own, do not refer to anything else, no copy/paste, write your code here, review your code before submitting, and include how much time you spend. Add comments in English when possible.

I want to see who can give a good enough answer.

There have been lots of responses to this simple programming problem and some quite interesting discussions. Here is the link to the CSDN thread: http://community.csdn.net/Expert/topic/3254/3254627.xml?temp=.7896845

Here is the link to my comments, including my code: http://blog.joycode.com/fyuan/articles/30945.aspx