HoMM3 HD is a mod (add-on) for the game Heroes of Might and Magic 3.

Does anyone have a link to C++? A free one?

I'm making an HD mod for Visual C++ 2008 Express.
Here's a link to 2010:
http://www.microsoft.com/express/Downloads/#2010-All
You choose the language, download the 1.8 GB DVD image.
Or you can click on Visual C++ 2010 Express, but the online installation isn't very convenient.

Then you download the 1.5 GB SP1 image link