This article is probably one of the reasons why C++ gets the reputation it has. Please do not program like this. Aside from the fact that this is C++98, which lacks tons of features now widely accepted and useful in C++, the code in this article has no consistency, uses most bad practices I know, and is most certainly not geared towards competitive programming.
All this information is readily found in any online docs about C++. Please read those.
On that note, these links are the best place to start when it comes to writing "good" C++ these days:
https://isocpp.org/blog/2015/09/stroustrup-cppcon15-keynote