_MSC_VER

[JasBeckC]

Hello everyone,

I'm a beginner in C++. Could you please help me understand what _MSC_VER is?

what does these lines of code mean? (Even reading the comment doesn't give me a clue)

  // The basic math functions should be in namespace std but aren't in VCPP6
   #if !defined(_MSC_VER)
   using namespace std;
   #endif 

Thank you !!!

[MiiNiPaa]

There are some defines which compilers do to help determine which platform you are compiling on, with which compiler, etc.
http://sourceforge.net/p/predef/wiki/Compilers/#microsoft-visual-c

This part of code should check if code is compiling under Visual Studio and only adds line 3 to the source if you are not.