We've had this debate before, with the conclusion that it doesn't really matter. The compiler will catch all errors except for a special case with "using namespace std" where undefined behaviour is invoked if you forget to include a file under certain conditions.
"using namespace std" is perfectly legitimate (especially for the example programs often posted here).
But you must remember to never use any using-declaration within globals scope of header files, because that will affect every file that includes the header.
There are no degrees of following the standard. Either you do, or you don't. Every variant does.Originally Posted by Mr.OC