I'm aware that the term 'C/C++' is disapproved of (sometimes quite vehemently) by some programmers, usually those who either consider themselves "pure" C or C++ programmers. A drawback to the term is that no two programmers appear to mean the same thing when they use it.
I use the term to mean: the code can compile either as C or C++. I have to work in both environments. Sometimes, if I rename my C program to .cpp, the compilers emit warnings I'd not have seen otherwise (and, on rare occasions, vice versa). While I am not ideological about programming languages, I am accustomed to and happy working in C.
It would be accurate to say that the source code on this site is in C, but I wanted to convey the point that C++ zealots need not therefore consider the code unusable. So despite the baggage behind "C/C++", I used that term.