I have a C++ Code Fight question.

The return type of countPairsWithDiffrence() is one long rather than multiple.

where r, m, c, and countPairsWithDiffrence are identifiers using the type long.

You can think of it as a phrase of blindness such as inta, b, c;.

I don't know exactly because you uploaded it as a picture, but it's presumed to be '\t'. In ASCII code, '\t' is an integer 9 so long c['\t'] is equivalent to long c[9]. This means a declaration of a long array of size 9.

It's possible to code in this way, but if you write the code in that way, it's less readable, so don't copy it.