I don't know about notepad 5, the error you mention i'ts because you didn't
specified an input file, maybe you missed to add the source files to the command
line, i suggest to you read the notepad 5 help file, otherwise try using some
ide like Dev-CPP or wxDev-CPP.

The reserved words are text identifiers for special use by the compiler, the
C/C++ reserved words (most of them standarized) these words can't be used as
variable, constant or identifier name, for example: "for" is a reserved word
because it means a loop block start, the "if" word can't be used as a variable
name because it means a conditional block beginning, you can get a lista of them
in: http://www.cppreference.com/wiki/keywords/start