In this example we see the files
   student.h	where is given the definition of the Student
		structure and some of its operators
   student.cpp  where is the implementation of the operators
		of the Student structure
   main.cpp	the main program, where we use the Student structure.
We can compile the program with
   % g++ main.cpp student.cpp
which results in the executable a.out.
Or we can compile with
   % g++ -o main main.cpp student.cpp
which results in the executable main.