g++ command line options

• -o : name the output file.
• -Wall : all warnings.
• -pedantic : follow strict ISO C++ rules.
• -Weffc++ : follow Scott Myer's Effective C++ solutions.

More to come as a I experiment with them.

'NULL' was not declared in scope

(and cout, for that matter).

• For NULL: use #include or
• For cout: use the scope operator: std::cout or put 'using std::cout' at the top of the file.