High quality c ++

1. Try to use const instead of macro definition because there is no type check for macro definition.
2. for complex object types, you are advised to use const &'s type transfer parameters to avoid calling constructor and destructor and improve the efficiency.
3. Features of member functions being overloaded:
(1) the same range (in the same class );
(2) The function name is the same;
(3) parameters are different;
(4) virtual keywords are optional.
4. Overwrite ※hide
(1) different function scopes are not derived classes and basic classes.
(2) functions with the same name and different parameters, or functions with the same name and parameters are hidden if there is no virtual in the base class, and the base class has virtual as overwrite.
5. The default value of the parameter can only appear in the declaration of the function, but not in the definition body.
6. If the function has multiple parameters, the parameter can only be left one by one from the back to the front.
7. inline is a kind of "keyword used for implementation", rather than a kind of "keyword used for declaration". The member functions in the class declaration will automatically become inline functions.