！ Understanding of C + + classes

C + + classes can be divided into two classes, one is the class of the entity (i.e., the entity Class), and one is the function class (i.e., function Class).

For the class that constructs the entity, including the attribute of this entity already has its own function;

The function class consists of the functions that deal with the entity and some parameters, but these functions are not possessed by the entity itself. This kind of constructor is usually used to pass in parameters, i.e, entities. If the entity has a large amount of data, usually this parameter uses pointers, so you can save memory by getting data in one place.

One way to do this when declaring a class is if the entity class is not normally required.

In the case of a functional class, because the entity is processed, and the entity has a large amount of data, you can use pointers instead of pointers, but in places where the constructors pass in parameters.

！ Understanding of C + + classes