Inheritance

class Sub_Class : public Super_Class
{

}

From based(super, parent) class to derived(sub, child) class

Polymorphic or Liskov Substitution Principle

class A;

class B : public A;

int main()
{
A objA;
B objB;

A* q = &objB
}

A parent’s pointer can point to it’s child, but it cannot access the member that only in B

UPerson is the parent, student is the child

Perfect match of function argument will be more prefered

• But when when we are calling using reference, we will use the type of the reference

class person;

class student: public person;

class PG: public student;

int main()
{
A objA;
B objB;

A* q = &objB
}

PG is the indirect derived class of person

person is the indirect base class

Initialization in an Inheritance Hierarchy

Derived class should use MIL to initialize the base class

C++ will add the default constructor of base class to MIL

If there are no default constructor, compile error

Problems of Inheritance

Slicing:

If we copy a derived class to base, the object will be sliced