Inheritance

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                     Inheritance

Inheritance

  • The ability of one class, called child class, to acquire properties from another class, called as parent class is called as inheritance.
  • The parent class is also called as base class and child class is also called as derived class.
  • Inheritance is used to achieve reusability of code, which is an important concept of object oriented programming.


Example of single inheritance
class a //base class or parent class
{
public:
void fun()
{
cout<<“fun”;
}
};
class b:public a //child class or derived class
{;}
void main()
{
b ob;
  ob.fun(); /*fun of class a called with derived class b’s  object, as fun is inherited in b class*/
}
Output: fun

Protected class member

  • When a class member is declared to be protected, then the protected class member can be accessed within the class and in the immediately derived class also.
  • The visibility of class member as protected is more than private and less than public.

Example of protected class member

class a
{
protected:
int x; /*protected class member x can be accessed in derived class b*/
};
class b : public a
{
public:
void fun()
{
x=10; /*protected class member x accessed in derived
class b*/
cout<<x;
}
};
void main()
{
b ob; 
ob.fun();
}

Output: 10

The use of many visibility operators we can easily define it.


Way of inheritance → 
Base class members ↓
private
protected
public
private
can never be inherited in derived class
can never be inherited in derived class
can never be inherited in derived class
protected
becomes private in derived class, after inheritance
remains protected in derived class, after inheritance
remains protected in derived class, after inheritance
public
becomes private in derived class, after inheritance
remains protected in derived class, after inheritance
remains public in derived class, after inheritance




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