The document provides an extensive overview of inheritance concepts in C++, illustrating various types such as public, protected, private, single, multiple, multilevel, hierarchical, and hybrid inheritance through practical coding examples. Each type of inheritance is demonstrated with simple classes showcasing access levels for class members within the derived classes and the interaction between them. The examples illustrate how different inheritance structures affect member accessibility and provide comprehensive outputs to visualize the concepts.

1. For example, Classes B, C and D all contain the variables x, y and z
class A
{
public:
int x;
protected:
int y;
private:
int z;
};
class B : public A
{
// x is public
// y is protected
// z is not accessible from B
};
class C : protected A
{
// x is protected
// y is protected
// z is not accessible from C
};
class D : private A
// 'private' is default for classes
{
// x is private
// y is private
// z is not accessible from D
};

2. Example 1: C++ public Inheritance
#include <iostream>
using namespace std;
class Base
{ private: int pvt = 1;
protected: int prot = 2;
public: int pub = 3;
// function to access private member
int getPVT()
{ return pvt; }};
class PublicDerived : public Base
{ public:
// function to access protected member from Base
int getProt()
{ return prot;
}
};
int main()
{
PublicDerived object1;
cout << "Private = " << object1.getPVT() <<
endl;
cout << "Protected = " << object1.getProt() <<
endl;
cout << "Public = " << object1.pub << endl;
return 0;
}
Output
Private = 1
Protected = 2
Public = 3

3. // C++ program to demonstrate the working of protected inheritance
#include<iostream>
using namespace std;
class Base
{ private: int pvt = 1;
protected: int prot = 2;
public: int pub = 3;
// function to access private member
int getPVT() { return pvt; } };
class ProtectedDerived : protected Base
{ public:
// function to access protected member from
Base
int getProt()
{ return prot; }
// function to access public member from Base
int getPub()
{ return pub;
}};
int main()
{
ProtectedDerived object1;
cout << "Private cannot be accessed." <<
endl;
cout << "Protected = " <<
object1.getProt() << endl;
cout << "Public = " << object1.getPub() <<
endl;
return 0;
}
Output
Private cannot be accessed.
Protected = 2
Public = 3

4. // C++ program to demonstrate the working of private inheritance
#include <iostream>
using namespace std;
class Base
{ private: int pvt = 1;
protected: int prot = 2;
public: int pub = 3;
// function to access private member
int getPVT()
{ return pvt; }};
class PrivateDerived : private Base
{ public:
// function to access protected member from Base
int getProt() { return prot; }
// function to access private member
int getPub()
{ return pub; }};
int main()
{
PrivateDerived object1;
cout << "cannot be accessed." << endl;
cout << "Protected = " <<
object1.getProt() << endl;
cout << "Public = " << object1.getPub()
<< endl;
return 0;}
Output
Private cannot be accessed.
Protected = 2
Public = 3

5. Single inheritance Example 1
#include <iostream>
// Base class
class Shape
{ public:
void setWidth(int w)
{ width = w; }
void setHeight(int h)
{ height = h; }
protected: int width; int height;
};
// Derived class
class Rectangle: public Shape
{ public:
int getArea()
{ return (width * height); }
};
int main(void)
{
Rectangle Rect;
Rect.setWidth(5);
Rect.setHeight(7);
// Print the area of the object.
cout << "Total area: " << Rect.getArea() <<
endl;
return 0;
}
When the above code is compiled and
executed, it produces the following result −
Total area: 35

6. Example 2
# include <iostream.h>
class Value
{
protected:
int val;
public:
void set_values (int a)
{ val=a;}
};
class Cube: public Value
{
public:
int cube()
{ return (val*val*val); }
};
int main ()
{
Cube cub;
cub.set_values (5);
cout << "The Cube of 5 is::" << cub.cube() << endl;
return 0;
}
Result:
The Cube of 5 is:: 125
In the above example the derived class "Cube" has only one base
class "Value". This is the single inheritance OOP's concept.

7. C++ program for Single inheritance
#include <iostream>
using namespace std;
// base class
class Vehicle {
public:
Vehicle()
{
cout << "This is a Vehicle" << endl;
}
};
// sub class derived from two base classes
class Car: public Vehicle
{
-------
};
// main function
int main()
{
/* creating object of sub class
will invoke the constructor of
base classes */
Car obj;
return 0;
}
Output:
This is a vehicle

8. program to explain multiple inheritance
#include <iostream.h>
// first base class
class Vehicle {
public:
Vehicle()
{ cout << "This is a Vehicle" << endl; }
};
// second base class
class FourWheeler {
public:
FourWheeler()
{
cout << "This is a 4 wheeler Vehicle" <<
endl;
} };
// sub class derived from two base classes
class Car: public Vehicle, public
FourWheeler {
};
int main()
{
/* creating object of sub class will invoke
the constructor of base classes */
Car obj;
return 0;
}
Output:
This is a Vehicle
This is a 4 wheeler Vehicle

9. program to explain multiple inheritance
#include <iostream>
using namespace std;
// Base class Shape
class Shape
{ public:
void setWidth(int w)
{ width = w; }
void setHeight(int h)
{ height = h; }
protected: int width; int height; };
// Base class PaintCost
class PaintCost
{ public:
int getCost(int area)
{ return area * 70; } };
// Derived class
class Rectangle: public Shape, public PaintCost
{ public: int getArea()
{ return (width * height);
}
};
int main(void)
{ Rectangle Rect;
int area;
Rect.setWidth(5);
Rect.setHeight(7);
area = Rect.getArea();
// Print the area of the object.
cout << "Total area: " << Rect.getArea() << endl;
// Print the total cost of painting
cout << "Total paint cost: $" << Rect.getCost(area) << endl;
return 0; }
When the above code is compiled and executed, it produces the
following result −
Total area: 35
Total paint cost: $2450

10. Example:
#include <iostream.h>
using namespace std;
class Square
{
protected:
int l;
public:
void set_values (int x)
{ l=x;}
};
class CShow
{
public:
void show(int i);
};
void CShow::show (int i)
{
cout << "The area of the square is::" << i << endl;
}
class Area: public Square, public CShow
{
public:
int area()
{ return (l *l); }
};
int main ()
{
Area r;
r.set_values (5);
r.show(r.area());
return 0;
}
Result:
The area of the square is:: 25

11. program to explain multlevel inheritance
#include <iostream.h>
// base class
class Vehicle
{
public:
Vehicle()
{ cout << "This is a Vehicle" << endl; }
};
// sub class derived from vehicle base class
class fourWheeler: public Vehicle
{ public:
fourWheeler()
{
cout<<"Objects with 4 wheels are
vehicles"<<endl;
} };
// sub class derived from two base classes
class Car: public fourWheeler{
public:
car()
{ cout<<"Car has 4 Wheels"<<endl; }
};
int main()
{
//creating object of sub class will invoke
the constructor of base classes
Car obj;
return 0;
}
output:
This is a Vehicle
Objects with 4 wheels are vehicles
Car has 4 Wheels

17. #include <iostream.h>
class mm
{
protected:
int rollno;
public:
void get_num(int a)
{ rollno = a; }
void put_num()
{ cout << "Roll Number Is:n"<< rollno << "n"; }
};
class marks : public mm
{
protected:
int sub1;
int sub2;
public:
void get_marks(int x,int y)
{ sub1 = x;
sub2 = y; }

18. void put_marks(void)
{ cout << "Subject 1:" << sub1 << "n";
cout << "Subject 2:" << sub2 << "n"; }
};
class res : public marks
{
protected:
float tot;
public:
void disp(void)
{
tot = sub1+sub2;
put_num();
put_marks();
cout << "Total:"<< tot; }
};
int main()
{
res std1;
std1.get_num(5);
std1.get_marks(10,20);
std1.disp();
return 0;
}
Result:
Roll Number Is: 5
Subject 1: 10
Subject 2: 20
Total: 30
In the above example, the derived function "res" uses the function
"put_num()" from another derived class "marks", which just a level above.
This is the multilevel inheritance OOP's concept in C++.

22. Hierarchical Inheritance
In this type of inheritance, more than one sub
class is inherited from a single base class. i.e.
more than one derived class is created from a
single base class.

23. // C++ program to implement Hierarchical Inheritance
#include <iostream>
using namespace std;
// base class
class Vehicle
{
public:
Vehicle()
{
cout << "This is a Vehicle" << endl;
}
};
// first sub class
class Car: public Vehicle
{
----------
};
// second sub class
class Bus: public Vehicle
{
};
int main()
{
// creating object of sub class will
invoke the constructor of base class
Car obj1;
Bus obj2;
return 0;
}
Output:
This is a Vehicle
This is a Vehicle

24. #include <iostream.h>
class Side
{
protected:
int l;
public:
void set_values (int x)
{ l=x;}
};
class Square: public Side
{
public:
int sq()
{ return (l *l); }
};
class Cube: public Side
{
public: int cub()
{ return (l*l*l); }
};
Example:
int main ()
{
Square s;
s.set_values (10);
cout << "The square value is::"
<< s.sq() << endl;
Cube c;
c.set_values (20);
cout << "The cube value is::"
<< c.cub() << endl; return 0; }
Result:
The square value is:: 100
The cube value is::8000

25. Get square and cube of a number by using Hierarchical Inheritance
Class Number
{ private: int num;
public: void getNumber(void)
{ cout << "Enter integer number: "; cin >>
num; }
int returnNumber(void)
{ return num; } };
class Square:public Number
{ public: int getSquare(void)
{ int num,sqr; num=returnNumber();
sqr=num*num; return sqr; } };
class Cube:public Number { private:
public: int getCube(void) { int
num,cube; num=returnNumber();
cube=num*num*num;
return cube; } };
int main()
{
Square objS; Cube objC;
int sqr,cube; objS.getNumber();
sqr =objS.getSquare();
cout << "Square of "<<
objS.returnNumber() << " is: " << sqr <<
endl; objC.getNumber();
cube=objC.getCube();
cout << "Cube of "<< objS.returnNumber()
<< " is: " << cube << endl;
return 0; }
Output
Enter an integer number: 10 Square of 10
is: 100
Enter an integer number: 20
Cube of 10 is: 8000

26. // C++ program to implement Hierarchical Inheritance
#include <iostream.h>
#include <string.h>
class member
{ char gender[10]; int age;
public: void get() { cout << "Age: ";
cin >> age; cout << "Gender: ";
cin >> gender; }
void disp()
{ cout << "Age: " << age << endl;
cout << "Gender: " << gender ; cout<< endl;
} };
class stud : public member
{ char level[20];
public: void getdata()
{ member::get();
cout << "Class: "; cin >> level; }
void disp2()
{ member::disp();
cout << "Level: " << level << endl; } };
class staff : public member
{ float salary;
public: void getdata()
{ member::get();
cout << "Salary: Rs."; cin >> salary; }
void disp3()
{ member::disp();
cout << "Salary: Rs." << salary << endl; }};
int main()
{ member M;
staff S; stud s;
cout << "Student" << endl; cout << "Enter data" << endl;
s.getdata();
cout << endl << "Displaying data" << endl;
s.disp();
cout << endl << "Staff Data" << endl;
cout << "Enter data" << endl;
S.getdata();
cout << endl << "Displaying data" << endl;
S.disp();
}

27. Output

28. // C++ program to implement Hybrid Inheritance
#include <iostream.h>
// base class
class Vehicle
{
public:
Vehicle()
{ cout << "This is a Vehicle" << endl;}
};
//base class
class Fare
{ public:
Fare()
{ cout<<"Fare of Vehiclen"; }
};
// first sub class
class Car: public Vehicle
{
};
// second sub class
class Bus: public Vehicle, public Fare
{
};
int main()
{
Bus obj2;
return 0;
}
Output:
This is a Vehicle
Fare of Vehicle

29. EXAMPLE
#include <iostream.h>
class mm
{
protected:
int rollno;
public:
void get_num(int a)
{ rollno = a; }
void put_num()
{ cout << "Roll Number Is:"<< rollno << "n"; }
};
class marks : public mm
{
protected:
int sub1;
int sub2;
public:
void get_marks(int x,int y)
{ sub1 = x;
sub2 = y; }
void put_marks(void)
{
cout << "Subject 1:" << sub1 << "n";
cout << "Subject 2:" << sub2 << "n";
}
};

30. class extra
{
protected:
float e;
public:
void get_extra(float s)
{e=s;}
void put_extra(void)
{ cout << "Extra Score::" << e << "n";}
};
class res : public marks, public extra{
protected:
float tot;
public:
void disp(void)
{ tot = sub1+sub2+e;
put_num();
put_marks();
put_extra();
cout << "Total:"<< tot; }
};
int main()
{
res std1;
std1.get_num(10);
std1.get_marks(10,20);
std1.get_extra(33.12);
std1.disp();
return 0;
}
Result:
Roll Number Is: 10
Subject 1: 10
Subject 2: 20
Extra score:33.12
Total: 63.12

31. • In the above example the derived class "res" uses the
function "put_num()". Here the "put_num()" function is
derived first to class "marks". Then it is derived and used
in class "res". This is an example of "multilevel
inheritance-OOP's concept". But the class "extra" is
inherited a single time in the class "res", an example for
"Single Inheritance". Since this code uses both
"multilevel" and "single" inheritance it is an example of
"Hybrid Inheritance".

32. Example

33. #include<iostream.h>
class Person
{ int id; char name[200];
public: void accept_person_details()
{ cout<<"n -------------------------------------------------- n";
cout<<"n Enter Id : “ ; cin>>id;
cout<<"n Enter Name : "; cin>>name;
}
void display_person_details()
{ cout<<"n -------------------------------------------------- n";
cout<<"n Id : "<<id;
cout<<"n Name : "<<name;
} };
class Teaching : public Person
{ char subject_name[100]; teacher_name[200];
public:
void accept_teacher_details()
{ accept_person_details();
cout<<"n Enter Subject Name : "; cin>>subject_name;
cout<<"n Enter Teacher Name : "; cin>>teacher_name;
}

34. void display_teacher_details()
{
display_person_details();
cout<<"n Subject Name : "<<subject_name;
cout<<"n Teacher Name : "<<teacher_name;
} };
class NonTeaching : public Person
{ char dept_name[200];
public:
void accept_nonteaching_details()
{ cout<<"n Enter Department Name : "; cin>>dept_name; }
void display_nonteaching_details()
{ cout<<"n Department Name : "<<dept_name; } };
class Instructor : public NonTeaching, public Teaching
{
public:
void accept_instructor_details()
{ accept_teacher_details(); accept_nonteaching_details(); }
void display_instructor_details()
{ display_teacher_details(); display_nonteaching_details(); } };

35. int main()
{
Instructor *inst;
int cnt, i;
cout<<"n Enter No. of Instructor Details You Want? : ";
cin>>cnt;
inst=new Instructor[cnt];
for(i=0; i<cnt; i++)
{ inst[i].accept_instructor_details(); }
for(i=0; i<cnt; i++)
{ inst[i].display_instructor_details(); }
return 0; }

36. Query

37. #include<iostream>
using namespace std;
class student //base class derivation
{ protected: int r_no;
public: void getRollno()
{ cout << "Enter the roll number of student : "; cin >> r_no; }
void putRollno() { cout << "nRoll Number -: " << r_no << "n"; } };
class test : public student //intermediate base class
{ protected: int part1, part2;
public: void getMarks() { cout << "Enter the marks of student in SA 1 : ";
cin >> part1; cout << "Enter the marks of student in SA 2 : ";
cin >> part2; }
void putMarks()
{ cout << "Marks Obtained : " << "n"; cout << " Part 1 -: " << part1;
cout << "n Part 2 -: " << part2 << "n"; } };

38. class sports
{ protected: int score;
public: void getSportsMarks()
{ cout << "Enter the marks in Physical Eduction : ";
cin >> score; }
void putSportsMarks()
{ cout << "Additional Marks : " << score << "n n"; } };
class result : public test, public sports //derived from test and sports
{ int total; public: void display () { total = part1 + part2 + score;
putRollno(); putMarks();
putSportsMarks(); cout << "Total Score : " << total ; } };
int main ()
{ result s1; s1.getRollno();
s1.getMarks(); s1.getSportsMarks();
s1.display();
return 0; }