Multiple Inheritance in C++.

Multiple Inheritance in C++

Multiple Inheritance: It is the process of deriving a new class that inherits the attributes from two or more classes.

#include<iostream.h>

#include<conio.h>

class A

{

  public:

  int x;

  void getx()

    {

      cout << "enter value of x: "; cin >> x;

    }

};

class B

{

  public:

  int y;

  void gety()

  {

      cout << "enter value of y: "; cin >> y;

  }

};

class C : public A, public B   //C is derived from class A and class B

{

  public:

  void sum()

  {

      cout << "Sum = " << x + y;

  }

};

int main()

{

  C obj1; //object of derived class C

  obj1.getx();

  obj1.gety();

  obj1.sum();

  return 0;

}   

Expected Output:-

enter value of x: 5

enter value of y: 4

Sum = 9

//Implementation of Multiple Inheritance.

#include<iostream.h>

#include<conio.h>

class Mammal {
  public:
    Mammal()
    {
      cout << "Mammals can give direct birth." << endl;
    }
};

class WingedAnimal {
  public:
    WingedAnimal()
    {
      cout << "Winged animal can flap." << endl;
    }
};

class Bat: public Mammal, public WingedAnimal {

};

int main()
{
    Bat b1;
    return 0;
}

Expected Output:-

Mammals can give direct birth.

Winged animal can flap.


//More Example.
#include <iostream.h>  
#include <conio.h> 
 class A  
{  
    protected:  
     int a;  
    public:  
    void get_a(int n)  
    {  
        a = n;  
    }  
};  
  
class B  
{  
    protected:  
    int b;  
    public:  
    void get_b(int n)  
    {  
        b = n;  
    }  
};  
class C : public A,public B  
{  
   public:  
    void display()  
    {  
        std::cout << "The value of a is : " <<a<< std::endl;  
        std::cout << "The value of b is : " <<b<< std::endl;  
        cout<<"Addition of a and b is : "<<a+b;  
    }  
};  
int main()  
{  
   C c;  
   c.get_a(10);  
   c.get_b(20);  
   c.display();  
  
    return 0;  
}  
Expected Output:-

The value of a is : 10
The value of b is : 20
Addition of a and b is : 30


//More Example..
#include<iostream.h>
#include<conio.h>
class A  
{  
    public:  
    void display()  
    {  
        std::cout << "Class A" << std::endl;  
    }  
};  
class B  
{  
    public:  
    void display()  
    {  
        std::cout << "Class B" << std::endl;  
    }  
};  
class C : public A, public B  
{  
    void view()  
    {  
        display();  
    }  
};  
int main()  
{  
    C c;  
    c.display();  
    return 0;  
}  
Output:

error: reference to 'display' is ambiguous

        display();

//More Example..
#include<iostream.h>
#include<conio.h>

class student
{
protected:
int rno,m1,m2;
public:
void get()
{
cout<<"Enter the Roll no :";
cin>>rno;
cout<<"Enter the two marks   :";
cin>>m1>>m2;
}
};
class sports
{
protected:
int sm;                   // sm = Sports mark
public:
void getsm()
{
cout<<"\nEnter the sports mark :";
cin>>sm;

}
};
class statement:public student,public sports
{
int tot,avg;
public:
void display()
{
tot=(m1+m2+sm);
avg=tot/3;
cout<<"\n\n\tRoll No    : "<<rno<<"\n\tTotal      : "<<tot;
cout<<"\n\tAverage    : "<<avg;
}
};
void main()
{
clrscr();
statement obj;
obj.get();
obj.getsm();
obj.display();
getch();
}