Question

USE C++

Demonstrate how to write an interface for a VEHICLE class using C++. In your interface, demonstrate the following (use comments to explain or for demonstration):

-Interface implementation

-Multiple interface implementation for a single class

-Example of a Diamond Inheritance problem

-Polymorphism

Explain each term above clearly in the code example and discuss how it is being used

USE C++

Answer 1

/* Overall problem divided into to 3 section

First program is example of

1) Interface implementation

2) Polymorphism

1st program

*/

#include <iostream>

using namespace std;

// Base class
class Vehicle {
   public:
      // pure virtual function changeGear providing interface framework.
      virtual void changeGear(int g) = 0;
   
};

// Derived Bicycle classes that implement all pure virtual method of class vehicle
class Bicycle: public Vehicle {
    int gear;
   public:
   //override changeGear function
      void changeGear(int g) {
         gear=g;
         cout<<"\n Bicycle Now the Gear is: "<<gear;
      }
};

// Derived Car classes that implement all pure virtual method of class vehicle
class Car: public Vehicle {
    int gear;
   public:
   //override changeGear function
      void changeGear(int g) {
         gear=g;
         cout<<"\n Car Now the Gear is: "<<gear;
      }
};

int main(void) {
   Bicycle Rect;//creat object
Rect.changeGear(1) ;//call override method
Car car;
car.changeGear(3) ;

   return 0;
}

/*

output

Bicycle Now the Gear is: 1
Car Now the Gear is: 3

*/

/*

2nd Problem

Example of a Diamond Inheritance problem

The diamond problem occurs when two superclasses of a class have a common base class. For example, in the following diagram, the TA class gets two copies of all attributes of Person class, this causes ambiguities.

*/

#include <iostream>

using namespace std;

// Base class
class Vehicle {
   public:
      Vehicle(int n){
          // only because of diamond proble below function called twice
          cout<<"\n Model No:"<<n;
      }
   
};

// Derived Bicycle classes
class Bicycle: public Vehicle {
    int gear;
   public:

      Bicycle(int n):Vehicle(n){
        
      }
};

// Derived Car classes
class Car: public Vehicle {
    int gear;
   public:

      Car(int n):Vehicle(n){
        
      }
};

class Brand:public Car,public Bicycle{
    public:
    Brand(int n):Car(n),Bicycle(n){
      
    }
};

int main(void) {

Brand brand(100);

   return 0;
}

/*

output

Model No:100
Model No:100

*/

/*

problem 3

Multiple Inheritance in C++

Multiple Inheritance is a feature of C++ where a class can inherit from more than one classes.

here is program with vehicle. It generate conflict problem hence it is solved by specifying base class name before function call

*/

#include <iostream>

using namespace std;
class vehicle
{
public:
     void someFunction( )
     { cout<<"\n Vehicle Function "; }
};
class cycle
{
    public:
    void someFunction( )
     { cout<<"\n cycle Function ";}
};
class derived : public vehicle, public cycle
{
  
};

int main()
{
    derived obj;
    obj.vehicle::someFunction( ); //called function from vehicle class
    obj.cycle::someFunction();   // called function from cycle class
}

/*

output

Vehicle Function
cycle Function

*/