Inheritance in C++

hybrid-inheritance,cpp

#include<iostream>
using namespace std;
class A //base class
{
  public:
  int i;
    void data1(int j)
    {
        i=j;
        cout<<"The result is: \t"<<i<<endl;
    }
    void display()
    {
        cout<<i;
    }
};
class B:virtual public A //derived class
{
  int x;
  public:
  void data2(int y)
  {
    x=y;
    cout<<"The result is: \t"<<x<<endl;
  }
  void data3(int z, int x)
  {
      i=x;
      data1(z);
  }
};
class C:virtual public A
{
    int k;
public:
    void data4(int c)
    {
        k=c;
        cout<<"The value of k is :\t"<<k<<endl;
    }
};
class D:public B,public C
{
    int y;
public:
    void data5(int p)
    {
        y=p;
        cout<<"The value of p is :\t"<<y<<endl;
    }
};
int main()
{
  D obj;
  obj.i=100;
  obj.display();
  return 0;
}
// A can be accessed via both directions therefore we have to write virtual before inheriting ...

inherit-normal.cpp

//Using Public
#include<iostream>
using namespace std;
class A //base class
{
  int i;
  public:
    void data1(int j)
    {
        i=j;
        cout<<"The result is: \t"<<i<<endl;
    }
};
class B:public A //derived class
{
  int x;
  public:
  void data2(int y)
  {
    x=y;
    cout<<"The result is: \t"<<x<<endl;
  }
};
int main()
{
  //A obj1;
  //obj1.data1(30);
  B obj2;
  obj2.data2(50);
  obj2.data1(30);
  return 0;
}

inherit-special.cpp

//Using protected
#include<iostream>
using namespace std;
class A //base class
{
    protected:
  int i;
  public:

    void data1(int j)
    {
        i=j;
        cout<<"The result is: \t"<<i<<endl;
    }
};
class B:private A //derived class
{
  int x;
  public:
  void data2(int y)
  {
    x=y;
    cout<<"The result is: \t"<<x<<endl;
  }
  void data3(int z, int x)
  {
      i=x;
      data1(z);
  }
};
int main()
{
  B obj2;
  obj2.data2(50);
  obj2.data3(100,90);
  //obj2.i=100;
  return 0;
}

no-inherit.cpp

//Normal without inheritance
#include<iostream>
using namespace std;
class A
{
  int i;
  public:
  void data1(int j)
  {
    i=j;
    cout<<"The result is: "<<i<<endl;
  }
};
class B
{
  int x;
  public:
  void data2(int y)
  {
    x=y;
    cout<<"The result is: "<<x<<endl;
  }
};
int main()
{
  A obj1;
  obj1.data1(30);
  B obj2;
  obj2.data2(50);
 }