Simple program using inheritance C++

A simple program demonstrating inheritance

#include 

#include

using namespace std;

class base 

{

  int i, j;

public:

  void set(int a, int b) 

{

 i = a; j = b; 

}

  void show() 

 {

  cout << i << " " << j << "\n"; 

  }

};

class derived : public base 

{

  int k;

public:

  derived(int x) 

  {

   k = x; 

   }

  void showk() 

 { 

  cout << k << "\n"; 

  }

};

int main()

{

  derived ob(3);

  ob.set(1, 2); 

  ob.show();    

  ob.showk();   

  return 0;

}

Using protected members

#include 

#include

using namespace std;

class base 

{

protected:

  int i, j; 

public:

void set(int a, int b) 

{

 i = a; j = b; 

 }

 void show() 

{ 

 cout << i << " " << j << "\n"; 

 }

};

class derived : public base 

{

  int k;

public:

          void setk() 

          {

           k = i*j;

           }

 void showk() 

{ 

cout << k << "\n"; 

 }

};

int main()

{

  derived ob;

  ob.set(2, 3); 

  ob.show();    

  ob.setk();

  ob.showk();

  return 0;

}

Protected inheritance

#include 

#include

using namespace std;

class base 

{

  int i;

protected:

  int j;

public:

  int k;

  void seti(int a) 

  {

   i = a; 

   }

  int geti() 

 { 

   return i; 

 }

};

class derived : protected base 

{

public:

  void setj(int a) 

  {

   j = a; 

}

  void setk(int a) 

  {

   k = a; 

   }

   int getj() 

  { 

   return j; 

   }

  int getk() 

  { 

   return k; 

   }

};

int main()

{

  derived ob;

  ob.seti(10);

  cout << ob.geti(); 

  ob.k = 10; 

  ob.setk(10);

  cout << ob.getk() << ' ';

  ob.setj(12);

  cout << ob.getj() << ' ';

  return 0;

}

Multiple inheritance 

#include 

#include

using namespace std;

class base1 

{

protected:

  int x;

public:

  void showx() 

{

 cout << x << "\n"; 

}

};

class base2 

{

protected:

  int y;

public:

void showy() 

{

 cout << y << "\n"; 

 }

};

class derived: public base1, public base2 

{

public:

  void set(int i, int j) 

{ 

x = i; y = j; 

}

};

int main()

{

  derived ob;

  ob.set(10, 20); 

  ob.showx();     

  ob.showy();     

  return 0;

}

Calling base class's constructor in derived class

#include 

#include

using namespace std;

class base1 

{

protected:

  int i;

public:

  base1(int x) 

   {

    i = x;

    cout << "Constructing base1\n";

    }

  ~base1() 

   { 

    cout << "Destructing base2\n"; 

    }

};

class base2 

{

protected:

  int k;

public:

  base2(int x) 

 { 

  k = x; 

  cout << "Constructing base2\n"; 

   }

  ~base2() 

   {

    cout << "Destructing base2\n"; 

    }

};

class derived: public base1, public base2 

{

  int j;

public:

  derived(int x, int y, int z): base1(y), base2(z)

    { 

      j = x; 

       cout << "Constructing derived\n"; 

     }

  ~derived() 

    { 

      cout << "Destructing derived\n"; 

     }

  void show() 

  {

    cout << i << " " << j << " " << k << "\n"; 

  }

};

int main()

{

  derived ob(3, 4, 5);

  ob.show();  

  return 0;

}