• OBJECT ORIENTED PROGRAMMING EXAMPLE

  Basic logic gates operations in C++

  // there is a simple object oriented program that will read the input values of different logic gates and show their output values.

  #include <iostream>
  
  using namespace std;
  
  class basic_gate
  {
      //member variables
      bool input1;
      bool input2;
      bool output;
  
  public :
  
  
      basic_gate()//base class constructor for initializing member variables to false
      {
          input1 = false;
          input2 = false;
          output = false;
      }
  
      void set_input(bool a,bool b)//for setting the input
      {
          input1 = a;
          input2 = b;
      }
  
      void set_input(bool a)//overloading set_input()
      {
          input1 = a;
      }
  
      void set_output(bool x)//for setting the output
      {
          output = x;
      }
  
      bool get_input1()//for returning 1st input
      {
          return input1;
      }
  
      bool get_input2()//for returning 2nd input
      {
          return input2;
      }
  
      bool get_output()//for returning the output
      {
          return output;
      }
  
      virtual void operation() = 0;//declaring a pure virtual member function
  
  };
  
  
  class AND_gate : virtual public basic_gate//here base class is inherited as virtual
  {
  
  public :
  
      void operation()//a new definition of operation function
      {
          bool o;
  
          o = this -> get_input1() * this -> get_input2();//processing output
  
          this -> set_output(o);//setting the output
      }
  };
  
  
  class OR_gate : virtual public basic_gate//here the base class is inherited as virtual
  {
  
  public :
  
      void operation()//another definition of operation function
      {
          bool o;
  
          o = this -> get_input1() + this -> get_input2();//processing output
  
          this -> set_output(o);//setting the output
      }
  };
  
  class NOT_gate : virtual public basic_gate//base class is inherited as virtual
  {
  
  public :
  
      void operation()//another definition of operation function
      {
          if(this -> get_input1() == false)
  
              this -> set_output(true);//setting the output
  
          else
  
              this -> set_output(false);
      }
  };
  
  class NAND_gate : public AND_gate , public NOT_gate//this derived class derived from two base classes
  {
  
      void operation()//another definition of operation function
      {
          AND_gate :: operation();
          this -> set_input( this -> get_output() );
          NOT_gate :: operation();
      }
  };
  
  class NOR_gate : public OR_gate , public NOT_gate//this derived class also derived from two base classes
  {
  
      void operation()
      {
          OR_gate :: operation();
          this -> set_input( this -> get_output() );
          NOT_gate::operation();
      }
  };
  
  
  int main()
  {
      bool X,Y;
  
      basic_gate *ptr;//declare a base type pointer
  
      AND_gate A;
  
      ptr = &A;//point the derived class
  
      cout << "Enter the inputs of AND gate:";
      cin >> X >> Y;
  
      ptr -> set_input(X,Y);
      ptr -> operation();
      cout << ptr -> get_output() << endl;
  
      OR_gate B;
      ptr = &B;//point the derived class
  
      cout << "Enter the inputs of OR gate:";
      cin >> X >> Y;
  
      ptr -> set_input(X,Y);
      ptr -> operation();
      cout << ptr -> get_output() << endl;
  
      NOT_gate c;
      ptr = &c;//point the derived class
  
      cout << "Enter the inputs of NOT gate:";
      cin >> X;
  
      ptr -> set_input(X);
      ptr -> operation();
      cout << ptr -> get_output() << endl;
  
      NAND_gate r;
      ptr = &r;//point the derived class
  
      cout << "Enter the inputs of NAND gate:";
      cin >> X >> Y;
  
      ptr -> set_input(X,Y);
      ptr -> operation();
      cout << ptr->get_output() << endl;
  
      NOR_gate z;
      ptr = &z;//point the derived class
  
      cout << "Enter the inputs of NOR gate:";
      cin >> X >> Y;
  
      ptr -> set_input(X,Y);
      ptr -> operation();
      cout << ptr -> get_output() << endl;
  
      return 0;
  }