statfunc.cpp

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// statfunc.cpp
// static functions and ID numbers for objects
#include <iostream>
using namespace std;
////////////////////////////////////////////////////////////////
class gamma
   {
   private:
      static int total;        //total objects of this class
                               //   (declaration only)
      int id;                  //ID number of this object
   public:
      gamma()                  //no-argument constructor
         {
         total++;              //add another object
         id = total;           //id equals current total
         }
      ~gamma()                 //destructor
         {
         total--;
         cout << "Destroying ID number " << id  << endl;
         }
      static void showtotal()  //static function
         {
         cout << "Total is " << total << endl;
         }
      void showid()            //non-static function
         {
         cout << "ID number is " << id << endl;
         }
   };
//--------------------------------------------------------------
int gamma::total = 0;	       //definition of total
////////////////////////////////////////////////////////////////
int main()
   {
   gamma g1;
   gamma::showtotal();

   gamma g2, g3;
   gamma::showtotal();

   g1.showid();
   g2.showid();
   g3.showid();
   cout << "----------end of program----------\n";
   return 0;
   }