countpp3.cpp

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// countpp3.cpp
// increment counter variable with ++ operator
// uses unnamed temporary object
#include <iostream>
using namespace std;
////////////////////////////////////////////////////////////////
class Counter
   {
   private:
      unsigned int count;        //count
   public:
      Counter() : count(0)       //constructor  no args
         {  }
      Counter(int c) : count(c)  //constructor, one arg
         {  }
      int get_count()            //return count
         { return count; }
      Counter operator ++ ()     //increment count
         {
         ++count;                //increment count, then return
         return Counter(count);	//  an unnamed temporary object
         }                       //  initialized to this count
   };
////////////////////////////////////////////////////////////////
int main()
   {
   Counter c1, c2;                       //c1=0, c2=0

   cout << "\nc1=" << c1.get_count();    //display
   cout << "\nc2=" << c2.get_count();

   ++c1;                                 //c1=1
   c2 = ++c1;                            //c1=2, c2=2

   cout << "\nc1=" << c1.get_count();    //display again
   cout << "\nc2=" << c2.get_count() << endl;
   return 0;
   }