برنامه ای به زبا سی پلاس پلاس برای بررسی عملگر افزایشی ++ و کاهشی -- بعد و قبل از یک متغیر

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/* C++ program to demonstrate the working of ++ operator overlading. */

#include <iostream>
using namespace std;
class Check
{
  private:
    int i;
  public:
    Check(): i(0) {  }
    Check operator ++() /* Notice, return type Check*/
    {
       Check temp;  /* Temporary object check created */
       ++i;         /* i increased by 1. */
       temp.i=i;   /* i of object temp is given same value as i */
       return temp; /* Returning object temp */
    }
   void Display()
      { cout<<"i="<<i<<endl; }
};
int main()
{
    Check obj, obj1;
    obj.Display();
    obj1.Display();
    obj1=++obj;
    obj.Display();
    obj1.Display();
    return 0;
}

Output

i=0
i=0
i=1
i=1

Operator Overloading of Postfix Operator:

/* C++ program to demonstrate the working of ++ operator overlading. */

#include <iostream>
using namespace std;
class Check
{
  private:
    int i;
  public:
    Check(): i(0) {  }
    Check operator ++ ()
    {
        Check temp;
        temp.i=++i;
        return temp;
    }

/* Notice int inside barcket which indicates postfix increment. */
    Check operator ++ (int)
    {
        Check temp;
        temp.i=i++;
        return temp;
    }
   void Display()
      { cout<<"i="<<i<<endl; }
};
int main()
{
    Check obj, obj1;    
    obj.Display(); 
    obj1.Display();
    obj1=++obj;     /* Operator function is called then only value of obj is assigned to obj1. */
    obj.Display();
    obj1.Display();
    obj1=obj++;     /* Assigns value of obj to obj1++ then only operator function is called. */
    obj.Display();
    obj1.Display();
    return 0;
}

Output

i=0
i=0
i=1
i=1
i=2
i=1