Tutorial - C / C++ - Operator

#include <iostream>

using namespace std;

class optest
{
public :
       int i ;
       optest() { i = 0; }
       optest(int i2) { i = i2;}
       
       virtual int out() { return i;}

       int operator +(int addi)
       {
              return i + addi;
       }

       int operator++(int)
       {
              return ++i;
       }

       int operator &(int addi)
       {
              return i&addi;
       }
};

class optest2 : public optest       // inhert the base class for showing how to use operators within base class and inherited classes
{
public:
       int out() { return i + 10;}
       optest2() : optest() {;}
       optest2(int i) : optest(i) {;}
};

int main(int argc, char* argv[])
{
       // setup and demo the results of the operators
       optest op(3);
       optest2 op2(2);
       cout << op.out() << endl;
       cout << op + 3 << endl;
       cout << op.out() << endl;
       cout << op++ << endl;
       cout << op.out() << endl;
       cout << op2.out() << endl;
       return 0;
}