Complex code of operator overloading in C++

#include "iostream.h"
#include "conio.h"
class test
{
  private:int a;
                 int b;
  public:void getdata()
                {
                                 a=10;
                                 b=10;
                };
                void putdata()
                {
                                 cout<<a;
                                 cout<<b;
                };
                void operator-()
                {
                                 a=-a;
                                 b=-b;
                };


};
main()
{
test t;
t.getdata();
-t;
t.putdata();
 getch();
}
Ans:-    -10    -10
Discussion:-Here –(Ve) operator is overloading. And it changes the sign of a and b.


Q2)Output of the program
#include "iostream.h"
#include "conio.h"
class test
{
  private:int a;
                 int b;
  public:void getdata()
                {
                                 a=10;
                                 b=10;
                };
                void putdata()
                {
                               cout<<a;
                                 cout<<b;
                };
                void operator::()
                {
                                 a=-a;
                                 b=-b;
                };


};

main()
{
test t;
t.getdata();
::t;
t.putdata();
 getch();
}
Ans:-Compile time error.
Discussion:-Here ::  (Scope resolution) operator is trying to overload. But it not possible to overload scope resolution operator.


Q3)Output of the program.
#include "iostream.h"
#include "conio.h"
class test
{
  private:int a;
                 int b;
  public:void getdata()
                {
                                 a=10;
                                 b=10;
                };
                void putdata()
                {
                                 cout<<a;
                               cout<<b;
                };
                test operator+(test t)
                {
                                 test temp;
                                 temp.a=a+t.a;
                                 temp.b=b+t.b;
                                 return temp;
                };


};

main()
{
test t1,t2,t3;
t1.getdata();
t2.getdata();
t3=t1+t2;
t3.putdata();
 getch();
}
Ans:-20 20
Discussion:-Here binary (+) operator is overloaded. And It adding two object  t 1 and t2.