c++ operator+ example
Example 1: Explain operator overloading with an example.
In C++, we can change the way operators work for user-defined types like objects and structures. This is known as operator overloading. For example,
Suppose we have created three objects c1, c2 and result from a class named Complex that represents complex numbers.
Since operator overloading allows us to change how operators work, we can redefine how the + operator works and use it to add the complex numbers of c1 and c2 by writing the following code:
result = c1 + c2;
instead of something like
result = c1.addNumbers(c2);
This makes our code intuitive and easy to understand.
Note: We cannot use operator overloading for fundamental data types like int, float, char and so on.
Syntax for C++ Operator Overloading
To overload an operator, we use a special operator function.
class className {
... .. ...
public
returnType operator symbol (arguments) {
... .. ...
}
... .. ...
};
Example 2: c++ overloaded == operator
#include <iostream>
#include <string>
class Car
{
private:
std::string m_make;
std::string m_model;
public:
Car(const std::string& make, const std::string& model)
: m_make{ make }, m_model{ model }
{
}
friend bool operator== (const Car &c1, const Car &c2);
friend bool operator!= (const Car &c1, const Car &c2);
};
bool operator== (const Car &c1, const Car &c2)
{
return (c1.m_make== c2.m_make &&
c1.m_model== c2.m_model);
}
bool operator!= (const Car &c1, const Car &c2)
{
return !(c1== c2);
}
int main()
{
Car corolla{ "Toyota", "Corolla" };
Car camry{ "Toyota", "Camry" };
if (corolla == camry)
std::cout << "a Corolla and Camry are the same.\n";
if (corolla != camry)
std::cout << "a Corolla and Camry are not the same.\n";
return 0;
}