how to do (binary) operator overloading in c++

To overload a binary operator in C++, you need to define a function that implements the desired behavior for the operator. This function is called an overloaded operator function. Here are the steps to perform binary operator overloading in C++:

  1. Define a class: Start by defining a class that will be used to overload the binary operator. This class should contain the data members and member functions required to perform the operation.

  2. Declare the overloaded operator function: Inside the class definition, declare the overloaded operator function using the keyword operator followed by the operator you want to overload. For example, if you want to overload the addition operator +, you would declare the function as operator+.

  3. Implement the overloaded operator function: Outside the class definition, implement the overloaded operator function. The function should take two operands as parameters and return a value of the desired type. The function body should contain the logic to perform the desired operation using the provided operands.

  4. Use the overloaded operator: Once the operator is overloaded, you can use it on objects of the class to perform the desired operation. The overloaded operator will be called automatically when the operator is used with objects of the class.

Here is an example that demonstrates the steps mentioned above:

#include <iostream>

class Complex {
private:
    double real;
    double imag;

public:
    Complex(double r = 0.0, double i = 0.0) : real(r), imag(i) {}

    Complex operator+(const Complex& c) {
        Complex result;
        result.real = real + c.real;
        result.imag = imag + c.imag;
        return result;
    }

    void display() {
        std::cout << real << " + " << imag << "i" << std::endl;
    }
};

int main() {
    Complex c1(2.5, 3.5);
    Complex c2(1.5, 2.5);
    Complex c3;

    c3 = c1 + c2;

    c3.display();

    return 0;
}

In this example, we have defined a class Complex to represent complex numbers. We have overloaded the addition operator + using the operator+ function. Inside the operator+ function, we perform the addition of the real and imaginary parts of the complex numbers and return the result as a new Complex object.

In the main function, we create two Complex objects c1 and c2 and add them using the overloaded + operator. The result is stored in c3 and then displayed using the display member function.

When you run this program, the output will be:

4 + 6i

This demonstrates how to overload the binary addition operator + for the Complex class in C++. You can follow similar steps to overload other binary operators such as subtraction -, multiplication *, and division /, among others.