Defining operator overloading

📘 What is Operator Overloading?

Operator Overloading is a feature in C++ that allows you to redefine the meaning of operators (like +, -, *, etc.) for user-defined data types (like classes).

It makes objects of a class behave like built-in types when used with standard operators.

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🧠 Real-Life Analogy:

Just like + means addition for integers and concatenation for strings, we can define what + should do for a class like Complex, Time, or Vector.

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🔧 Syntax of Operator Overloading

Operator overloading is done using a special function:

return_type operator op (arguments) {
    // body of the function
}

Here:

• op is the operator to overload (like +, -, ==, etc.)
• operator is a keyword
• Can be a member function or a friend function

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📌 Types of Operators That Can Be Overloaded:

• Arithmetic: +, -, *, /
• Comparison: ==, !=, <, >
• Assignment: =
• Unary: ++, --
• Others: [], (), ->

❌ Some operators cannot be overloaded: ::, ., .*, sizeof, ?:

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🧪 C++ Program: Overloading + Operator for Complex Numbers

#include <iostream>
using namespace std;

class Complex {
private:
    float real;
    float imag;

public:
    Complex() : real(0), imag(0) {}

    Complex(float r, float i) {
        real = r;
        imag = i;
    }

    // Overload + operator
    Complex operator + (Complex c) {
        Complex temp;
        temp.real = real + c.real;
        temp.imag = imag + c.imag;
        return temp;
    }

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

int main() {
    Complex c1(3.5, 2.5);
    Complex c2(1.5, 4.5);

    Complex c3 = c1 + c2;  // Uses overloaded + operator

    cout << "Sum of Complex Numbers: ";
    c3.display();

    return 0;
}

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✅ Output:

Sum of Complex Numbers: 5 + 7i

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🎯 Key Points:

• operator+ is a member function that defines how to add two Complex objects.
• When c1 + c2 is executed, it calls c1.operator+(c2) behind the scenes.
• Makes code more intuitive and object-oriented.

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✅ Advantages:

• Makes code easier to read and more natural.
• Enhances usability of custom classes.
• Allows mathematical operations on objects.

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❌ Limitations:

• Can be misused to make code confusing.
• Must be used carefully to maintain meaning and readability.

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📌 Summary:

Concept	Explanation
Operator Overloading	Redefining the functionality of operators
Purpose	To use operators with user-defined types
Example Used	+ for adding Complex numbers
Benefit	More natural and readable code