The document discusses operator overloading in C++. It defines operator overloading as changing the definition of an operator so it can be applied to class objects. Only existing operators can be overloaded and the overloaded operator must have at least one user-defined type operand. An example overloads the [] operator for an Array class to allow accessing elements using A[i] syntax.

1. Name: Shubham Vishwambhar
Course: B.Tech Computer(BAO)
Year: 2nd
Subject: Object-oriented programming (OOP)
Topic: Operator Overloading

2. • INDEX
 Introduction
 Types of Operator
 Rules for Operator Overloading
 Example of Operator Overloading

3. • Introduction
 Changing the definition of an operator so it can be
applied on the objects of a class is called operator
overloading.
 To overload an operator, we need to write a function for
the operator we are overloading.

4. • Rules For Overloading Operators
 Only existing operators can be overloaded. New operators
cannot be created.
 The overloaded operator must have at least one operand
that is of user-defined type.
 We cannot change the basic meaning of an operator.
 Overloaded operators follow the syntax rules of the
original operators.

5. • Example:
overloading the [] operator
class Array {
private:
int num;
int *arr;
public:
Array(int); //constructor
~Array(); // destructor
int& operator[](int);
};
Array::Array(int n)
{
num=n;
arr=new int[n];
}
Array::~Array()
{
delete[]arr;
}

6. int& Array::operator[](int index)
{
if ((index < 0) || (index >= num)) {
cout << "Out of bounds error !!" << endl;
exit(0); // error: invalid index !!
}
else
return(arr[index]);
}
void main()
{
int i;
Array A(10);
for(i=0; i<=10; i++) // i=10: error !!
A[i] = i;
}

7. ANY QUESTIONS ?

8. THANK YOU !