Operator overloading is the process of defining new meanings for operators based on operand types, allowing user-defined data types to be processed. It is achieved by declaring a special member function in a class using the operator keyword, which can overload unary and binary operators. Examples provided show how to overload operators such as ++ and + to work with objects of user-defined classes in C++.

2. Operator Overloading
 The process of defining additional meaning to an operator is called
operator overloading.
 It enables the operator to perform different operations depending on the
type of operands.
 It also enable the operators to process the user defined data types.

3. Example:
 The addition operator is used to add tow numeric values. Suppose a, b and
c are three integer variables. The following statement will add the
contents of a and b and store the result in variable c.
c = a + b;
 The addition operator already know how to process the integer operands.

4. Continue…
 But it does not know how to process to user defined objects. The above
statement generates an error if a, b and c are objects of a class. However,
operator overloading can enable the addition operator to manipulate two
objects.

5. Overloading an Operator
 An operator can be overloaded by declaring a special member function in
the class. The member function uses the keyword operator with the
symbol of operator to be overloaded.

6. Syntax:
 The syntax of overloading an operator is as follows:
return_type operator op()
{
function body;
}
Return_type: It indicates the type of value returned by the member
function.
Operator: It is the keyword that indicates that the member function is
used to overload an operator
Op: It is the symbol of an operator to be overloaded.

7. Overloading Unary Operators
 A type of operator that works with single operands is called unary
operator. The unary operators are overloaded to increase their
capabilities.
 The unary operators that can be overloaded in OOP using c++ are as
follows:
++ -- () -> new delete

8. Example: Overloading ++ operator
#include<iosteam> void operator ++()
Class count {
{ n = n+1;
private: }
int n; };
public: int main()
count() {
{ count obj;
n = 0; obj.show();
} ++obj;
void show() obj.show();
{ getch();
cout<<“n=”<<n<<endl; }
}

9. How above Program Works?
 The above program overloads the increment operator ++ to work to work
with all objects of user defined class count. It increases the value of data
member by 1. The user can use the same format to increase the value of
an object as used with integers.

10. Operator Overloading with returned value
 The increment operator can be used in assignment operator to store the
incremented value in another variable.
 Suppose a and b are two integers, the following statement will increment
the value of a by 1 then assign the value to b
b = ++a;
The above functionality can be assigned to the operator by returning the
new value from member function. The returned value can be stored in
another object of the same type on the left side of the assignment operator

11. Example:
#include<iostream>
class count
{
private:
int n, name ,rol_no;
public:
count()
{
n = 0;
}
void show()
{
cout<<“n=“<<n<<endl;
}
count operator ++()
{
count temp;
n = n+ 1;
temp.n = n;
return temp;
}
};
int main()
{
count x , y;
x.show();
y.show();
y = ++x;
x.show();
y.show();
}

12. Overloading Binary Operators
 A type of operators that works that works with operand is called binary
operators. These operators are overloaded to increase their capabilities.
 The binary operators that can be overloaded in OOP using c++ are as
follows:
== += + - * / % & << >>
-=

13. Example:
#include<iostream>
class add
{
private:
int a , b;
public:
add()
{
a = b = 0;
}
void input()
{
cout<<“ENTER a = “;
cin>>a;
cout<<“ENTER b = “;
cin>>b ;
}
void show()
{
cout<<“a=“<<a<<endl;
cout<<“b=“<<b<<endl;
}
add operator +(add p)
{
add temp;
temp.a = p.a+a;
temp.b = p.b+b;
return temp;
}
};

14. int main()
{
add x,y,z;
x.input();
y.input();
z = x + y;
x.show();
y.show();
z.show();
}