1. Operator Overloading

2. A+b=ab // String Concatenation
Operator
Syntax:
return_type operator op (argslist) {
function body; }
The Mechanism of providing such an additional meaning to an operator is called operator overloading
Eg: 2+3=5 // addition
A+b=ab // String Concatenation
To pass the value
Class Name
Symbol
(+, -)

3. Need for Operator Overloading
To make the user defined data type as natural as fundamental data type. Here fundamental data type refers int, float, double. User defined data types must be associated with appropriate set of operator
The user can understand the operator notation more easily
It allows the programmer to redefine the meaning of operator when they operate on class objects.
It is used by the programmer to make a program clearer
More readable and array to understand
User don’t need to remember the names of functions

4. Overloading Unary operator
Examples:
An Operator which operates on single variable is called unary operator
A unary operator is a operator that operates on single operand (varibale or numbers)
Eg: -a;
Unary operator have precedence over binary operator
Syntax:
Classname operator - ()
Unary Operator
Description -
Unary minus operator +
Unary Plus operator *
Indirection Operator ++
Incremental
- -
Decremental
Unary minus operator
No arguments

5. Program for Overloading Unary Operator
class sample { public: int a,b; void get() cout<<"Enter values of a & b:"; cin>>a>>b; } sample operator -() // declaring overloading unary operator a=-a; b=-b; void display() cout<<"Unary values for a & b:"<<a<<b; }}; void main() sample g; clrscr(); g.get(); -g; g.display; getch(); Output: Enter values of a & b: 4 8 Unary values for a & b: -4 -8