Skip to main content

What is reference variable in c++

Hello friends, in this post today, we learn about What is reference variable in c++. and what is its major use in c++. so lets start...

Reference variable in c++,Reference variable
Reference variable in c++




Reference variable:-

Reference variable is a new concept in C++.



A reference variable is a variable which provides an alias (alternative name) for a previously defined variable or any constant.


Reference variable is an internal pointer.


Declaration of reference variable is preceded with & symbol ( but do not read it as ‘address of ‘).


Reference variable must be initialized during declaration.


It can be initialized with already declared variables only.


Reference variables can not be updated.


This mechanism is useful in object oriented programming because it permits the manipulation of objects by reference, and eliminates the copying of object parameters back and forth.


It is also important to note that references can be created not only for built-in data types but also for user- defined data types.


Syntax: Data_type  &reference_name = variable_name;


For example:-         

 100

  int a=100;   

 a,b(456)     int &b=a; //Now both a and b will give same value.


Explanation:-

The statement int &b =a; creates a reference variable b which contains reference of variable a. As mentioned earlier a reference variable has to be initialized. You cannot write int &b. Creating a reference like creating a new name for the same variable so any changes made in b occurs in a and vice versa.


Example:-

#include<iostream>
using namespace std;

int main()
{

int a=100;
int &b=a;  //refence variable
b++;
cout<<"a="<<a<<endl;
cout<<"b="<<b<<endl;
return 0;

}

Output:-

a=101
b=101



I hope that whatever information I have given in this post today, you have liked it and you have understood it.so keep learning and wait for the next post that will help you to increase your knowledge with the something new information.

Thank you so much for reading. And take care about yourself and your family.


Comments

Popular posts from this blog

Constructor in c++

Hello friends, in this post today, we learn about  what is constructor in c++ and types of constructor . so lets start... Constructor in c++ Constructor:-   A constructor is a “special” member function which initializes the objects of class.  Constructor is used to solve problem of initialization. Properties of constructor:- Constructors are used to construct the object of the class. Constructor name must be same as class name. Constructor is invoked automatically when objects of the class are created. The constructors are always declared in the public section. If declared in the private section then objects are can only be created inside the member functions but serve no purpose. It must be an instance member function , that is, it can never be static. Constructors  do not have any return type not even void so they cannot return any value. Constructor can also be overloaded. Constructors cannot be inherited, but they can be called from the constructors of...

Function with Default arguments in c++

Hello friends, i n this post today, we learn about   Function with Default arguments in c++ .  so lets start... Function with default arguments  Function with default arguments:- In C ++ it is possible for a function not to specify all its arguments. Some of the arguments  may be specified their default values at the time of declaring the function.   Default values are specified when the function is declared. We must add default arguments from right to left. We cannot provide a default value to a particular argument in the middle of an argument list. Default arguments are useful in situations where some arguments always have the same value. For Example, passing marks. In a function with default argument, if one argument is default, all successive arguments  must be default. We cannot provide default values in the middle of the arguments or towards  l eft side. We provide few examples: 1. void fun(int x, int y = 20, int z=35); (valid) 2. void fun(int x,...

Pure virtual function in c++

Hello friends, i n this post today, we learn about what is pure virtual  function in c++ and how to use pure virtual function  in c++ .  so lets start... Pure virtual function in c++ Pure virtual function:- A pure virtual function is a function which has its body set to 0 i.e., the pure virtual function  does not have any body. A pure virtual function means ‘do nothing’ function. A function declared in a way: Syntax:- virtual void display() = 0;  is known as pure virtual function. Here = 0 does not mean that function show is equal  to 0. It simply means that the virtual function show has no body.  The pure virtual function act  as an interface and any class which inherits the class in which pure virtual function is present,  has to provide the implementation for the function show. We can say empty function. A pure virtual function has no definition relative to the base class. Programmers have to redefine pure virtual function in derived clas...