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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.


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