Advantages and Disadvantages of Friend Function in C++

We have created the friend function to access the different modifiers in C++ Object Oriented Programming System such as Protected, Private and Public. The friend function or the friend class will usually be defined outside the course but still has access to the class's private, protected and public members defined in the class code.

Advantages	Disadvantages
The declaration can be anywhere in the code	It is not passed to the derived class
There is no need to create an object to call it.	They don't have a storage-specified class.
Non-public members of the class can also be accessed using the friend function.	The friend function comes in handy when multiple classes are tied together.
It can add extra functionality.	Allows private and protected members to be shown as the information of the class.
Enables programming experience to be more efficient than ever before.	It can have both public and private protected members in the same class in which it has been defined.

C++ code

// below, we are writing down the C++ programming language code to 
// demonstrate the concept of Advantage and disadvantage friend function C++
// which depicts how the friend function can act as a bridge between classes
#include<iostream>
using namespace std;


// the below class declaration is a forward declaration
class JTP;
class XYZ
{
	int x;
	public:
		void set_data(int a)
		{
			x=a;
		}
		
		friend void max(XYZ, JTP);
};


class JTP {
	int y;
	public:
		void set_data(int a)
		{
			y=a;
		}	
		
	friend void max(XYZ, JTP);
};

void max(XYZ t1,JTP t2)
{
	if(t1.x>t2.y)
		cout<<t1.x;
	else
		cout<<t2.y;
}

// the driver code functionality starts from here
int main()
{
	JTP _abc;
	XYZ _xyz;
	_xyz.set_data(120);
	_abc.set_data(3135);
	
	// the below code snippet helps us with calling down the friend
	// function which we have declared to perform operations
	max(_xyz,_abc); 
	return 0;
}

Output:

/tmp /mB gjSey FC Z.o
3135

C++ code

// below, we are writing down the C++ programming language code to 
// demonstrate the concept of Advantage and disadvantage friend function C++
// which depicts how the friend function can act as a bridge between classes
#include<iostream>
using namespace std;

// defining class A from here
class A
{
	int x;
		public:
			
	A()
	{
		x=3979;
	}
	// the below small code snippet is enough to define the 
	// friend class for our code to demonstrate the usage of class B
	friend class B; 
};
// defining class B from here
class B
{
	public:
		void display(A &t)
		{
			cout<<endl<<"After performing the operations the value for X we have got as: "<<t.x;
		}
};

// the driver code functionality starts from here
main()
{
	A _a;
	B _b;
	_b.display(_a);
	return 0;
}

Output:

/tmp /mB gjSey FC Z.o
After performing the operations, the value for X we have got is 3979

C++ code

// below, we are writing down the C++ programming language code to 
// demonstrate the concept of Advantage and disadvantage friend function C++
// which depicts how the friend function can act as a bridge between classes
// and to find the largest of two numbers using the friend function method

#include<iostream>
using namespace std;

class Largest
{
    // declaring the variables a,b and m for performing the operations
	int a,b,m;
	public:
		void set_data();
		friend void find_max(Largest);	
};

// writing the void function to take the inputs from the user without 
// writing them again and again from the int main function
void Largest::set_data()
{
    // string display to ask the user to give the input
	cout<<"Dear User, please enter the value for the variable first no: ";
	cin>>a;
	cout<<"Dear User, please enter the value for the variable second no: ";
	cin>>b;
}


// function, which calculates the largest among the inputs entered by the 
// user
void find_max(Largest t)
{
	if(t.a>t.b)
		t.m=t.a;
	else
		t.m=t.b;
		
		Cout <<"Hey! User, the maximum number among the inputs entered by you is: "<<t.m;
}

// the driver code functionality starts from here
main()
{
	Largest l;
	l.set_data();
	find_max(l);
	return 0;
}

Output:

/tmp /mB gjSey FC Z.o
Dear User, please enter the value for the variable first no: 35
Dear User, please enter the value for the variable second no: 365
Hey! User, the maximum number among the inputs entered by you is: 365

Next TopicC++ Pre-processors

← prev next →

For Videos Join Our Youtube Channel: Join Now

Feedback

Send your Feedback to [email protected]

Help Others, Please Share

Learn Latest Tutorials

Splunk

SPSS

Swagger

Transact-SQL

Tumblr

ReactJS

Regex

Reinforcement Learning

R Programming

RxJS

React Native

Python Design Patterns

Python Pillow

Python Turtle

Keras

Preparation

Aptitude

Reasoning

Verbal Ability

Interview Questions

Company Questions

Trending Technologies

Artificial Intelligence

AWS

Selenium

Cloud Computing

Hadoop

ReactJS

Data Science

Angular 7

Blockchain

Git

Machine Learning

DevOps

B.Tech / MCA

DBMS

Data Structures

DAA

Operating System

Computer Network

Compiler Design

Computer Organization

Discrete Mathematics

Ethical Hacking

Computer Graphics

Software Engineering

Web Technology

Cyber Security

Automata

C Programming

C++

Java

.Net

Python

Programs

Control System

Data Mining

Data Warehouse

Javatpoint Services

JavaTpoint offers too many high quality services. Mail us on [email protected], to get more information about given services.

Website Designing
Website Development
Java Development
PHP Development
WordPress
Graphic Designing
Logo
Digital Marketing
On Page and Off Page SEO
PPC
Content Development
Corporate Training
Classroom and Online Training
Data Entry

Training For College Campus

JavaTpoint offers college campus training on Core Java, Advance Java, .Net, Android, Hadoop, PHP, Web Technology and Python. Please mail your requirement at [email protected].
Duration: 1 week to 2 week

^{Like/Subscribe us for latest updates or newsletter}

C++ Tutorial

C++ Control Statement

C++ Functions

C++ Arrays

C++ Pointers

C++ Object Class

C++ Inheritance

C++ Polymorphism

C++ Abstraction

C++ Namespaces

C++ Strings

C++ Exceptions

C++ Templates

Signal Handling

C++ File & Stream

C++ Misc

C++ STL Tutorial

C++ Iterators

C++ Programs

MCQ

Interview Question

Advantages and Disadvantages of Friend Function in C++

Feedback

Help Others, Please Share

Learn Latest Tutorials

Preparation

Trending Technologies

B.Tech / MCA

Javatpoint Services

Training For College Campus