Advanced-C++/C2/Friend-Function/English-timed

Time	Narration
00:01	Welcome to the spoken tutorial on Friend Function in C++.
00:06	In this tutorial, we will learn
00:08	Friend function.
00:10	We will do this with the help of an example.
00:13	To record this tutorial, I am using:
00:15	* Ubuntu OS version 11.10
00:19	* g++ compiler version 4.6.1
00:24	Let us start with an introduction to friend function.
00:27	We know, the private data is not accessible outside the class.
00:33	To access the private data, we use friend function.
00:37	A friend function is not a member function of the class.
00:42	Friend function can be invoked without using an object.
00:46	The argument passed in the friend function is used as its object.
00:51	Let us see the declaration of a friend function.
00:55	friend keyword is used to declare a friend function.
00:59	Then we give the return_type.
01:02	function_name is the name of the function.
01:05	Then we pass arguments as class_name and object of the class.
01:11	Let us look at an example.
01:13	I have already typed the code on the editor.
01:16	I will open it.
01:18	In this program, we will perform addition operation.
01:22	Note that our file-name is frnd.cpp.
01:27	Let me explain the code now.
01:30	This is our header file as iostream.
01:34	Here we are using std namespace.
01:37	Then we have declared a class frnd.
01:41	In this, we have declared variables 'a' and 'b' as private.
01:46	Here we have declared a function input() as public.
01:52	In this, we take input from the user.
01:55	This is our friend function as compute().
01:58	Here, we have passed arguments as class_name frnd and object of the class 'f1' .
02:06	Then we close the class.
02:08	Now, we can access the private members of class frnd using the friend function.
02:16	Here, we have used the compute() function.
02:19	In this, we will perform addition operation.
02:23	We add the variables 'a' and 'b'.
02:26	And then return the value.
02:28	Here, we access the private variables in non-member function using the object f1.
02:35	This is our main() function.
02:38	In this, we create an object of class frnd as f.
02:44	Then we call the function input() using the object f.
02:48	And here, we call function compute() and pass f as argument.
02:54	You can see that we have passed the argument as f in function compute().
02:58	This is done by using the method pass by value.
03:03	f is passed to the value of f1.
03:06	And this is our return statement.
03:09	Now, let us execute the program.
03:11	Open the terminal window by pressing Ctrl, Alt and T keys simultaneously on your keyboard.
03:20	Now type:
03:21	g++ space frnd dot cpp space hyphen o space frnd. Press Enter.
03:32	Type: dot slash frnd
03:36	press Enter.
03:38	Here, it is displayed as: Enter the value of a and b.
03:41	I will enter as: 8 and 4.
03:46	The output is displayed as:
03:48	The result is: 12.
03:51	This brings us to the end of this tutorial.
03:54	Let us move back to our slides.
03:56	Let us summarize.In this tutorial, we learned Friend function. e.g. friend int compute class-name frnd and object 'f1' .
04:08	As an assignment, write a program to find out the square and cube of a number.
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04:56	This is Ashwini Patil from IIT Bombay, signing off.Thank You for joining.

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Gaurav, PoojaMoolya, Pratik kamble, Sandhya.np14