C-and-C++/C2/Nested-If-And-Switch-Statement/English-timed

Time	Narration
00:01	Welcome to the spoken tutorial on Nested if and Switch statements in C and C++.
00:07	In this tutorial we will learn,
00:09	how to use nested if statement and
00:12	switch statement.We will do this with the help of some examples.
00:17	To record this tutorial, I am using
00:20	Ubuntu operating system version 11.10,
00:24	gcc and g++ Compiler version 4.6.1 on Ubuntu.
00:30	First we will learn how to write nested if and switch statements with an example.
00:36	I have already written the program.
00:39	Let’s have a look. In this program we will learn to check the range of integers.
00:45	Note that our file name is nested-if.c.
00:50	Let me explain the code now.
00:52	This is our Header file.
00:54	This is our main() function.
00:56	Inside the main() function we have declared two integer variables 'x and y'.
01:02	Here we prompt the users to enter a number between the range of 0 to 39.
01:08	We take the value of y as input from the user.
01:12	This is our if condition.
01:14	Here, we will check whether y/10=0.
01:19	If the condition is true, we print "you have entered the number in the range of 0-9".
01:25	This is our else-if condition.
01:28	Here we check that y/10 equals to 1.
01:32	If the condition is true,
01:34	we print "you have entered a number in the range of 10-19".
01:39	In this else if condition we check whether the number is in the range of 20-29.
01:45	And here we will see that the number is in the range of 30 to 39.
01:51	This is our else condition.
01:53	If all of the above conditions are false,
01:55	we print "number not in range".
01:58	And this is our return statement.
02:01	Now let us execute the program.
02:03	Please open the terminal window by pressing Ctrl+Alt and T keys simultaneously on your keyboard.
02:12	To execute, type gcc space nested-if.c space hyphen o space nested. Press Enter.
02:23	Type dot slash “nested” (./nested). Press Enter.
02:28	We see Enter a number between 0 to 39.
02:32	I will enter 12.
02:34	The output is displayed as:
02:35	you have entered the number in the range of 10-19.
02:40	Let us enter another number.
02:42	Let's execute again. Press the up arrow key, press Enter.
02:48	I will give 5 this time.
02:50	We see the output as :
02:52	you have entered the number in the range of 0-9.
02:56	The conditional execution can also be done in another way.
03:00	By using switch statement.
03:02	Let’s see how it is done.
03:05	We will see the same program using switch.
03:08	I have already opened the program.
03:10	Let's switch back to our text editor.
03:13	I have explained this in the previous program.
03:16	So I will move on to the switch statements.
03:20	Here, we divide the inputs i.e y by 10 and the result is stored in the variable x.
03:28	That means the quotient will be stored in x.
03:32	With the help of the quotient we can identify the range of the number.
03:36	Here, we tell the switch command that the variable to be checked is x.
03:41	This is case 0 . If case 0 is satisfied
03:45	then we print you have entered the number in the range of 0-9.
03:51	We add break to come out of the loop if the case is satisfied.
03:55	We need to break the loop each time.
03:58	It is because only one condition can be true at a time.
04:03	This is “case 1”. “case 1” means “if the value of x is 1”.
04:08	We print you have entered a number in the range of 10-19.
04:12	This is “case 2” .
04:14	Here we print you have entered a number in the range of 20-29.
04:20	And this is case 3. Here we check whether the number is in the range of 30-39.
04:26	This is the default case. Default case specifies what needs to be done if none of the above cases are satisfied.
04:36	Here we print "number not in range".
04:39	And This is our return statement.
04:41	Let us execute the program.
04:43	Switch back to the terminal.
04:46	Type gcc space switch.c space -o space switch. Press Enter.
04:55	Type ./switch(dot slash switch). Press Enter.
05:00	Enter a number between 0 to 39. I will enter 35.
05:06	The output is displayed as “you have entered the number in the range of 30 to 39”.
05:10	Now we will see how to execute the programs in C++.
05:16	Switch back to the text editor.
05:18	Note that our file name is nested-if.cpp.
05:23	Here the logic and implementation are same.
05:27	There are a few changes like:
05:30	The header file as "iostream" in place of "stdio.h".
05:35	Here we have included the using statement
05:39	Using namespace std.
05:41	And the cout and cin function in place of printf and scanf.
05:46	You can see that the rest of the code is similar to our C program.
05:51	Let’s execute the code.
05:53	Come back to the terminal.
05:56	Type g++ space nested-if.cpp space -o space nested1. Press Enter.
06:07	Type ./nested1. Press Enter.
06:11	Enter a number between 0 to 39. I will enter 40.
06:16	The output is displayed as: “number not in range”
06:20	Now let’s see the switch program in C++.
06:24	Come back to our text editor.
06:27	Here also the logic and implementation are same.
06:31	You can see that the header file is iostream.
06:34	Here is the using statement.
06:37	And we have changed the cout and cin function.
06:41	Rest of the code is similar to our switch.c program.
06:45	Let us execute.Come back to our terminal.
06:48	Type g++ space switch.cpp space -o space switch1. Press Enter.
06:58	Type ./switch1. Press Enter.
07:02	Enter a number between 0 to 39.
07:05	I will enter 25.
07:09	The output is displayed as:
07:11	“you have entered the number in the range of 20-29”
07:15	Now let us switch back to our slides.
07:18	We will see the comparison between switch and nested-if statements.
07:23	Switch statement is evaluated according to the result of the expression.
07:28	Netsed-if statement is run only if the result of the expression is true.
07:34	In switch, we treat various values of the variable as cases.
07:39	In nested-if we have to write the conditional statement for each value of the variable.
07:45	Switch statement can only check the integer values.
07:50	Nested if can check for both, integer and fractional values.
07:55	This brings us to the end of this tutorial.
07:58	Let us summarize.
08:00	In this tutorial, we learnt * 'nested if' statement. e.g. else if( y/10 equals to 0)
08:08	switch statement. e.g. switch(x) and
08:12	Difference between nested-if and switch statements.
08:16	As an assignment,write a program to check whether the age of the employee is between 20 to 60.
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09:04	The script is contributed by Chaitanya Mokashi. This is Ashwini patil from IIT Bombay signing off. Thank you for joining.

Contributors and Content Editors

Ashwini, Kavita salve, Krupali, PoojaMoolya, Pratik kamble, Priyacst, Sandhya.np14, Sneha