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

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Time Narration
00:01 Welcome to the spoken tutorial on Nested if & Switch statements in C and C++.
00:08 In this tutorial we will learn ,
00:11 How to use nested if statement. And
00:14 switch statement.
00:16 We will do this with the help of an examples.
00:20 To record this tutorial, I am using,
00:23 Ubuntu operating system version 11.10
00:27 gcc and g++ Compiler version 4.6.1 on Ubuntu.
00:34 First we will learn, how to write nested if and switch statement with an example.
00:42 I have already written the program
00:44 Let’s have a look
00:49 In this program ,we will learn to check the range of integers.
00:53 Note that our file name is nested-if.c
01:00 Let me explain the code now.
01:03 This is our Header file.


01:05 This is our main function.


01:07 Inside the main function we have declared two integer variable 'x and y'
01:16 Here we prompt the users to enter a number between the range of 0 to 39.
01:23 we take the value of y as input from the user.
01:30 This is our if condition
01:32 Here, we will check whether y/10=0
01:36 If the condition is true
01:38 We print "you have entered a number in the range of 0-9.
01:47 This is our else-if condition.
01:50 Here we check that y/10=1.
01:54 If the condition is true.
01:56 We print you have entered a number in the range of 10-19.
02:03 In this else if condition we check whether the number is in the range of 20-29.
02:11 And here we will see that the number is in the range of 30 to 39.
02:19 This is our else condition.


02:21 If all of the above conditions are false
02:24 We print number not in range.
02:28 And this is our return statement
02:31 Now let us execute the program.
02:35 Please open the terminal window , by pressing Ctrl+Alt+T keys simultaneously on your keyboard.
02:45 To execute , Type “gcc” space “nested-if.c” space hyphen “-o” space “nested”. Press Enter
02:57 type dot slash “./nested”. Press Enter
03:01 We see,Enter a number between 0 to 39.
03:06 I will Enter 12
03:09 The output is displayed as:
03:11 you have entered the number in the range of 10-19.
03:17 Let us enter another number.
03:21 Let's execute again. Press the up arrow key, press enter.
03:28 I will give 5 this time.
03:34 We see the output as :
03:35 you have entered the number in the range of 0-9.
03:42 The conditional execution can also be done in another way.
03:46 By using switch statement.
03:49 Let’s see how it is done.
03:51 We will see the same program using switch.
03:57 I have already opened the program.


03:59 Let's switch back to our text editor
04:07 I have explained this in the previous program.
04:11 So i will move on to the Switch statements


04:16 Here, we divide the inputs i.e y by 10 and the result is stored in the variable x.
04:24 That means the quotient will be stored in x.
04:28 With the help of the quotient we can identify the range of the number.
04:37 Here, we tell the switch command that the variable to be checked is x.
04:47 This is case 0 . If case 0 is satisfied.
04:50 Then we print you have entered the number in the range of0-9.
04:58 We add break to come out of the loop if the case is satisfied.
05:03 We need to break the loop each time.
05:05 It is because only one condition can be true at a time.
05:11 This is “case 1” . “case 1” means “if the value of x is 1”


05:17 We print you have entered a number in the range of 10-19.
05:24 This is “case 2” .
05:26 Here we print you have entered a number in the range of 20-29.
05:33 And this is case 3. Here we check whether the number is in the range of 30-39.
05:43 This is the default case. Default case specifies what needs to be done if none of the above cases are satisfied.
05:52 Here we print number not in range.


05:57 And This is our return statement.
05:59 Let us execute the program.


06:02 Switch back to the terminal.
06:06 Type:gcc switch.c -o switch. Press Enter
06:16 Type:./switch. Press Enter


06:21 Enter a number between of 0 to 39. I willl enter 35
06:28 The output is displayed as,“you have entered the number in the range of 30 to 39”.
06:35 Now we will see how to execute the program in C++.
06:44 Switch back to the text editor.
06:47 Note that our filename is nested-if.cpp
06:55 Here the logic and implementation are same
06:59 There are a few changes like:
07:03 The header file as iostream in place of stdio.h
07:08 Here we have included the using statement.
07:11 Using namespace std
07:14 And the cout and cin function in place of printf and scanf.
07:23 You can see that the rest of the code is similar to our C program.
07:29 Let’s execute the code.
07:31 Come back to the terminal.
07:34 Type: g++ nested-if.cpp -o nested1. Press Enter.
07:45 Type: ./nested1. Press Enter
07:50 enter a number between 0 and 39. I will enter 40.
07:53 The output is displayed as: “number not in range”
08:06 Now let’s see the switch program in C++
08:10 Come back to the text editor.
08:14 Here also the logic and implementation are same.
08:19 You can see that the header file is iostream
08:23 Here is the using statement.
08:25 And we have changed the cout and cin function.
08:33 Rest of the code is similar to our switch.c C program
08:38 Let us execute.
08:40 Come back to the terminal.
08:42 Type:g++ switch.cpp -o switch1 Press Enter
08:52 Type ./switch1. Press Enter
08:57 Enter a number between 0 and 39.
09:00 I will enter 25.
09:04 The output is displayed as:
09:06 “you have entered the number in the range of 20-29”
09:11 Now let us switch back to our slides.
09:16 We will see the comparison between switch and nested-if statement.
09:21 Switch statement is evaluated according to the result of the expression.
09:28 Netsed-if statement is run only if the result of the expression is true.
09:35 In switch we treat various values of the variable as cases.
09:41 In nested-if we have to write the conditional statement for each value of the variable.
09:49 Switch statement can only check the integer values
09:54 Nested if can check for both integer and fractional values.
10:00 This brings us to the end of this tutorial.
10:03 Let us summarize.
10:05 In this tutorial we learnt, nested if statement.
Ex: else if( y/10==0) 
10:13 switch statement.

e.g. Switch(x)

10:16 And Difference between nested-if and switch statements.


10:22 As an assignment,
10:23 Write a program to check whether the age of the employee is between 20 to 60.
10:30 Watch the video available at the link shown http://spoken-tutorial.org /What\_is\_a\_Spoken\_Tutorial
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11:13 The script is contributed by Chaitanya Mokashi. This is Ashwini patil from IIT Bombay signing off. Thank you for joining.