Difference between revisions of "C-and-C++/C2/Logical-Operators/English-timed"

From Script | Spoken-Tutorial
Jump to: navigation, search
Line 9: Line 9:
 
|-
 
|-
 
| 00:08
 
| 00:08
|In this tutorial we will learn about:Logical operators like  Logical AND eg. expression1 && expression2
+
|In this tutorial we will learn about: Logical operators like  Logical AND e.g. expression1 && expression2
  
 
|-
 
|-
Line 29: Line 29:
 
|-
 
|-
 
| 00:28  
 
| 00:28  
|  To record this tutorial, I am using:'''Ubuntu 11.10''' as the operating system  
+
|  To record this tutorial, I am using: '''Ubuntu 11.10''' as the operating system,
  
 
|-
 
|-
 
|00:33
 
|00:33
|'''gcc''' and '''g++ Compiler '''version '''4.6.1 on''' '''Ubuntu.'''
+
|'''gcc''' and '''g++ Compiler '''version '''4.6.1 '''on '''Ubuntu.'''
  
 
|-
 
|-
Line 41: Line 41:
 
|-
 
|-
 
| 00:43
 
| 00:43
|In '''C '''and '''C++,''' '''true''' is any value other than 0.
+
|In '''C '''and '''C++,''' '''true''' is any value other than '''0'''.
  
 
|-
 
|-
 
| 00:48
 
| 00:48
|non zero means true
+
|Non zero means true,
  
 
|-
 
|-
 
| 00:50
 
| 00:50
|And zero means false
+
|and zero means false.
  
 
|-
 
|-
Line 65: Line 65:
 
|-
 
|-
 
| 01:08
 
| 01:08
|  Inside the main block
+
|  Inside the main block,
  
 
|-
 
|-
 
| 01:10
 
| 01:10
|This statement declares the variables '''a''','''b''' and '''c''' as integers.
+
|this statement declares the variables '''a''','''b''' and '''c''' as integers.
  
 
|-
 
|-
Line 89: Line 89:
 
|-
 
|-
 
| 01:38
 
| 01:38
|Here, all of the conditions have to be true for '''logical AND '''to return a true value.
+
|Here, all of the conditions have to be true for '''logical AND '''to return a '''true''' value.
  
 
|-
 
|-
Line 105: Line 105:
 
|-
 
|-
 
| 02:02
 
| 02:02
|This statement is   evaluated if the previous condition is true.  
+
|This statement is evaluated if the previous condition is true.  
  
 
|-
 
|-
Line 149: Line 149:
 
|-
 
|-
 
| 02:57
 
| 02:57
|'''Save''' it with extension '''.c'''
+
|'''Save''' it with extension '''.c''' (dot c).
  
 
|-
 
|-
 
| 03:00
 
| 03:00
|I have saved my file as '''logical.c'''
+
|I have saved my file as '''logical.c'''.
  
 
|-
 
|-
 
| 03:03
 
| 03:03
|  Open the terminal by pressing '''Ctrl, Alt and T '''keys simulataneously.
+
|  Open the terminal by pressing '''Ctrl, Alt''' and '''T '''keys simultaneously.
  
 
|-
 
|-
 
| 03:08
 
| 03:08
|  To compile the code type '''gcc space logical dot c space minus o space  log''' Press enter
+
|  To compile the code type '''gcc space logical dot c space minus o space  log'''. Press Enter
  
 
|-
 
|-
 
| 03:23
 
| 03:23
|To  execute  type '''./log'''
+
|To  execute, type '''./log''' (dot slash log)
  
 
|-
 
|-
 
| 03:27
 
| 03:27
 
|Press '''Enter.'''
 
|Press '''Enter.'''
 
  
 
|-
 
|-
Line 188: Line 187:
 
|-
 
|-
 
| 03:42
 
| 03:42
|c is greatest.  
+
|'''c is greatest'''.  
  
 
|-
 
|-
Line 200: Line 199:
 
|-
 
|-
 
|03:55
 
|03:55
| Now Let's write the same program in C++
+
| Now Let's write the same program in C++.
  
 
|-
 
|-
Line 220: Line 219:
 
|-
 
|-
 
| 04:14
 
| 04:14
|Using statement has been used.
+
|'''using''' statement has been used.
  
 
|-
 
|-
Line 229: Line 228:
 
| 04:21
 
| 04:21
 
|The operators behave in the same way as they did in C.
 
|The operators behave in the same way as they did in C.
 
  
 
|-
 
|-
Line 237: Line 235:
 
|-
 
|-
 
| 04:27
 
| 04:27
| Make sure the file is saved with extension '''.cpp'''
+
| Make sure the file is saved with extension '''.cpp''' (dot cpp).
  
 
|-  
 
|-  
 
|  04:31
 
|  04:31
|  Open the terminal by pressing '''Ctrl, Alt and T '''keys simulataneously.
+
|  Open the terminal by pressing '''Ctrl, Alt''' and '''T '''keys simultaneously.
  
 
|-
 
|-
 
|04:36
 
|04:36
|To compile the program type '''g++ logical.cpp space minus o space log1'''. Press Enter
+
|To compile the program type '''g++ logical.cpp space minus o space log1'''. Press Enter.
  
 
|-
 
|-
 
| 04:49
 
| 04:49
|to execute   type '''./log1'''
+
|To executetype '''./log1''' (dot slash log1).
  
 
|-
 
|-
 
| 04:53
 
| 04:53
 
|press '''Enter.'''
 
|press '''Enter.'''
 
  
 
|-
 
|-
Line 296: Line 293:
 
|-
 
|-
 
| 05:30
 
| 05:30
|Come back to the terminal
+
|Come back to the terminal.
  
 
|-
 
|-
 
| 05:32
 
| 05:32
|Compile and execute as before
+
|Compile and execute as before.
  
 
|-
 
|-
Line 308: Line 305:
 
|-
 
|-
 
| 05:41
 
| 05:41
|Expected identifier before '(' token.
+
|'''Expected identifier before '(' token'''.
  
 
|-
 
|-
 
|  05:45
 
|  05:45
|  This is because we have two different expressions here
+
|  This is because we have two different expressions here.
  
 
|-
 
|-
Line 320: Line 317:
 
|-
 
|-
 
| 05:53
 
| 05:53
|  Now let us go back to our program and fix the error
+
|  Now let us go back to our program and fix the error.
  
 
|-
 
|-
Line 328: Line 325:
 
|-
 
|-
 
| 06:04
 
| 06:04
|Click on '''Save'''
+
|Click on '''Save'''.
  
 
|-
 
|-
Line 336: Line 333:
 
|-
 
|-
 
|  06:09
 
|  06:09
| Compile and execute as before
+
| Compile and execute as before.
  
 
|-
 
|-
Line 349: Line 346:
 
| 06:24
 
| 06:24
 
| In this tutorial we learnt about  Logical AND eg. '''((a > b) && (a > c)) '''
 
| In this tutorial we learnt about  Logical AND eg. '''((a > b) && (a > c)) '''
 
 
   
 
   
 
|-
 
|-
Line 356: Line 352:
  
 
eg. '''(a == 0 || b == 0 || c == 0) '''
 
eg. '''(a == 0 || b == 0 || c == 0) '''
 
  
 
|-
 
|-
 
| 06:39
 
| 06:39
|Assignment
+
|Assignment,
  
 
|-
 
|-
Line 372: Line 367:
 
|-
 
|-
 
| 06:54
 
| 06:54
|  Watch the video available at the following link  
+
|  Watch the video available at the following link.
  
 
|-
 
|-
 
| 06:57
 
| 06:57
|It summarises the Spoken Tutorial project  
+
|It summaries the Spoken Tutorial project.
  
 
|-
 
|-
 
| 06:59
 
| 06:59
|If you do not have good bandwidth, you can download and watch it  
+
|If you do not have good bandwidth, you can download and watch it.
 
+
 
+
  
 
|-
 
|-
 
|  07:03
 
|  07:03
| The Spoken Tutorial Project Team * Conducts workshops using spoken tutorials  
+
| The Spoken Tutorial Project Team : Conducts workshops using spoken tutorials.
  
 
|-
 
|-
 
| 07:07
 
| 07:07
| Gives certificates for those who pass an online test  
+
| Gives certificates for those who pass an online test.
  
 
|-
 
|-
 
| 07:11
 
| 07:11
| For more details, please write to contact at spoken hyphen tutorial dot org  
+
| For more details, please write to contact at spoken hyphen tutorial dot org.
  
 
|-
 
|-
 
| 07:18
 
| 07:18
|  Spoken Tutorial Project is a part of the Talk to a Teacher project  
+
|  Spoken Tutorial Project is a part of the Talk to a Teacher project.
 
|-
 
|-
 
| 07:21
 
| 07:21
|It is supported by the National Mission on Education through ICT, MHRD, Government of India  
+
|It is supported by the National Mission on Education through ICT, MHRD, Government of India.
  
 
|-
 
|-
Line 409: Line 402:
 
|-
 
|-
 
| 07:30
 
| 07:30
| spoken hyphen tutorial dot org slash NMEICT hyphen Intro  
+
| spoken hyphen tutorial dot org slash NMEICT hyphen Intro.
 
+
 
+
  
 
|-
 
|-

Revision as of 14:38, 5 February 2015

Time Narration
00:02 Welcome to the spoken tutorial on Logical operators in C and C++.
00:08 In this tutorial we will learn about: Logical operators like Logical AND e.g. expression1 && expression2
00:16 Logical OR

eg. expression1 or expression2

00:21 Logical NOT

eg. not (Expression1)

00:25 We will do this with the help of examples.
00:28 To record this tutorial, I am using: Ubuntu 11.10 as the operating system,
00:33 gcc and g++ Compiler version 4.6.1 on Ubuntu.
00:39 Let us start with the introduction to the logical operators.
00:43 In C and C++, true is any value other than 0.
00:48 Non zero means true,
00:50 and zero means false.
00:53 Expressions using logical operators return 1 for true and 0 for false.
00:58 Now I'll explain the logical operators with the help of an example.
01:03 Here is the program for logical operators in C.
01:08 Inside the main block,
01:10 this statement declares the variables a,b and c as integers.
01:16 The printf statement prompts the user to enter the values of a,b and c.
01:21 The scanf statement takes input from the user for variables a, b and c.
01:28 Here, We are comparing the values of a with b and c to find the greatest.
01:33 To compare simultaneously, we use the logical AND operator.
01:38 Here, all of the conditions have to be true for logical AND to return a true value.
01:43 The expression is not evaluated further on encountering a false condition.
01:49 So, the expression (a>c) is evaluated only if (a>b) is true.
01:56 If a is less than b, then the expression won't be evaluated further.
02:02 This statement is evaluated if the previous condition is true.
02:07 Next (b>c) is evaluated.
02:10 If the condition is true, then b is greatest is displayed on the screen.
02:16 Otherwise c is greatest is displayed on the screen.
02:21 We now come to the logical OR operator.
02:24 Here, any one of the conditions has to be true for logical OR to return a true value.
02:30 The expression is not evaluated further on encountering a true condition.
02:35 So, if a == zero, then the remaining two expressions won't be evaluated.
02:43 This printf statement is executed if either of a, b or c is 0.
02:49 Coming to the end of the program. return 0 and ending curly bracket.
02:54 Now save the program.
02:57 Save it with extension .c (dot c).
03:00 I have saved my file as logical.c.
03:03 Open the terminal by pressing Ctrl, Alt and T keys simultaneously.
03:08 To compile the code type gcc space logical dot c space minus o space log. Press Enter
03:23 To execute, type ./log (dot slash log)
03:27 Press Enter.
03:29 I will enter the values as,

0

34

567

03:39 The output is displayed as,
03:42 c is greatest.
03:45 The product of a, b and c is zero.
03:50 You should try executing this program with different sets of inputs.
03:55 Now Let's write the same program in C++.
03:59 I have already made the program and will take you through it.
04:03 Here is the code in C++.
04:06 Now to make the same program in C++, we make a few changes.
04:11 There's a change in the header file.
04:14 using statement has been used.
04:18 Also there is a difference in output and input statements.
04:21 The operators behave in the same way as they did in C.
04:25 Click on Save.
04:27 Make sure the file is saved with extension .cpp (dot cpp).
04:31 Open the terminal by pressing Ctrl, Alt and T keys simultaneously.
04:36 To compile the program type g++ logical.cpp space minus o space log1. Press Enter.
04:49 To execute, type ./log1 (dot slash log1).
04:53 press Enter.
04:56 I will enter the values as

0

34

567

05:02 So we see the output is similar to the C program.
05:05 You should try executing the program with different sets of inputs too.
05:10 Now let us see an error which we can come across.
05:12 Let's switch to the editor.
05:16 Suppose here we forgot the brackets.
05:20 Delete this and this.
05:26 Let see what will happen, Save the program.
05:30 Come back to the terminal.
05:32 Compile and execute as before.
05:38 We see the error:
05:41 Expected identifier before '(' token.
05:45 This is because we have two different expressions here.
05:48 We have to evaluate them as one expression using AND operator.
05:53 Now let us go back to our program and fix the error.
05:57 Let us insert the brackets here and here.
06:04 Click on Save.
06:06 Come back to the terminal.
06:09 Compile and execute as before.
06:14 So it is working now.
06:22 Let us now summarize the tutorial.
06:24 In this tutorial we learnt about Logical AND eg. ((a > b) && (a > c))
06:32 Logical OR

eg. (a == 0 || b == 0 || c == 0)

06:39 Assignment,
06:41 Write a program that takes two numbers as input from the user.
06:44 Check whether the two numbers are equal or not using NOT operator. Hint: (a != b)
06:54 Watch the video available at the following link.
06:57 It summaries the Spoken Tutorial project.
06:59 If you do not have good bandwidth, you can download and watch it.
07:03 The Spoken Tutorial Project Team : Conducts workshops using spoken tutorials.
07:07 Gives certificates for those who pass an online test.
07:11 For more details, please write to contact at spoken hyphen tutorial dot org.
07:18 Spoken Tutorial Project is a part of the Talk to a Teacher project.
07:21 It is supported by the National Mission on Education through ICT, MHRD, Government of India.
07:27 More information on this Mission is available at
07:30 spoken hyphen tutorial dot org slash NMEICT hyphen Intro.
07:37 This is Ritwik Joshi from IIT Bombay.

Thank you for joining.

Contributors and Content Editors

Ashwini, PoojaMoolya, Pratik kamble, Sandhya.np14