Difference between revisions of "C-and-C++/C2/First-C++-Program/English-timed"

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{| border=1
 
{| border=1
|| ''Time'''
+
||'''Time'''
 
|| '''Narration'''
 
|| '''Narration'''
 +
 
|-
 
|-
| 00.02
+
| 00:02
| Welcome to the spoken tutorial on First C++ program.  
+
| Welcome to the spoken tutorial on '''First C++ program'''.  
  
 
|-
 
|-
| 00.07
+
| 00:07
| In this tutorial I am going to explain,  
+
| In this tutorial I am going to explain,  
  
 
|-
 
|-
| 00.10
+
| 00:10
| How to write a C++ program
+
|How to write a C++ program
  
 
|-
 
|-
| 00.13
+
| 00:13
| How to compile it
+
|How to compile it, How to execute it
 
+
|-
+
| 00.14
+
| How to execute it
+
  
 
|-
 
|-
| 00.17
+
| 00:17
 
| We will also explain some common errors and their solution.  
 
| We will also explain some common errors and their solution.  
  
 
|-
 
|-
| 00.22
+
| 00:22
| To record this tutorial, I am using Ubuntu operating system version 11.10 and  
+
| To record this tutorial, I am using Ubuntu operating system version 11.10 and  
  
 
|-
 
|-
| 00.29
+
| 00:29
| G++ Compiler version 4.5.2 on Ubuntu.
+
| G++ Compiler version 4.5.2 on Ubuntu.
  
 
|-
 
|-
| 00.35
+
| 00:35
| To practice this tutorial,  
+
| To practice this tutorial,  
  
 
|-
 
|-
| 00.37
+
| 00:37
 
| You should be familiar with Ubuntu Operating System and an Editor
 
| You should be familiar with Ubuntu Operating System and an Editor
  
 
|-
 
|-
| 00.44
+
| 00:44
|Some editors are vim and gedit
+
|Some editors are 'vim' and 'gedit'.
  
 
|-
 
|-
| 00.48
+
| 00:48
| I am using gedit in this tutorial
+
| I am using 'gedit' in this tutorial.
  
 
|-
 
|-
| 00.50
+
| 00:50
| For relevant tutorial Please visit our website which is as shown  
+
| For relevant tutorial please visit our website which is as shown.
  
 
|-
 
|-
| 00.56
+
| 00:56
| Let me tell you how to write a C++ program through an example  
+
| Let me tell you how to write a C++ program through an example.
  
 
|-
 
|-
| 01.01
+
| 01:01
 
| Open the  terminal Window using '''Ctrl,  Alt and T keys''' simultaneously on your keyboard.
 
| Open the  terminal Window using '''Ctrl,  Alt and T keys''' simultaneously on your keyboard.
  
 
|-
 
|-
| 01.09
+
| 01:09
 
| To open the text editor, type on the terminal.
 
| To open the text editor, type on the terminal.
  
 
|-
 
|-
| 01.13
+
| 01:13
 
| '''“gedit”''' space '''“talk”''' dot '''“.cpp”''' space ampersand '''“&”''' sign.
 
| '''“gedit”''' space '''“talk”''' dot '''“.cpp”''' space ampersand '''“&”''' sign.
  
 
|-
 
|-
| 01.21
+
| 01:21
 
| We use the '''“&”''' to free up the prompt.
 
| We use the '''“&”''' to free up the prompt.
  
 
|-
 
|-
| 01.25
+
| 01:25
| Please note that all the C++ files will have the extension '''“.cpp”'''
+
| Please note that all the C++ files will have the extension '''“.cpp”'''.
  
 
|-
 
|-
| 01.31
+
| 01:31
| Now  Press '''Enter'''
+
| Now  Press '''Enter''',
  
 
|-
 
|-
| 01.33
+
| 01:33
|the text editor has opened.  
+
| the text editor has opened.  
  
 
|-
 
|-
| 01.35
+
| 01:35
| Let us start to write a program.
+
| Let us start to write a program.
  
 
|-
 
|-
| 01.38
+
| 01:38
 
| Type double slash '''“//”''' space '''“My first C++ program”.'''
 
| Type double slash '''“//”''' space '''“My first C++ program”.'''
 
  
 
|-
 
|-
| 01.44
+
| 01:44
| Here, double slash is used to comment the line
+
| Here, double slash is used to comment the line.
  
 
|-
 
|-
| 01.49
+
| 01:49
| Comments are used to understand the flow of program
+
| Comments are used to understand the flow of program.
  
 
|-
 
|-
| 01.52
+
| 01:52
| It is useful for documentation
+
| It is useful for documentation.
  
 
|-
 
|-
| 01.55
+
| 01:55
| It gives us information about the program
+
| It gives us information about the program.
  
 
|-
 
|-
| 01.59
+
| 01:59
 
| The double slash is called as single line comment. Now press Enter.
 
| The double slash is called as single line comment. Now press Enter.
  
 
|-
 
|-
| 02.05
+
| 02:05
| Type hash '''“#include”''' space opening angle bracket ''' ''closing angle bracket ''' .
+
| Type (hash) '''“#include”''', space, opening angle bracket, closing angle bracket .
 
+
  
 
|-
 
|-
| 02.13
+
| 02:13
|It is  a good practice to complete the brackets first, and then start writing inside it  
+
| It is  a good practice to complete the brackets first, and then start writing inside it.
  
 
|-
 
|-
| 02.20
+
| 02:20
 
| Now Inside the bracket, type '''“iostream”''' .
 
| Now Inside the bracket, type '''“iostream”''' .
  
 
|-
 
|-
| 02.23
+
| 02:23
| Here '''iostream''' is a '''header file'''  
+
| Here '''iostream''' is a '''header file'''.
  
 
|-
 
|-
| 02.26
+
| 02:26
| This file includes the declaration of  standard input output functions  in C++.Now press Enter
+
| This file includes the declaration of  standard input output functions  in '''C++.''' Now press '''Enter'''.
  
 
|-
 
|-
| 02.35
+
| 02:35
| Type '''“using”''' space '''“namespace”''' space '''“std”''' and a semicolon '''“;”''' .
+
| Type '''“using”''' space '''“namespace”''' space '''“std”''' and a semicolon '''“;”''' .
  
 
|-
 
|-
|02.45
+
| 02:45
| The '''using''' statement informs the compiler that you want to use the '''std namespace'''
+
| The '''using''' statement informs the compiler that you want to use the '''std namespace'''.
  
 
|-
 
|-
| 02.52
+
| 02:52
| The purpose of '''namespace''' is to avoid name collisions  
+
| The purpose of '''namespace''' is to avoid name collisions.
  
 
|-
 
|-
| 02.56
+
| 02:56
| It is done by localizing the names of identifiers
+
| It is done by localizing the names of identifiers.
  
 
|-
 
|-
|03.00
+
| 03:00
| It creates a declarative region and defines a scope
+
| It creates a declarative region and defines a scope.
  
 
|-
 
|-
| 03.05
+
| 03:05
| Anything defined within a '''namespace''' is in the SCOPE of that namespace
+
| Anything defined within a '''namespace''' is in the SCOPE of that namespace.
  
 
|-
 
|-
| 03.11
+
| 03:11
|Here '''std''' is the '''namespace''' in which entire standard C++ library is declared. Now press '''Enter'''.
+
| Here '''std''' is the '''namespace''' in which entire standard C++ library is declared. Now press '''Enter'''.
 
+
  
 
|-  
 
|-  
| 03.20
+
| 03:20
 
| Type '''“int”''' space '''“main”''' opening bracket, closing bracket .
 
| Type '''“int”''' space '''“main”''' opening bracket, closing bracket .
 
  
 
|-
 
|-
| 03.26
+
| 03:26
| '''main''' is a special '''function'''   
+
| '''main''' is a special '''function'''.  
  
 
|-
 
|-
| 03.30
+
| 03:30
 
| It denotes that the execution of the program begins from this line.
 
| It denotes that the execution of the program begins from this line.
  
 
|-
 
|-
| 03.34
+
| 03:34
|The opening and the closing bracket is called as'' Parenthesis''.
+
| The opening and the closing bracket is called as'' Parenthesis''.
 +
 
 
|-
 
|-
| 03.39
+
| 03:39
 
| Parenthesis followed by '''main'''  tells the user that '''main''' is a '''function.'''
 
| Parenthesis followed by '''main'''  tells the user that '''main''' is a '''function.'''
  
 
|-
 
|-
| 03.45
+
| 03:45
| Here the '''int''' '''main''' '''function''' takes no '''arguments''' and returns a value of type integer.
+
| Here, the '''int''' '''main()''' function takes no '''arguments''' and returns a value of type integer.
  
 
|-
 
|-
| 03.52
+
| 03:52
| We will learn about data types in another tutorial.
+
| We will learn about data types in another tutorial.
  
 
|-
 
|-
| 03.56
+
| 03:56
|Now  let us switch to the slides to know more about  main function.
+
| Now  let us switch to the slides to know more about  main function.
  
 
|-
 
|-
| 04.02
+
| 04:02
| Every '''program'''should have  one main function
+
| Every '''program''' should have  one main function.
  
 
|-
 
|-
| 04.04
+
| 04:04
| There should NOT be more than one “main” function
+
| There should NOT be more than one “main” function.
  
 
|-
 
|-
| 04.09
+
| 04:09
| Otherwise the compiler cannot locate the beginning of the program  
+
| Otherwise the compiler cannot locate the beginning of the program.
  
 
|-
 
|-
| 04.13
+
| 04:13
| The empty pair of parentheses indicates that main has no '''arguments'''
+
| The empty pair of parentheses indicates that main has no '''arguments'''.
  
 
|-
 
|-
| 04.19
+
| 04:19
 
| The concept of '''arguments''' will be discussed in  the upcoming tutorials.  
 
| The concept of '''arguments''' will be discussed in  the upcoming tutorials.  
  
 
|-
 
|-
| 04.24
+
| 04:24
| Now come back to our program. Press enter.
+
| Now come back to our program. Press Enter.
  
 
|-
 
|-
| 04.29
+
| 04:29
| Type opening curly bracket '''“{”'''
+
| Type opening curly bracket '''“{”'''.
  
 
|-
 
|-
| 04.32
+
| 04:32
| The opening  curly  bracket marks the beginning of the '''function main. '''
+
| The opening  curly  bracket marks the beginning of the function '''main()'''.
  
 
|-
 
|-
| 04.37
+
| 04:37
|Then Type closing curly bracket '''“}”'''
+
| Then Type closing curly bracket '''“}”'''.
  
 
|-
 
|-
| 04.40
+
| 04:40
| The closing bracket indicates the end of the '''function main '''
+
| The closing bracket indicates the end of the function '''main()'''.
  
 
|-
 
|-
| 04.45
+
| 04:45
|Now Inside the bracket press enter twice
+
| Now, inside the bracket press enter twice.
  
 
|-
 
|-
| 04.49
+
| 04:49
 
| Move the cursor one line up.
 
| Move the cursor one line up.
  
 
|-
 
|-
|04.51
+
| 04:51
| Indentation makes the code easier to read
+
| Indentation makes the code easier to read.
  
 
|-
 
|-
| 04.54
+
| 04:54
| It also helps to locate errors faster
+
| It also helps to locate errors faster.
  
 
|-
 
|-
| 04.58
+
| 04:58
|So let us  give a  space here.
+
| So let us  give a  space here.
  
 
|-
 
|-
| 05.01
+
| 05:01
|And type '''“cout”''' space two opening angle bracket ''''
+
| And type '''“cout”''' space two opening angle bracket ''''.
  
 
|-
 
|-
| 05.07
+
| 05:07
 
| Here '''cout '''is a standard '''C++ function''' to print the output on the terminal.
 
| Here '''cout '''is a standard '''C++ function''' to print the output on the terminal.
 
 
  
 
|-
 
|-
| 05.14
+
| 05:14
|Now  after the brackets, type within  double quotes '''
+
| Now  after the brackets, type within  double quotes.
  
 
|-
 
|-
| 05.18
+
| 05:18
|Anything within the double quotes in the '''cout ''' functions will be printed.  
+
| Anything within the double quotes, in the '''cout ''' functions, will be printed.  
  
 
|-
 
|-
| 05.24
+
| 05:24
|Now inside a quote type“Talk to a teacher backslash \n”'''.   
+
| Now inside a quote type“Talk to a teacher backslash n” (\n)'''.   
  
 
|-
 
|-
| 05.31
+
| 05:31
| Here '''\n''' signifies newline
+
| Here '''\n''' signifies newline.
  
 
|-
 
|-
| 05.35
+
| 05:35
| As a result, after execution of the '''cout function''', the cursor moves to the new line.
+
| As a result, after execution of the '''cout''' function, the cursor moves to the new line.
  
 
|-
 
|-
| 05.41
+
| 05:41
| Every C++ statement must end with a '''semicolon'''  
+
| Every C++ statement must end with a '''semicolon'''.
 
+
  
 
|-
 
|-
| 05.45
+
| 05:45
 
| Hence type it at the end of this line.
 
| Hence type it at the end of this line.
  
 
|-
 
|-
| 05.48
+
| 05:48
| Semicolon acts as a statement terminator. Now press Enter.
+
| Semicolon acts as a statement terminator. Now press '''Enter.'''
  
 
|-
 
|-
| 05.53
+
| 05:53
 
| Give a space here and  Type '''“return”''' space '''“0”''' and a semicolon '''“;”.'''
 
| Give a space here and  Type '''“return”''' space '''“0”''' and a semicolon '''“;”.'''
  
 
|-
 
|-
| 06.00
+
| 06:00
| This statement returns the integer zero
+
| This statement returns the integer zero.
 
+
  
 
|-
 
|-
| 06.03
+
| 06:03
| An integer has to be returned for this '''function''' because the '''function''' type is '''int'''
+
| An integer has to be returned for this '''function''' because the '''function''' type is '''int'''.
 
+
  
 
|-
 
|-
| 06.10
+
| 06:10
| The '''return''' statement marks the end of executable statements
+
| The '''return''' statement marks the end of executable statements.
 
+
  
 
|-
 
|-
| 06.14
+
| 06:14
 
| We will learn more about the returned values in another tutorial.
 
| We will learn more about the returned values in another tutorial.
  
 
|-
 
|-
| 06.20
+
| 06:20
| Now click on '''“Save”''' button to save the file  
+
| Now click on '''“Save”''' button to save the file.
 
+
  
 
|-
 
|-
| 06.23
+
| 06:23
| It is a good habit to save files frequently
+
| It is a good habit to save files frequently.
 
+
  
 
|-
 
|-
| 06.26
+
| 06:26
| This will protect you from sudden power failures
+
| This will protect you from sudden power failures.
 
+
  
 
|-
 
|-
| 06.30
+
| 06:30
 
| It will also be useful in case the applications were to crash.
 
| It will also be useful in case the applications were to crash.
  
 
|-
 
|-
| 06.34
+
| 06:34
 
| Let us now compile the program.
 
| Let us now compile the program.
  
 
|-
 
|-
| 06.36
+
| 06:36
| Come back to a terminal
+
| Come back to our terminal.
 
+
  
 
|-
 
|-
| 06.39
+
| 06:39
 
| Type '''“g++”''' space '''“talk.cpp”''' space hyphen '''“-o”''' space '''“output”.'''
 
| Type '''“g++”''' space '''“talk.cpp”''' space hyphen '''“-o”''' space '''“output”.'''
  
 
|-
 
|-
| 06.49
+
| 06:49
|Here '''g++''' is the compiler used to compile '''C++ '''programs
+
| Here '''g++''' is the compiler used to compile '''C++ '''programs.
 
+
  
 
|-
 
|-
| 06.55
+
| 06:55
| '''talk.cpp''' is our filename  
+
| '''talk.cpp''' is our filename.
  
 
|-
 
|-
| 06.59
+
| 06:59
| '''hyphen -o output''' says that the executable should go to the file output.  
+
| '''hyphen -o output''' says that the executable should go to the file "output".  
  
 
|-
 
|-
| 07.05
+
| 07:05
| 'Now press enter
+
| Now press '''Enter'''.
  
 
|-
 
|-
| 07.07
+
| 07:07
| We see that the program is compiled.
+
| We see that the program is compiled.
  
 
|-
 
|-
| 07.10
+
| 07:10
| By typing '''ls space hyphen -lrt''', we can see that '''output''' is the last file to be created.
+
| By typing '''ls space hyphen lrt''', we can see that '''output''' is the last file to be created.
  
 
|-
 
|-
| 07.19
+
| 07:19
 
| Let us  execute a  program,  type  '''“./output” '''(dot slash output).
 
| Let us  execute a  program,  type  '''“./output” '''(dot slash output).
 
  
 
|-
 
|-
| 07.24
+
| 07:24
|And  Press '''Enter.'''
+
| And  Press '''Enter.'''
  
 
|-
 
|-
| 07.27
+
| 07:27
 
| Here the output is displayed as '''“Talk to a teacher”.'''
 
| Here the output is displayed as '''“Talk to a teacher”.'''
  
 
|-
 
|-
| 07.30
+
| 07:30
| Now let us see the common errors which we can come across
+
| Now let us see the common errors which we can come across.
 
+
  
 
|-
 
|-
| 07.35   
+
| 07:35   
| switch back to  a editor.
+
| Switch back to  our text editor.
  
 
|-
 
|-
| 07.38
+
| 07:38
 
| Suppose here we miss the '''}'''(closing curly bracket)
 
| Suppose here we miss the '''}'''(closing curly bracket)
 +
 
|-
 
|-
| 07.42
+
| 07:42
|Now  save the file.
+
| now save the file.
  
 
|-
 
|-
| 07.44
+
| 07:44
| Let us execute. Come back to a terminal
+
| Let us execute. Come back to our terminal.
  
 
|-
 
|-
| 07.48
+
| 07:48
| Now compile and run the program using the command we used before. We see an error
+
| Now compile and run the program using the command we used before. We see an error.
  
 
|-
 
|-
| 07.55
+
| 07:55
| We see that there is an error at line no.7 in our '''talk.cpp''' file  that Expected curly bracket at the end of input.
+
| We see that there is an error at line no.7 in our '''talk.cpp''' file  that "expected curly bracket at the end of input".
 
+
  
 
|-
 
|-
| 08.07
+
| 08:07
|Now  Come back to our  text editor .
+
| Now  Come back to our  text editor .
  
 
|-
 
|-
| 08.09
+
| 08:09
| As i said before the closing curly bracket marks the end of the function main
+
| As I said before, the closing curly bracket marks the end of the function main
 
+
  
 
|-
 
|-
| 08.14
+
| 08:14
 
| Hence re-insert the bracket here. Now Save the file.
 
| Hence re-insert the bracket here. Now Save the file.
 
  
 
|-
 
|-
| 08.19
+
| 08:19
| Let us execute it again
+
| Let us execute it again.
 
+
  
 
|-
 
|-
| 08.21
+
| 08:21
| You can recall the previously entered commands by using up arrow key  
+
| You can recall the previously entered commands by using up arrow key.
 
+
  
 
|-
 
|-
| 08.26
+
| 08:26
 
| That is what I did now.
 
| That is what I did now.
  
 
|-
 
|-
| 08.30
+
| 08:30
| Yes it is working.
+
| Yes, it is working.
 
+
  
 
|-
 
|-
|08.32
+
| 08:32
| I will show you another common error
+
| I will show you another common error.
 
+
  
 
|-
 
|-
| 08.35
+
| 08:35
 
| Let us switch back to our text editor.
 
| Let us switch back to our text editor.
  
 
|-
 
|-
| 08.37
+
| 08:37
 
| Now, suppose here we missed '''std.'''
 
| Now, suppose here we missed '''std.'''
  
 
|-
 
|-
| 08.41
+
| 08:41
| Let us save the file  
+
| Let us save the file.
 
+
  
 
|-
 
|-
| 08.44
+
| 08:44
| Come back to our  terminal .  
+
| Come back to our  terminal .  
  
 
|-
 
|-
| 08.46
+
| 08:46
 
| Let us compile .
 
| Let us compile .
  
 
|-
 
|-
| 08.48
+
| 08:48
| We see that there is an  errors at line no 3 and  line no 6 in our '''talk.cpp''' file
+
| We see that there is an  error at line no.3 and  line no.6 in our '''talk.cpp''' file.
 
+
  
 
|-
 
|-
| 08.56
+
| 08:56
| That expected identifier before '''semicolon''' and '''cout''' was not declared in this scope.
+
| That "expected identifier before 'semicolon' " and " 'cout' was not declared in this scope".
  
 
|-
 
|-
|09.05
+
| 09:05
| As '''cout''' is the standard '''C++ library function'''
+
| As '''cout''' is the standard '''C++ library function'''.
 
+
  
 
|-
 
|-
| 09.09
+
| 09:09
| and the entire '''C++ library function''' is defined under '''std namespace '''
+
| and the entire '''C++ library function''' is defined under '''std namespace '''.
 
+
  
 
|-
 
|-
| 09.15
+
| 09:15
 
| Hence it is giving an error.
 
| Hence it is giving an error.
  
 
|-
 
|-
| 09.18
+
| 09:18
| Let us now  fix the error
+
| Let us now  fix the error.Come back to our Text editor.  Type '''std''' here.
  
 
|-
 
| 09.19
 
| Come back to our Text editor.  Type '''std''' here
 
 
|-
 
|-
| 09.23
+
| 09:23
| Let us Save it.
+
| Let us save it.
  
 
|-
 
|-
| 09.25
+
| 09:25
| Let us compile it again.
+
| Let us compile it again.
  
 
|-
 
|-
| 09.29
+
| 09:29
| Yes it is working.
+
| Yes, it is working.As an assignment,
 
+
  
 
|-
 
|-
| 09.32
+
| 09:33
| As an assignment,
+
| write a program to print your name and city.
 
+
  
 
|-
 
|-
| 09.33
+
| 09:37
| Write a program to print your name and city
+
| We used '''single line comment''' in this tutorial.
 
+
  
 
|-
 
|-
| 09.37
+
| 09:40
| We used '''single line comment''' in this tutorial
+
| Now just try to give a '''multiline comment'''.
 
+
  
 
|-
 
|-
|09.40
+
| 09:44
| Now just try to give a '''multiline comment'''
+
| Watch the video available at the link shown below.  
 
+
 
+
   
+
  
 
|-
 
|-
| 09.44
+
| 09:46
| Watch the video available at the link shown below 
+
| It summarizes the Spoken Tutorial project.
 
+
|-
+
| 09.46
+
| It summarises the Spoken Tutorial project  
+
 
+
  
 
|-
 
|-
| 09.48
+
| 09:48
 
| 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.
  
 
|-
 
|-
|09.53
+
| 09:53
|The Spoken Tutorial Project Team  
+
| The Spoken Tutorial Project Team:
 
+
  
 
|-
 
|-
| 09.55
+
| 09:55
| Conducts workshops using spoken tutorials  
+
| Conducts workshops using spoken tutorials.
 
+
  
 
|-
 
|-
|09.58
+
| 09:58
| Gives certificates to those who pass an online test  
+
| Gives certificates to those who pass an online test.
 
+
  
 
|-
 
|-
| 10.01
+
| 10:01
 
| For more details, please  write to  contact @spoken-tutorial.org
 
| For more details, please  write to  contact @spoken-tutorial.org
  
 
|-
 
|-
|10.10
+
| 10:10
| 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.
  
 
|-
 
|-
| 10.14
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| 10:14
| It is supported by the National Mission on Education through ICT, MHRD, Government of India
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| It is supported by the National Mission on Education through ICT, MHRD, Government of India.
 
+
  
 
|-
 
|-
| 10.20
+
| 10:20
| More information on this Mission is available at the link shown below
+
| More information on this Mission is available at the link shown below.
  
 
|-
 
|-
| 10.25
+
| 10:25
| This is Ashwini Patil from IIT Bombay signing off
+
| This is Ashwini Patil from IIT Bombay signing off.
 
+
  
 
|-
 
|-
| 10.28
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| 10:28
| Thank you for watching
+
| Thank you for watching.
  
 
|}
 
|}

Latest revision as of 16:02, 22 March 2017

Time Narration
00:02 Welcome to the spoken tutorial on First C++ program.
00:07 In this tutorial I am going to explain,
00:10 How to write a C++ program
00:13 How to compile it, How to execute it
00:17 We will also explain some common errors and their solution.
00:22 To record this tutorial, I am using Ubuntu operating system version 11.10 and
00:29 G++ Compiler version 4.5.2 on Ubuntu.
00:35 To practice this tutorial,
00:37 You should be familiar with Ubuntu Operating System and an Editor
00:44 Some editors are 'vim' and 'gedit'.
00:48 I am using 'gedit' in this tutorial.
00:50 For relevant tutorial please visit our website which is as shown.
00:56 Let me tell you how to write a C++ program through an example.
01:01 Open the terminal Window using Ctrl, Alt and T keys simultaneously on your keyboard.
01:09 To open the text editor, type on the terminal.
01:13 “gedit” space “talk” dot “.cpp” space ampersand “&” sign.
01:21 We use the “&” to free up the prompt.
01:25 Please note that all the C++ files will have the extension “.cpp”.
01:31 Now Press Enter,
01:33 the text editor has opened.
01:35 Let us start to write a program.
01:38 Type double slash “//” space “My first C++ program”.
01:44 Here, double slash is used to comment the line.
01:49 Comments are used to understand the flow of program.
01:52 It is useful for documentation.
01:55 It gives us information about the program.
01:59 The double slash is called as single line comment. Now press Enter.
02:05 Type (hash) “#include”, space, opening angle bracket, closing angle bracket .
02:13 It is a good practice to complete the brackets first, and then start writing inside it.
02:20 Now Inside the bracket, type “iostream” .
02:23 Here iostream is a header file.
02:26 This file includes the declaration of standard input output functions in C++. Now press Enter.
02:35 Type “using” space “namespace” space “std” and a semicolon “;” .
02:45 The using statement informs the compiler that you want to use the std namespace.
02:52 The purpose of namespace is to avoid name collisions.
02:56 It is done by localizing the names of identifiers.
03:00 It creates a declarative region and defines a scope.
03:05 Anything defined within a namespace is in the SCOPE of that namespace.
03:11 Here std is the namespace in which entire standard C++ library is declared. Now press Enter.
03:20 Type “int” space “main” opening bracket, closing bracket .
03:26 main is a special function.
03:30 It denotes that the execution of the program begins from this line.
03:34 The opening and the closing bracket is called as Parenthesis.
03:39 Parenthesis followed by main tells the user that main is a function.
03:45 Here, the int main() function takes no arguments and returns a value of type integer.
03:52 We will learn about data types in another tutorial.
03:56 Now let us switch to the slides to know more about main function.
04:02 Every program should have one main function.
04:04 There should NOT be more than one “main” function.
04:09 Otherwise the compiler cannot locate the beginning of the program.
04:13 The empty pair of parentheses indicates that main has no arguments.
04:19 The concept of arguments will be discussed in the upcoming tutorials.
04:24 Now come back to our program. Press Enter.
04:29 Type opening curly bracket “{”.
04:32 The opening curly bracket marks the beginning of the function main().
04:37 Then Type closing curly bracket “}”.
04:40 The closing bracket indicates the end of the function main().
04:45 Now, inside the bracket press enter twice.
04:49 Move the cursor one line up.
04:51 Indentation makes the code easier to read.
04:54 It also helps to locate errors faster.
04:58 So let us give a space here.
05:01 And type “cout” space two opening angle bracket '.
05:07 Here cout is a standard C++ function to print the output on the terminal.
05:14 Now after the brackets, type within double quotes.
05:18 Anything within the double quotes, in the cout functions, will be printed.
05:24 Now inside a quote type“Talk to a teacher backslash n” (\n).
05:31 Here \n signifies newline.
05:35 As a result, after execution of the cout function, the cursor moves to the new line.
05:41 Every C++ statement must end with a semicolon.
05:45 Hence type it at the end of this line.
05:48 Semicolon acts as a statement terminator. Now press Enter.
05:53 Give a space here and Type “return” space “0” and a semicolon “;”.
06:00 This statement returns the integer zero.
06:03 An integer has to be returned for this function because the function type is int.
06:10 The return statement marks the end of executable statements.
06:14 We will learn more about the returned values in another tutorial.
06:20 Now click on “Save” button to save the file.
06:23 It is a good habit to save files frequently.
06:26 This will protect you from sudden power failures.
06:30 It will also be useful in case the applications were to crash.
06:34 Let us now compile the program.
06:36 Come back to our terminal.
06:39 Type “g++” space “talk.cpp” space hyphen “-o” space “output”.
06:49 Here g++ is the compiler used to compile C++ programs.
06:55 talk.cpp is our filename.
06:59 hyphen -o output says that the executable should go to the file "output".
07:05 Now press Enter.
07:07 We see that the program is compiled.
07:10 By typing ls space hyphen lrt, we can see that output is the last file to be created.
07:19 Let us execute a program, type “./output” (dot slash output).
07:24 And Press Enter.
07:27 Here the output is displayed as “Talk to a teacher”.
07:30 Now let us see the common errors which we can come across.
07:35 Switch back to our text editor.
07:38 Suppose here we miss the }(closing curly bracket)
07:42 now save the file.
07:44 Let us execute. Come back to our terminal.
07:48 Now compile and run the program using the command we used before. We see an error.
07:55 We see that there is an error at line no.7 in our talk.cpp file that "expected curly bracket at the end of input".
08:07 Now Come back to our text editor .
08:09 As I said before, the closing curly bracket marks the end of the function main
08:14 Hence re-insert the bracket here. Now Save the file.
08:19 Let us execute it again.
08:21 You can recall the previously entered commands by using up arrow key.
08:26 That is what I did now.
08:30 Yes, it is working.
08:32 I will show you another common error.
08:35 Let us switch back to our text editor.
08:37 Now, suppose here we missed std.
08:41 Let us save the file.
08:44 Come back to our terminal .
08:46 Let us compile .
08:48 We see that there is an error at line no.3 and line no.6 in our talk.cpp file.
08:56 That "expected identifier before 'semicolon' " and " 'cout' was not declared in this scope".
09:05 As cout is the standard C++ library function.
09:09 and the entire C++ library function is defined under std namespace .
09:15 Hence it is giving an error.
09:18 Let us now fix the error.Come back to our Text editor. Type std here.
09:23 Let us save it.
09:25 Let us compile it again.
09:29 Yes, it is working.As an assignment,
09:33 write a program to print your name and city.
09:37 We used single line comment in this tutorial.
09:40 Now just try to give a multiline comment.
09:44 Watch the video available at the link shown below.
09:46 It summarizes the Spoken Tutorial project.
09:48 If you do not have good bandwidth, you can download and watch it.
09:53 The Spoken Tutorial Project Team:
09:55 Conducts workshops using spoken tutorials.
09:58 Gives certificates to those who pass an online test.
10:01 For more details, please write to contact @spoken-tutorial.org
10:10 Spoken Tutorial Project is a part of the Talk to a Teacher project.
10:14 It is supported by the National Mission on Education through ICT, MHRD, Government of India.
10:20 More information on this Mission is available at the link shown below.
10:25 This is Ashwini Patil from IIT Bombay signing off.
10:28 Thank you for watching.

Contributors and Content Editors

Ashwini, Devraj, PoojaMoolya, Pratik kamble, Sandhya.np14, Sneha