Difference between revisions of "C-and-C++/C2/First-C++-Program/English-timed"
From Script | Spoken-Tutorial
PoojaMoolya (Talk | contribs) |
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− | | To record this tutorial, I am using Ubuntu operating system version 11.10 and G++ Compiler version 4.5.2 on Ubuntu. | + | | To record this tutorial, I am using Ubuntu operating system version 11.10 and |
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+ | | 00.29 | ||
+ | | G++ Compiler version 4.5.2 on Ubuntu. | ||
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− | | 00. | + | | 00.37 |
| You should be familiar with Ubuntu Operating System and an Editor | | You should be familiar with Ubuntu Operating System and an Editor | ||
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− | | 00. | + | | 00.50 |
− | | For relevant tutorial Please visit our website | + | | For relevant tutorial Please visit our website which is as shown |
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| 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. |
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| 01.09 | | 01.09 | ||
− | | To open the text editor, type | + | | To open the text editor, type on the terminal. |
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| 01.13 | | 01.13 | ||
− | | '''“gedit”''' space '''“talk”''' dot '''“.cpp”''' space ampersand '''“&” | + | | '''“gedit”''' space '''“talk”''' dot '''“.cpp”''' space ampersand '''“&”''' sign. |
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− | | 01. | + | | 01.35 |
| Let us start to write a program. | | Let us start to write a program. | ||
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| 01.38 | | 01.38 | ||
− | | Type double slash '''“//”''' space | + | | Type double slash '''“//”''' space '''“My first C++ program”.''' |
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| 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. |
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− | |03. | + | |03.00 |
| It creates a declarative region and defines a scope | | It creates a declarative region and defines a scope | ||
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| 03.20 | | 03.20 | ||
− | | Type '''“int”''' space '''“main”''' opening bracket | + | | Type '''“int”''' space '''“main”''' opening bracket, closing bracket . |
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− | | 03. | + | | 03.26 |
| '''main''' is a special '''function''' | | '''main''' is a special '''function''' | ||
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− | | 03. | + | | 03.34 |
|The opening and the closing bracket is called as'' Parenthesis''. | |The opening and the closing bracket is called as'' Parenthesis''. | ||
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| 03.56 | | 03.56 | ||
− | |Now | + | |Now let us switch to the slides to know more about main function. |
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− | | 04. | + | | 04.04 |
| There should NOT be more than one “main” function | | There should NOT be more than one “main” function | ||
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| 04.19 | | 04.19 | ||
− | | The concept of '''arguments''' will be discussed in the upcoming tutorials. Now come back to our program. | + | | The concept of '''arguments''' will be discussed in the upcoming tutorials. |
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+ | | 04.24 | ||
+ | | Now come back to our program. Press enter. | ||
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− | | 04. | + | | 04.54 |
| It also helps to locate errors faster | | It also helps to locate errors faster | ||
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− | | 05. | + | | 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. | ||
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| 05.18 | | 05.18 | ||
− | |Anything within the double quotes in the '''cout ''' functions will be printed. Now inside a quote type“Talk to a teacher backslash \n”'''. | + | |Anything within the double quotes in the '''cout ''' functions will be printed. |
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+ | | 05.24 | ||
+ | |Now inside a quote type“Talk to a teacher backslash \n”'''. | ||
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| 06.03 | | 06.03 | ||
− | | An integer has to be returned for this '''function''' | + | | An integer has to be returned for this '''function''' because the '''function''' type is '''int''' |
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− | | 06. | + | | 06.14 |
| We will learn more about the returned values in another tutorial. | | We will learn more about the returned values in another tutorial. | ||
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− | | 06. | + | | 06.36 |
| Come back to a terminal | | Come back to a terminal | ||
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| 06.59 | | 06.59 | ||
− | | '''-o output''' says that the executable should go to the file output. Now press enter | + | | '''hyphen -o output''' says that the executable should go to the file output. |
+ | |||
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+ | | 07.05 | ||
+ | | 'Now press enter | ||
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| 07.10 | | 07.10 | ||
− | | By typing '''ls -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. |
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− | | 07. | + | | 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 | ||
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| 07.44 | | 07.44 | ||
− | | Let us execute.Come back to a terminal | + | | Let us execute. Come back to a terminal |
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| 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 |
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| 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. |
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| 08.14 | | 08.14 | ||
− | | Hence re-insert the bracket here. | + | | Hence re-insert the bracket here. Now Save the file. |
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| 08.26 | | 08.26 | ||
− | | That is what I did now. Yes it is working. | + | | That is what I did now. |
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+ | |- | ||
+ | | 08.30 | ||
+ | | Yes it is working. | ||
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− | | 08. | + | | 08.37 |
− | | Now, suppose here we missed '''std.''' | + | | Now, suppose here we missed '''std.''' |
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− | | 08. | + | | 08.41 |
− | | | + | | Let us save the file |
+ | |- | ||
+ | | 08.44 | ||
+ | | Come back to our terminal . | ||
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+ | |- | ||
+ | | 08.46 | ||
+ | | Let us compile . | ||
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| 09.19 | | 09.19 | ||
− | | Come back to our Text editor | + | | Come back to our Text editor. Type '''std''' here |
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| 09.23 | | 09.23 | ||
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| 09.25 | | 09.25 | ||
− | | Let us compile it again.Yes it is working. | + | | Let us compile it again. |
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+ | |- | ||
+ | | 09.29 | ||
+ | | Yes it is working. | ||
+ | |||
+ | |||
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| 09.32 | | 09.32 | ||
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| 09.44 | | 09.44 | ||
− | | Watch the video available at the link shown | + | | Watch the video available at the link shown below |
− | + | ||
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− | | 09. | + | | 09.46 |
| It summarises the Spoken Tutorial project | | It summarises the Spoken Tutorial project | ||
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− | | 09. | + | | 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. | ||
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| 10.20 | | 10.20 | ||
− | | More information on this Mission is available at | + | | More information on this Mission is available at the link shown below |
|- | |- |
Revision as of 14:55, 30 January 2014
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 |
00.14 | 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 programshould 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”. |
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 a 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 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 a editor. |
07.38 | Suppose here we miss the {. |
07.42 | Now save the file. |
07.44 | Let us execute. Come back to a 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 errors 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
|
09.19 | 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.
|
09.32 | 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 summarises 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