Difference between revisions of "C-and-C++/C2/Logical-Operators/English-timed"
From Script | Spoken-Tutorial
(Created page with '{| border=1 || ''Time''' || '''Narration''' |- | 00.02 | Welcome to the spoken tutorial on '''Logical operators in C and C++.''' |- | 00.08 |In this tutorial we will learn abou…') |
PoojaMoolya (Talk | contribs) |
||
| Line 9: | Line 9: | ||
|- | |- | ||
| 00.08 | | 00.08 | ||
| − | |In this tutorial we will learn about:Logical operators like | + | |In this tutorial we will learn about:Logical operators like Logical AND eg. expression1 && expression2 |
|- | |- | ||
| − | | 00. | + | | 00.16 |
| Logical OR | | Logical OR | ||
| − | eg. expression1 | + | eg. expression1 or expression2 |
|- | |- | ||
| 00.21 | | 00.21 | ||
| − | | | + | |Logical NOT |
| − | eg. | + | eg. not (Expression1) |
|- | |- | ||
| Line 32: | Line 32: | ||
|- | |- | ||
| − | |00. | + | |00.33 |
|'''gcc''' and '''g++ Compiler '''version '''4.6.1 on''' '''Ubuntu.''' | |'''gcc''' and '''g++ Compiler '''version '''4.6.1 on''' '''Ubuntu.''' | ||
|- | |- | ||
| − | | 00. | + | | 00.39 |
| Let us start with the introduction to the '''logical operators'''. | | Let us start with the introduction to the '''logical operators'''. | ||
|- | |- | ||
| − | | 00. | + | | 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. | + | | 00.48 |
|non zero means true | |non zero means true | ||
|- | |- | ||
| − | | 00. | + | | 00.50 |
| − | | | + | |And zero means false |
| Line 57: | Line 57: | ||
|- | |- | ||
| − | | 00. | + | | 00.58 |
| Now I'll explain the logical operators with the help of an example. | | Now I'll explain the logical operators with the help of an example. | ||
|- | |- | ||
| − | | 01. | + | | 01.03 |
| Here is the program for '''logical operators''' in '''C'''. | | Here is the program for '''logical operators''' in '''C'''. | ||
|- | |- | ||
| − | | 01. | + | | 01.08 |
| Inside the main block | | Inside the main block | ||
|- | |- | ||
| − | | 01. | + | | 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 77: | Line 77: | ||
|- | |- | ||
| − | |01. | + | |01.21 |
| − | | The '''scanf''' statement takes input from the user for | + | | The '''scanf''' statement takes input from the user for variables '''a''', '''b''' and''' c'''. |
|- | |- | ||
| Line 93: | Line 93: | ||
|- | |- | ||
| − | | 01. | + | | 01.43 |
|The expression is not evaluated further on encountering a false condition. | |The expression is not evaluated further on encountering a false condition. | ||
| Line 101: | Line 101: | ||
|- | |- | ||
| − | | 01. | + | | 01.56 |
|If a is less than b, then the expression won't be evaluated further. | |If a is less than b, then the expression won't be evaluated further. | ||
|- | |- | ||
| − | | 02. | + | | 02.02 |
|This statement is evaluated if the previous condition is true. | |This statement is evaluated if the previous condition is true. | ||
| Line 117: | Line 117: | ||
|- | |- | ||
| − | | 02. | + | | 02.16 |
| Otherwise '''c is greatest '''is displayed on the screen. | | Otherwise '''c is greatest '''is displayed on the screen. | ||
| Line 129: | Line 129: | ||
|- | |- | ||
| − | | 02. | + | | 02.30 |
|The expression is not evaluated further on encountering a true condition. | |The expression is not evaluated further on encountering a true condition. | ||
|- | |- | ||
| − | | 02. | + | | 02.35 |
|So, if '''a''' == zero, then the remaining two expressions won't be evaluated. | |So, if '''a''' == zero, then the remaining two expressions won't be evaluated. | ||
| Line 149: | Line 149: | ||
|- | |- | ||
| − | | 02. | + | | 02.57 |
|'''Save''' it with extension '''.c''' | |'''Save''' it with extension '''.c''' | ||
| Line 157: | Line 157: | ||
|- | |- | ||
| − | | 03. | + | | 03.03 |
| Open the terminal by pressing '''Ctrl, Alt and T '''keys simulataneously. | | Open the terminal by pressing '''Ctrl, Alt and T '''keys simulataneously. | ||
|- | |- | ||
| − | | 03. | + | | 03.08 |
| − | | To compile the code type '''gcc logical | + | | To compile the code type '''gcc space logical dot c space minus o space log''' Press enter |
|- | |- | ||
| Line 174: | Line 174: | ||
|- | |- | ||
| − | | 03. | + | | 03.29 |
|I will enter the values as, | |I will enter the values as, | ||
| Line 184: | Line 184: | ||
|- | |- | ||
| − | | 03. | + | | 03.39 |
|The output is displayed as, | |The output is displayed as, | ||
|- | |- | ||
| − | | 03. | + | | 03.42 |
|c is greatest. | |c is greatest. | ||
|- | |- | ||
| − | | 03. | + | | 03.45 |
|The product of a, b and c is zero. | |The product of a, b and c is zero. | ||
| Line 212: | Line 212: | ||
|- | |- | ||
| − | | 04. | + | | 04.06 |
| | Now to make the same program in C++, we make a few changes. | | | Now to make the same program in C++, we make a few changes. | ||
|- | |- | ||
| − | | 04. | + | | 04.11 |
|There's a change in the header file. | |There's a change in the header file. | ||
|- | |- | ||
| − | | 04. | + | | 04.14 |
|Using statement has been used. | |Using statement has been used. | ||
| Line 228: | Line 228: | ||
|- | |- | ||
| − | | 04. | + | | 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. | ||
|- | |- | ||
| − | | 04. | + | | 04.25 |
| Click on '''Save'''. | | Click on '''Save'''. | ||
| Line 245: | Line 245: | ||
|- | |- | ||
| − | |04. | + | |04.36 |
| − | |To compile the program type '''g++ logical.cpp | + | |To compile the program type '''g++ logical.cpp space minus o space log1'''. Press Enter |
|- | |- | ||
| Line 253: | Line 253: | ||
|- | |- | ||
| − | | 04. | + | | 04.53 |
|press '''Enter.''' | |press '''Enter.''' | ||
| Line 269: | Line 269: | ||
|- | |- | ||
| 05.02 | | 05.02 | ||
| − | |So | + | |So we see the output is similar to the C program. |
|- | |- | ||
| Line 280: | Line 280: | ||
|- | |- | ||
| − | | 05. | + | | 05.12 |
|Let's switch to the editor. | |Let's switch to the editor. | ||
| Line 296: | Line 296: | ||
|- | |- | ||
| − | | 05. | + | | 05.30 |
|Come back to the terminal | |Come back to the terminal | ||
|- | |- | ||
| − | | 05. | + | | 05.32 |
|Compile and execute as before | |Compile and execute as before | ||
| Line 312: | Line 312: | ||
|- | |- | ||
| − | | 05. | + | | 05.45 |
| This is because we have two different expressions here | | This is because we have two different expressions here | ||
|- | |- | ||
| − | | 05. | + | | 05.48 |
|We have to evaluate them as one expression using AND operator. | |We have to evaluate them as one expression using AND operator. | ||
| Line 324: | Line 324: | ||
|- | |- | ||
| − | | 05. | + | | 05.57 |
| Let us insert the brackets here and here. | | Let us insert the brackets here and here. | ||
| Line 332: | Line 332: | ||
|- | |- | ||
| − | | 06. | + | | 06.06 |
|Come back to the terminal. | |Come back to the terminal. | ||
|- | |- | ||
| 06.09 | | 06.09 | ||
| − | | | + | | Compile and execute as before |
|- | |- | ||
| Line 349: | Line 349: | ||
|- | |- | ||
| 06.24 | | 06.24 | ||
| − | | In this tutorial we learnt about | + | | In this tutorial we learnt about Logical AND eg. '''((a > b) && (a > c)) ''' |
| Line 360: | Line 360: | ||
|- | |- | ||
| − | | 06. | + | | 06.39 |
|Assignment | |Assignment | ||
| Line 368: | Line 368: | ||
|- | |- | ||
| − | | 06. | + | | 06.44 |
|Check whether the two numbers are equal or not using '''NOT''' operator. Hint: '''(a != b)''' | |Check whether the two numbers are equal or not using '''NOT''' operator. Hint: '''(a != b)''' | ||
| Line 390: | Line 390: | ||
|- | |- | ||
| − | | 07. | + | | 07.07 |
| Gives certificates for those who pass an online test | | Gives certificates for those who pass an online test | ||
Revision as of 15:30, 5 February 2014
| 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 eg. 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 |
| 03.00 | I have saved my file as logical.c |
| 03.03 | Open the terminal by pressing Ctrl, Alt and T keys simulataneously. |
| 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 |
| 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 |
| 04.31 | Open the terminal by pressing Ctrl, Alt and T keys simulataneously. |
| 04.36 | To compile the program type g++ logical.cpp space minus o space log1. Press Enter |
| 04.49 | to execute type ./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 summarises 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. |
