Difference between revisions of "C-and-C++/C2/Relational-Operators/English-timed"
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{| border=1 | {| border=1 | ||
− | + | |'''Time''' | |
− | + | |'''Narration''' | |
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− | + | ||
|- | |- | ||
− | |00 | + | |00:01 |
| Welcome to the spoken tutorial on '''Relational Operators''' in '''C''' and '''C++'''. | | Welcome to the spoken tutorial on '''Relational Operators''' in '''C''' and '''C++'''. | ||
|- | |- | ||
− | |00 | + | |00:06 |
| In this tutorial, we will learn about: | | In this tutorial, we will learn about: | ||
|- | |- | ||
− | |00 | + | |00:09 |
− | |Relational operators like | + | |Relational operators like, |
|- | |- | ||
− | |00 | + | |00:11 |
− | |Less than: | + | |Less than: e.g. a < b |
|- | |- | ||
− | |00 | + | |00:14 |
− | |Greater than: | + | |Greater than: e.g. a > b |
|- | |- | ||
− | |00 | + | |00:17 |
− | |Less than or equal to: | + | |Less than or equal to: e.g. a <= b |
|- | |- | ||
− | |00 | + | |00:22 |
− | |Greater than or equal to: | + | |Greater than or equal to: e.g. a >= b |
|- | |- | ||
− | |00 | + | |00:27 |
− | |Equal to: | + | |Equal to: e.g. a == b |
|- | |- | ||
− | |00 | + | |00:30 |
− | |Not equal to: | + | |Not equal to: e.g. a != b |
|- | |- | ||
− | | 00 | + | | 00:37 |
− | | | + | | To record this tutorial, I am using: '''Ubuntu 11.10''' as the operating system, |
|- | |- | ||
− | |00 | + | |00:42 |
|'''gcc''' and '''g++ Compiler '''version '''4.6.1 '''in '''Ubuntu.''' | |'''gcc''' and '''g++ Compiler '''version '''4.6.1 '''in '''Ubuntu.''' | ||
− | |||
|- | |- | ||
− | | 00 | + | | 00:50 |
| Let us begin with an introduction. | | Let us begin with an introduction. | ||
|- | |- | ||
− | |00 | + | |00:53 |
|Relational operators are used to compare integer and floating point numbers. | |Relational operators are used to compare integer and floating point numbers. | ||
|- | |- | ||
− | |00 | + | |00:57 |
− | |Expressions using relational operators '''return''' 0 for false and 1 for true. | + | |Expressions using relational operators '''return''' '''0''' for false and '''1''' for true. |
|- | |- | ||
− | | 01 | + | | 01:04 |
| Now I will demonstrate the relational operators with the help of a C program. | | Now I will demonstrate the relational operators with the help of a C program. | ||
|- | |- | ||
− | | 01 | + | | 01:09 |
| I have already made the program. | | I have already made the program. | ||
|- | |- | ||
− | |01 | + | |01:11 |
|So, I'll open the editor and explain the code. | |So, I'll open the editor and explain the code. | ||
|- | |- | ||
− | | 01 | + | | 01:15 |
| First, we declare two variables '''a '''and '''b'''. | | First, we declare two variables '''a '''and '''b'''. | ||
|- | |- | ||
− | | 01 | + | | 01:20 |
| This '''printf''' statement prompts the user to enter the values of a and b. | | This '''printf''' statement prompts the user to enter the values of a and b. | ||
|- | |- | ||
− | | 01 | + | | 01:26 |
| This '''scanf '''statement takes input for the variables '''a '''and '''b'''. | | This '''scanf '''statement takes input for the variables '''a '''and '''b'''. | ||
|- | |- | ||
− | | 01 | + | | 01:32 |
− | | Now we have the '''greater than''' operator. | + | | Now we have the '''greater than (>)''' operator. |
|- | |- | ||
− | |01 | + | |01:35 |
|This operator compares the two operands on either side of the operator. | |This operator compares the two operands on either side of the operator. | ||
|- | |- | ||
− | |01 | + | |01:38 |
− | |It | + | |It returns '''True''' if '''a''' is greater than '''b'''. |
|- | |- | ||
− | | 01 | + | | 01:43 |
| This '''printf '''statement is executed if the above condition is true. | | This '''printf '''statement is executed if the above condition is true. | ||
|- | |- | ||
− | |01 | + | |01:47 |
|If the above condition is '''false '''then it is skipped. | |If the above condition is '''false '''then it is skipped. | ||
|- | |- | ||
− | |01 | + | |01:50 |
|The control then jumps to the next statement. | |The control then jumps to the next statement. | ||
|- | |- | ||
− | | 01 | + | | 01:53 |
− | | We now have the '''less than''' operator. | + | | We now have the '''less than (<)''' operator. |
|- | |- | ||
− | |01 | + | |01:56 |
|This too compares the operands. | |This too compares the operands. | ||
|- | |- | ||
− | |01 | + | |01:57 |
− | |It | + | |It returns '''true''' when '''a''' is less than '''b'''. |
|- | |- | ||
− | | 02 | + | | 02:02 |
|This '''printf''' statement is executed if the above condition is '''true.''' | |This '''printf''' statement is executed if the above condition is '''true.''' | ||
|- | |- | ||
− | |02 | + | |02:06 |
|It is skipped otherwise. | |It is skipped otherwise. | ||
|- | |- | ||
− | |02 | + | |02:09 |
| Let's execute the code till here. | | Let's execute the code till here. | ||
|- | |- | ||
− | |02 | + | |02:13 |
− | |First comment out the following. | + | |First comment out the following. |
|- | |- | ||
− | | 02.24 | + | |02:16 |
+ | |Type '''/* (slash asterisk) | ||
+ | |||
+ | |- | ||
+ | |02:21 | ||
+ | | */ ''' (asterisk slash). | ||
+ | |||
+ | |- | ||
+ | | 02:24 | ||
| Click on '''Save'''. | | Click on '''Save'''. | ||
|- | |- | ||
− | |02 | + | |02:26 |
− | |I have saved my file as relational.c | + | |I have saved my file as '''relational.c'''. |
|- | |- | ||
− | | 02 | + | | 02:29 |
− | | Open the terminal window by pressing '''Ctrl, Alt | + | | Open the terminal window by pressing '''Ctrl, Alt''' and '''T '''keys simultaneously. |
|- | |- | ||
− | | 02 | + | | 02:35 |
− | | To compile, type the following on the terminal '''gcc relational | + | | To compile, type the following on the terminal '''gcc space relational dot c space -o space rel'''. |
|- | |- | ||
− | | 02 | + | | 02:49 |
| Press '''Enter'''. | | Press '''Enter'''. | ||
|- | |- | ||
− | | 02 | + | | 02:51 |
− | | To execute | + | | To execute, type '''./rel''' (dot slash rel). Press '''Enter'''. |
− | + | ||
|- | |- | ||
− | | 02 | + | | 02:56 |
| I enter '''a''' as 8 and '''b '''as 3. | | I enter '''a''' as 8 and '''b '''as 3. | ||
|- | |- | ||
− | | 03 | + | | 03:01 |
| The output is displayed: | | The output is displayed: | ||
|- | |- | ||
− | | 03 | + | | 03:03 |
− | | 8 is greater than 3. | + | | '''8 is greater than 3'''. |
|- | |- | ||
− | | 03 | + | | 03:07 |
| You can try executing this code with different values of '''a '''and '''b'''. | | You can try executing this code with different values of '''a '''and '''b'''. | ||
|- | |- | ||
− | |03 | + | |03:11 |
| Coming back to the code. | | Coming back to the code. | ||
|- | |- | ||
− | | 03 | + | | 03:14 |
− | | Delete the comment from here and put it | + | | Delete the comment from here |
+ | |- | ||
+ | | 03:18 | ||
+ | | and put it here. | ||
|- | |- | ||
− | | 03 | + | | 03:24 |
− | |Now we have the '''less than or equal to '''operator. | + | |Now we have the '''less than or equal to (<=) '''operator. |
|- | |- | ||
− | | 03 | + | | 03:28 |
| This operator compares the two operands on either side of the operator. | | This operator compares the two operands on either side of the operator. | ||
|- | |- | ||
− | | 03 | + | | 03:33 |
− | | It | + | | It returns '''true''' if '''a''' is less than or equal to '''b'''. |
|- | |- | ||
− | |03 | + | |03:38 |
| This '''printf '''statement is executed if the above condition is true. | | This '''printf '''statement is executed if the above condition is true. | ||
|- | |- | ||
− | | 03 | + | | 03:42 |
| If the above condition is '''false '''then it is skipped. | | If the above condition is '''false '''then it is skipped. | ||
|- | |- | ||
− | | 03 | + | | 03:45 |
| The control then jumps to the next statement. | | The control then jumps to the next statement. | ||
|- | |- | ||
− | | 03 | + | | 03:49 |
− | | Next comes the '''greater than or equal to '''operator. | + | | Next comes the '''greater than or equal to (>=) '''operator. |
|- | |- | ||
− | | 03 | + | | 03:52 |
− | | It compares '''a '''and '''b '''and | + | | It compares '''a '''and '''b '''and returns '''true''' if '''a''' is greater than or equal to '''b'''. |
|- | |- | ||
− | | 04 | + | | 04:00 |
| If the condition is true then this printf statement will be executed. | | If the condition is true then this printf statement will be executed. | ||
|- | |- | ||
− | | 04 | + | | 04:05 |
| Now let's execute the code till here. | | Now let's execute the code till here. | ||
|- | |- | ||
− | | 04 | + | | 04:07 |
| Click on '''Save'''. | | Click on '''Save'''. | ||
|- | |- | ||
− | | 04 | + | | 04:09 |
| Switch back to the terminal. | | Switch back to the terminal. | ||
|- | |- | ||
− | | 04 | + | | 04:12 |
| Compile and execute as before. | | Compile and execute as before. | ||
− | |||
|- | |- | ||
− | | 04 | + | | 04:17 |
| I enter '''a''' as 8 and '''b '''as 3. | | I enter '''a''' as 8 and '''b '''as 3. | ||
|- | |- | ||
− | | 04 | + | | 04:22 |
| The output is displayed: | | The output is displayed: | ||
|- | |- | ||
− | | 04 | + | | 04:25 |
− | | 8 is greater than or equal to 3 | + | | '''8 is greater than or equal to 3''' |
|- | |- | ||
− | | 04 | + | | 04:30 |
|Now Coming back to rest of the code. | |Now Coming back to rest of the code. | ||
|- | |- | ||
− | | 04 | + | | 04:33 |
− | | Delete the multiline comments from here | + | | Delete the multiline comments from here |
+ | |||
+ | |- | ||
+ | | 04:39 | ||
+ | | and here. | ||
|- | |- | ||
− | | 04 | + | | 04:43 |
− | | | + | |We now have the '''equal to '''operator. |
|- | |- | ||
− | | 04 | + | | 04:47 |
− | | It is denoted by | + | | It is denoted by '''double equal signs (==)'''. |
|- | |- | ||
− | | 04 | + | | 04:50 |
− | | This operator | + | | This operator returns '''true''' when both operands are equal to one another. |
|- | |- | ||
− | | 04 | + | | 04:57 |
|This '''printf''' statement executes when '''a''' is equal to '''b.''' | |This '''printf''' statement executes when '''a''' is equal to '''b.''' | ||
|- | |- | ||
− | | 05 | + | | 05:00 |
| If not, the control then jumps on to the next statement. | | If not, the control then jumps on to the next statement. | ||
|- | |- | ||
− | |05 | + | |05:06 |
|Similarly, we have the '''not equal to''' operator. | |Similarly, we have the '''not equal to''' operator. | ||
|- | |- | ||
− | | 05 | + | | 05:08 |
− | | This operator ''' | + | | This operator returns '''true''' when the operands are not equal to one another. |
|- | |- | ||
− | |05 | + | |05:15 |
− | | This '''printf''' | + | | This '''printf''' statement will execute when '''a''' is not equal to '''b'''. |
|- | |- | ||
− | | 05 | + | | 05:20 |
− | |Coming to the end of the program. | + | |Coming to the end of the program. '''return 0;''' |
− | + | ||
− | ''' | + | |
|- | |- | ||
− | | 05 | + | | 05:24 |
| Click on '''Save'''. | | Click on '''Save'''. | ||
|- | |- | ||
− | |05 | + | |05:26 |
| Switch back to the terminal. | | Switch back to the terminal. | ||
|- | |- | ||
− | | 05 | + | | 05:28 |
| Compile and execute as before. | | Compile and execute as before. | ||
− | |||
|- | |- | ||
− | | 05 | + | | 05:32 |
| Enter '''a''' as 8 and '''b '''as 3. | | Enter '''a''' as 8 and '''b '''as 3. | ||
|- | |- | ||
− | | 05 | + | | 05:38 |
| The output is displayed on the screen: | | The output is displayed on the screen: | ||
|- | |- | ||
− | | 05 | + | | 05:40 |
− | | 8 is not equal to 3 | + | | '''8 is not equal to 3''' |
|- | |- | ||
− | | 05 | + | | 05:44 |
− | | So, we see how the relational | + | | So, we see how the relational operators work. |
|- | |- | ||
− | | 05 | + | | 05:48 |
| Try executing this code with different set of inputs. | | Try executing this code with different set of inputs. | ||
|- | |- | ||
− | | 05 | + | | 05:51 |
− | | | + | | Now, writing a similar program in '''C++''' is quite easy. |
|- | |- | ||
− | | 05 | + | | 05:56 |
| There are a few differences in the syntax. | | There are a few differences in the syntax. | ||
|- | |- | ||
− | | | + | | 05:59 |
| I have already made the code in '''C++'''. | | I have already made the code in '''C++'''. | ||
|- | |- | ||
− | |06 | + | |06:04 |
− | | | + | | Here is the code for '''relational operators''' in '''C++'''. |
|- | |- | ||
− | |06 | + | |06:08 |
|Notice that the header is different. | |Notice that the header is different. | ||
|- | |- | ||
− | | 06 | + | | 06:12 |
| Also we have the '''using '''statement here. | | Also we have the '''using '''statement here. | ||
|- | |- | ||
− | | 06 | + | | 06:15 |
| The output statement in C++ is '''cout'''. | | The output statement in C++ is '''cout'''. | ||
|- | |- | ||
− | | 06 | + | | 06:19 |
| And the input statement in C++ is''' cin.''' | | And the input statement in C++ is''' cin.''' | ||
|- | |- | ||
− | | 06 | + | | 06:22 |
| So, apart from these differences, the two codes are very similar. | | So, apart from these differences, the two codes are very similar. | ||
|- | |- | ||
− | |06 | + | |06:26 |
− | | Click on | + | | Click on Save. |
|- | |- | ||
− | | 06 | + | | 06:28 |
− | | Please make sure the file is saved with the extension '''.cpp''' | + | | Please make sure the file is saved with the extension '''.cpp'''. |
|- | |- | ||
− | | 06 | + | | 06:32 |
− | | I have saved my file as '''relational.cpp''' | + | | I have saved my file as '''relational.cpp'''. |
|- | |- | ||
− | | 06 | + | | 06:37 |
| Let's compile the code. | | Let's compile the code. | ||
|- | |- | ||
− | | 06 | + | | 06:39 |
− | | Open the terminal and type '''g++ relational.cpp | + | | Open the terminal and type '''g++ relational.cpp space minus o space rel1''' |
|- | |- | ||
− | | 06 | + | | 06:50 |
− | | To execute | + | | To execute, type '''./rel1''' (dot slash rel1), press Enter. |
|- | |- | ||
− | | 06 | + | | 06:56 |
| I enter '''a''' as 8 and '''b '''as 3. | | I enter '''a''' as 8 and '''b '''as 3. | ||
|- | |- | ||
− | | 07 | + | | 07:00 |
| The output is displayed: | | The output is displayed: | ||
|- | |- | ||
− | | 07 | + | | 07:02 |
− | | We see that the output is same as the one in '''C''' | + | | We see that the output is same as the one in '''C''' program. |
|- | |- | ||
− | | 07 | + | | 07:07 |
| Now let us see an error which we can come across. | | Now let us see an error which we can come across. | ||
|- | |- | ||
− | | 07 | + | | 07:10 |
− | | Come back to the program | + | | Come back to the program. |
|- | |- | ||
− | | 07 | + | | 07:13 |
− | | Suppose here we replace the double equal to sign with the single equal to. | + | | Suppose here we replace the 'double equal to' sign with the 'single equal to'. |
|- | |- | ||
− | | 07 | + | | 07:19 |
| Click on '''Save.''' | | Click on '''Save.''' | ||
|- | |- | ||
− | | 07 | + | | 07:21 |
| Come back to the terminal. | | Come back to the terminal. | ||
|- | |- | ||
− | | 07 | + | | 07:23 |
| Compile and execute as before. | | Compile and execute as before. | ||
|- | |- | ||
− | | 07 | + | | 07:33 |
| Here we see it is showing 3 is equal to 3. | | Here we see it is showing 3 is equal to 3. | ||
|- | |- | ||
− | | 07 | + | | 07:37 |
− | | Come back to our program | + | | Come back to our program. |
|- | |- | ||
− | | 07 | + | | 07:40 |
| This is because here we have an assignment operator. | | This is because here we have an assignment operator. | ||
|- | |- | ||
− | | 07 | + | | 07:43 |
| So value of b is assigned to a. | | So value of b is assigned to a. | ||
|- | |- | ||
− | | 07 | + | | 07:46 |
− | |Now | + | |Now, let us fix this error. |
|- | |- | ||
− | | 07 | + | | 07:49 |
| Type an equal to sign. | | Type an equal to sign. | ||
|- | |- | ||
− | | 07 | + | | 07:51 |
− | | Click on '''Save''' | + | | Click on '''Save'''. |
|- | |- | ||
− | | 07 | + | | 07:54 |
− | | Switch back to the terminal | + | | Switch back to the terminal. |
|- | |- | ||
− | | 07 | + | | 07:56 |
− | | | + | | Compile and execute as before. |
|- | |- | ||
− | | 08 | + | | 08:04 |
| The output is now correct. | | The output is now correct. | ||
|- | |- | ||
− | |08 | + | |08:06 |
| Let's summarize the tutorial. | | Let's summarize the tutorial. | ||
|- | |- | ||
− | | 08 | + | | 08:08 |
| In this tutorial, we learnt | | In this tutorial, we learnt | ||
|- | |- | ||
− | | 08 | + | | 08:10 |
− | | | + | | relational operators like: |
|- | |- | ||
− | | 08 | + | | 08:12 |
− | | Less than: | + | | Less than: e.g. a < b |
|- | |- | ||
− | | 08 | + | | 08:14 |
− | | Greater than: | + | | Greater than: e.g. a>b |
|- | |- | ||
− | | 08 | + | | 08:17 |
− | | Less than or equal to: | + | | Less than or equal to: e.g. a<=b |
|- | |- | ||
− | | 08 | + | | 08:22 |
− | | Greater than or equal to: | + | | Greater than or equal to: e.g. a>=b |
|- | |- | ||
− | | 08 | + | | 08:27 |
− | | Equal to: | + | | Equal to: e.g. a==b |
|- | |- | ||
− | | 08 | + | | 08:29 |
− | | Not equal to: | + | | Not equal to: e.g. a!=b |
|- | |- | ||
− | | 08 | + | | 08:34 |
− | | As an assignment | + | | As an assignment: |
|- | |- | ||
− | | 08 | + | | 08:35 |
| Write a program that takes the marks of three students as input. | | Write a program that takes the marks of three students as input. | ||
|- | |- | ||
− | | 08 | + | | 08:39 |
| Compare the marks to see which student has scored the highest. | | Compare the marks to see which student has scored the highest. | ||
|- | |- | ||
− | | 08 | + | | 08:43 |
| Check also if two or more students have scored equal marks. | | Check also if two or more students have scored equal marks. | ||
|- | |- | ||
− | | 08 | + | | 08:48 |
− | | Watch the video available at the following link | + | | Watch the video available at the following link. |
+ | |||
|- | |- | ||
− | | 08 | + | | 08:51 |
− | | It summarizes the Spoken Tutorial project | + | | It summarizes the Spoken Tutorial project. |
+ | |||
|- | |- | ||
− | | 08 | + | | 08:54 |
− | | 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. |
|- | |- | ||
− | | 08 | + | | 08:58 |
− | | The Spoken Tutorial Project Team | + | | The Spoken Tutorial Project Team: |
|- | |- | ||
− | | 09 | + | | 09:00 |
− | | Conducts workshops using spoken tutorials | + | | Conducts workshops using spoken tutorials. |
|- | |- | ||
− | | 09 | + | | 09:03 |
− | | Gives certificates for those who pass an online test | + | | Gives certificates for those who pass an online test. |
|- | |- | ||
− | | 09 | + | | 09:06 |
− | | 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. |
− | + | ||
− | + | ||
|- | |- | ||
− | | 09 | + | | 09:14 |
− | | 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. |
|- | |- | ||
− | | 09 | + | | 09:18 |
− | | 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. |
|- | |- | ||
− | | 09 | + | | 09:24 |
| More information on this Mission is available at | | More information on this Mission is available at | ||
|- | |- | ||
− | | 09 | + | | 09:27 |
− | | spoken hyphen tutorial dot org slash NMEICT hyphen Intro | + | | spoken hyphen tutorial dot org slash NMEICT hyphen Intro. |
|- | |- | ||
− | | 09 | + | | 09:34 |
− | | This is Ritwik Joshi from IIT Bombay. | + | | This is Ritwik Joshi from IIT Bombay.Thank you for joining. |
− | + | ||
− | Thank you for joining. | + | |
|} | |} |
Latest revision as of 14:20, 24 March 2017
Time | Narration |
00:01 | Welcome to the spoken tutorial on Relational Operators in C and C++. |
00:06 | In this tutorial, we will learn about: |
00:09 | Relational operators like, |
00:11 | Less than: e.g. a < b |
00:14 | Greater than: e.g. a > b |
00:17 | Less than or equal to: e.g. a <= b |
00:22 | Greater than or equal to: e.g. a >= b |
00:27 | Equal to: e.g. a == b |
00:30 | Not equal to: e.g. a != b |
00:37 | To record this tutorial, I am using: Ubuntu 11.10 as the operating system, |
00:42 | gcc and g++ Compiler version 4.6.1 in Ubuntu. |
00:50 | Let us begin with an introduction. |
00:53 | Relational operators are used to compare integer and floating point numbers. |
00:57 | Expressions using relational operators return 0 for false and 1 for true. |
01:04 | Now I will demonstrate the relational operators with the help of a C program. |
01:09 | I have already made the program. |
01:11 | So, I'll open the editor and explain the code. |
01:15 | First, we declare two variables a and b. |
01:20 | This printf statement prompts the user to enter the values of a and b. |
01:26 | This scanf statement takes input for the variables a and b. |
01:32 | Now we have the greater than (>) operator. |
01:35 | This operator compares the two operands on either side of the operator. |
01:38 | It returns True if a is greater than b. |
01:43 | This printf statement is executed if the above condition is true. |
01:47 | If the above condition is false then it is skipped. |
01:50 | The control then jumps to the next statement. |
01:53 | We now have the less than (<) operator. |
01:56 | This too compares the operands. |
01:57 | It returns true when a is less than b. |
02:02 | This printf statement is executed if the above condition is true. |
02:06 | It is skipped otherwise. |
02:09 | Let's execute the code till here. |
02:13 | First comment out the following. |
02:16 | Type /* (slash asterisk) |
02:21 | */ (asterisk slash). |
02:24 | Click on Save. |
02:26 | I have saved my file as relational.c. |
02:29 | Open the terminal window by pressing Ctrl, Alt and T keys simultaneously. |
02:35 | To compile, type the following on the terminal gcc space relational dot c space -o space rel. |
02:49 | Press Enter. |
02:51 | To execute, type ./rel (dot slash rel). Press Enter. |
02:56 | I enter a as 8 and b as 3. |
03:01 | The output is displayed: |
03:03 | 8 is greater than 3. |
03:07 | You can try executing this code with different values of a and b. |
03:11 | Coming back to the code. |
03:14 | Delete the comment from here |
03:18 | and put it here. |
03:24 | Now we have the less than or equal to (<=) operator. |
03:28 | This operator compares the two operands on either side of the operator. |
03:33 | It returns true if a is less than or equal to b. |
03:38 | This printf statement is executed if the above condition is true. |
03:42 | If the above condition is false then it is skipped. |
03:45 | The control then jumps to the next statement. |
03:49 | Next comes the greater than or equal to (>=) operator. |
03:52 | It compares a and b and returns true if a is greater than or equal to b. |
04:00 | If the condition is true then this printf statement will be executed. |
04:05 | Now let's execute the code till here. |
04:07 | Click on Save. |
04:09 | Switch back to the terminal. |
04:12 | Compile and execute as before. |
04:17 | I enter a as 8 and b as 3. |
04:22 | The output is displayed: |
04:25 | 8 is greater than or equal to 3 |
04:30 | Now Coming back to rest of the code. |
04:33 | Delete the multiline comments from here |
04:39 | and here. |
04:43 | We now have the equal to operator. |
04:47 | It is denoted by double equal signs (==). |
04:50 | This operator returns true when both operands are equal to one another. |
04:57 | This printf statement executes when a is equal to b. |
05:00 | If not, the control then jumps on to the next statement. |
05:06 | Similarly, we have the not equal to operator. |
05:08 | This operator returns true when the operands are not equal to one another. |
05:15 | This printf statement will execute when a is not equal to b. |
05:20 | Coming to the end of the program. return 0; |
05:24 | Click on Save. |
05:26 | Switch back to the terminal. |
05:28 | Compile and execute as before. |
05:32 | Enter a as 8 and b as 3. |
05:38 | The output is displayed on the screen: |
05:40 | 8 is not equal to 3 |
05:44 | So, we see how the relational operators work. |
05:48 | Try executing this code with different set of inputs. |
05:51 | Now, writing a similar program in C++ is quite easy. |
05:56 | There are a few differences in the syntax. |
05:59 | I have already made the code in C++. |
06:04 | Here is the code for relational operators in C++. |
06:08 | Notice that the header is different. |
06:12 | Also we have the using statement here. |
06:15 | The output statement in C++ is cout. |
06:19 | And the input statement in C++ is cin. |
06:22 | So, apart from these differences, the two codes are very similar. |
06:26 | Click on Save. |
06:28 | Please make sure the file is saved with the extension .cpp. |
06:32 | I have saved my file as relational.cpp. |
06:37 | Let's compile the code. |
06:39 | Open the terminal and type g++ relational.cpp space minus o space rel1 |
06:50 | To execute, type ./rel1 (dot slash rel1), press Enter. |
06:56 | I enter a as 8 and b as 3. |
07:00 | The output is displayed: |
07:02 | We see that the output is same as the one in C program. |
07:07 | Now let us see an error which we can come across. |
07:10 | Come back to the program. |
07:13 | Suppose here we replace the 'double equal to' sign with the 'single equal to'. |
07:19 | Click on Save. |
07:21 | Come back to the terminal. |
07:23 | Compile and execute as before. |
07:33 | Here we see it is showing 3 is equal to 3. |
07:37 | Come back to our program. |
07:40 | This is because here we have an assignment operator. |
07:43 | So value of b is assigned to a. |
07:46 | Now, let us fix this error. |
07:49 | Type an equal to sign. |
07:51 | Click on Save. |
07:54 | Switch back to the terminal. |
07:56 | Compile and execute as before. |
08:04 | The output is now correct. |
08:06 | Let's summarize the tutorial. |
08:08 | In this tutorial, we learnt |
08:10 | relational operators like: |
08:12 | Less than: e.g. a < b |
08:14 | Greater than: e.g. a>b |
08:17 | Less than or equal to: e.g. a<=b |
08:22 | Greater than or equal to: e.g. a>=b |
08:27 | Equal to: e.g. a==b |
08:29 | Not equal to: e.g. a!=b |
08:34 | As an assignment: |
08:35 | Write a program that takes the marks of three students as input. |
08:39 | Compare the marks to see which student has scored the highest. |
08:43 | Check also if two or more students have scored equal marks. |
08:48 | Watch the video available at the following link. |
08:51 | It summarizes the Spoken Tutorial project. |
08:54 | If you do not have good bandwidth, you can download and watch it. |
08:58 | The Spoken Tutorial Project Team: |
09:00 | Conducts workshops using spoken tutorials. |
09:03 | Gives certificates for those who pass an online test. |
09:06 | For more details, please write to contact at spoken hyphen tutorial dot org. |
09:14 | Spoken Tutorial Project is a part of the Talk to a Teacher project. |
09:18 | It is supported by the National Mission on Education through ICT, MHRD, Government of India. |
09:24 | More information on this Mission is available at |
09:27 | spoken hyphen tutorial dot org slash NMEICT hyphen Intro. |
09:34 | This is Ritwik Joshi from IIT Bombay.Thank you for joining. |
Contributors and Content Editors
Ashwini, PoojaMoolya, Pratik kamble, Priyacst, Sakinashaikh, Sandhya.np14