C-and-C++/C3/Arrays/English-timed
From Script | Spoken-Tutorial
Time | Narration |
00:01 | Welcome to the spoken-tutorial on Arrays in C and C++. |
00:07 | In this tutorial we will learn: |
00:09 | What is an array |
00:11 | Declaration of an array |
00:13 | Initialization of an array |
00:16 | Few Examples on array. |
00:18 | We will also see some common errors and their solutions. |
00:22 | To record this tutorial, I am using |
00:25 | Ubuntu Operating System version 11.04, |
00:30 | gcc and g++ Compiler version 4.6.1 . |
00:36 | Let us start with the introduction to Array. |
00:39 | Array is the collection of data or elements of same data-type. |
00:44 | Array index starts from 0. |
00:48 | The first element is stored at index 0. |
00:52 | There are three types of arrays: |
00:55 | Single dimensional array |
00:57 | Two dimensional array and |
00:59 | Multi-dimensional array. |
01:01 | We will be discussing single dimensional array in this tutorial. |
01:06 | Let us see how to declare single dimensional array. |
01:09 | The Syntax for this is: |
01:11 | data-type name of the array and size |
01:16 | example, here we have declared an integer array 'star' which contains 5 elements. |
01:24 | The array index will start from star 0 to star 4. |
01:29 | We saw the declaration of an array. |
01:32 | Now, we will see the initialization of an array. |
01:35 | The Syntax for this is: |
01:38 | data-type,( name of the array ), size is equal to elements |
01:44 | example: here we have declared an 'integer array star' with size 3. The elements of the array are 1,2 and 3. |
01:54 | Here the index will start from star 0 to star 2. |
01:59 | Now, lets us move to the examples. |
02:01 | I have already typed the program on the editor. |
02:04 | So, let me open it. |
02:06 | Please note that our file name is array.c |
02:10 | In this program, we will calculate the sum of the elements stored in an array. |
02:16 | Let me explain the code now. |
02:18 | This is our header file. |
02:20 | This is our main() function. |
02:22 | Here, we have declared and initialized an array star with size 3. |
02:28 | The elements of the array are 4, 5 and 6. |
02:33 | Then we have declared an 'integer variable' sum. |
02:36 | Here we add the elements of the array and store the result in sum. |
02:41 | Note that 4 will be stored at index 0, 5 will be stored at index 1 and 6 will be stored at index 2. |
02:50 | Then we print the sum. |
02:52 | This is our return statement. |
02:54 | Now, click on Save. |
02:57 | Let us execute the program. |
02:59 | Please open the terminal window by pressing Ctrl, Alt and T keys simultaneously on your keyboard. |
03:09 | To compile, type gcc space array dot c space hypen o array and press Enter. |
03:19 | To execute, type dot slash array (./array). Press Enter. |
03:24 | Here the output is displayed as, |
03:26 | The sum is 15. |
03:28 | Now let us see some common errors which we can come across. |
03:32 | Come back to our program. |
03:34 | Suppose, here at line number 4, we miss the curly brackets. |
03:39 | Click on Save. Let us see what happens. |
03:42 | Come back to the terminal. |
03:44 | Let us compile as before. |
03:47 | We see an error: |
03:49 | Invalid initializer and Expected identifier or bracket before numeric constant. |
03:56 | This is because arrays must be initialized within curly brackets. |
04:01 | Come back to our program. Let us fix the error. |
04:04 | Type the curly brackets here at line number 4. |
04:09 | Now, click on Save. |
04:12 | Lets us execute. Come back to the terminal. |
04:15 | Let us compile as before. Let us execute as before. |
04:19 | Yes, it is working. |
04:21 | Now we will execute the same program in C++. |
04:25 | Come back to our program. |
04:28 | I will change a few things here. |
04:30 | First, press Shift , Ctrl and S keys simultaneously on your keyboard. |
04:38 | Now save the file with the extension dot cpp (.cpp) and click on Save. |
04:44 | Let us change the header file as iostream. |
04:49 | Now include the using statement. |
04:55 | The declaration and initialization of an array is same in C++. |
05:01 | Hence no need to change anything here. |
05:04 | Now replace the printf statement with the cout statement. |
05:09 | Delete the format specifier and backslash n (\n), now delete the comma and type two opening angle brackets. |
05:17 | Delete the bracket here. Again type two opening angle brackets and within the double quotes type backslash n (\n). |
05:26 | Now, click on Save. |
05:29 | Let us execute. Come back to a terminal. |
05:32 | To compile, type g++ space array dot cpp space hyphen o space array1 |
05:42 | Here we have array1 because we don't want to overwrite the output parameter array for the file array dot c. |
05:51 | Now press Enter. |
05:54 | To execute type, dot slash array1(./array1) . Press Enter. |
05:59 | The output is displayed as: The sum is 15 |
06:02 | We can see that it is similar to our C code. |
06:07 | Now, we will see another common error. |
06:10 | Come back to our program. |
06:12 | Suppose here, at line number 7, |
06:14 | I will type star[1], star[2] and star[3]; |
06:23 | click on Save.Let us execute. Come back to our terminal. |
06:28 | Let me clear the prompt. |
06:30 | Let us compile as before. |
06:33 | Let us execute as before. |
06:36 | We get an unexpected output. |
06:39 | This is because array index starts from 0. |
06:43 | Come back to our program. We can see here the array index starts from one. |
06:49 | Hence it is giving an error. Let us fix the error. |
06:54 | Type 0 here 1 and 2. Click on Save. |
07:02 | Let us execute. Come back to our terminal. |
07:05 | Let us compile as before. Execute as before. |
07:09 | Yes, it is working. |
07:12 | Now, we will go back to our slides. |
07:14 | Le us summarize. |
07:16 | In this tutorial we learned: |
07:19 | Arrays , To declare Single Dimensional Arrays |
07:23 | To initialize Single Dimensional Arrays |
07:26 | example int star[3]={4, 5, 6} |
07:31 | To add the elements of the array, example sum is equal to star 0 plus star 1 plus star 2. |
07:40 | As an assignment, write a program to calculate the difference of the elements stored in an array. |
07:47 | Watch the video available at the link shown below. |
07:50 | It summarizes the Spoken Tutorial project. |
07:53 | If you do not have good bandwidth, you can download and watch it. |
07:57 | The Spoken Tutorial Project Team: |
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08:06 | For more details, please write to, contact@spoken-tutorial.org. |
08:13 | Spoken Tutorial Project is a part of Talk to a Teacher project. |
08:17 | It is supported by the National Mission on Education through ICT, MHRD, Government of India. |
08:25 | More information on this mission is available at the link shown below. |
08:30 | This is Ashwini Patil from IIT Bombay, signing off. |
08:33 | Thank You for watching. |