C-and-C++/C3/Arrays/English-timed

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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 initialize 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 accross.
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 back slash 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 hypen 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 . 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.
06:24 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
07:20 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 element of the array, example sum is equal to star 0 plus star 1 plus star 2.
07:40 As an assignment,
07:41 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:
08:00 Conducts workshops using spoken tutorials.
08:03 Gives certificates to those who pass an online test.
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.

Contributors and Content Editors

Kavita salve, PoojaMoolya, Pratik kamble, Sandhya.np14