Java/C2/For-Loop/English

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Title of script: for loop in Java

Author: TalentSprint

Keywords: conditions, loops, for loop, video tutorial


Visual Cue Description
Slide 1

Welcome

Welcome to the spoken tutorial on for loop.
Slide 2

Learning Outcomes

In this tutorial, you will learn how to use the for loop in Java.
Slide 3

Tools Used

For this tutorial we are using
  • Ubuntu 11.10,
  • JDK 1.6 and
  • Eclipse 3.7.0


Slide 4

Prerequisites

For this tutorial, you should have knowledge on relational operators and if statement in Java.


If not, please go through the tutorials on these topics available at our website http://spoken-tutorial.org.

Slide 5

Syntax

Here is the syntax of the for loop.


Now, let us try out an example in Eclipse.

Minimize Slides and open Eclipse

Eclipse should contain the following code

public class ForLoopDemo{

public static void main(String[] args){

}

}

We have the skeleton required.


We have a class named ForLoopDemo.


Let us add the for loop inside the main method.

Inside the main function, type

int i;

for (i = 0; i < 10; i = i + 1)


Highlight when you explain.

Inside the main function, type int i semicolon.


Then type for within brackets i equal to 0 semicolon i less than 10 semicolon i equal to i plus 1.


This statement decides how the loop is going to progress.

Highlight i = 0 This is the starting condition for the loop.


This condition allows the variable to be initialized.

Highlight i < 10 This is the loop running condition.


If the condition is true then the for block will be executed.


Else it will be ignored.


That means when i becomes more than or equal to 10, the block is not executed.

Highlight i = i + 1 This states how the loop variable is going to change.


Here, the value of i starts with 0.


It keeps increasing by 1 for every iteration of the loop until it becomes 10.


Now let us do something with i.

Change for (i = 0; i < 10; i = i + 1) to for (i = 0; i < 10; i = i + 1) {

System.out.println( i * i );

}


Highlight the println statement and explain.

Now, open and close curly brackets.


Next line type System dot out dot println within brackets i into i.


This will print the square of each number from 0 to 9.


Let us see the output.


So save and run the file.

Save and run. Point to output As we can see, the loop ran over numbers from 0 to 9.


The square of the number has been printed in each iteration.


Now let us print all the 2 digit numbers that are multiples of 3 or 5.

Change i = 0 to i = 10 So, i should have values from 10 to 99.


So change i equal to 0 to i equal to 10.

Change i < 10 to i < 100 Change i less than 10 to i less than 100.
Change System.out.println( i * i ) to

if ((i % 3 == 0) || (i % 5 == 0)){

System.out.println(i);

}

Delete System dot out dot println within brackets i into i.


We print the number only if it is a multiple of 3 or 5.


So type,

if within brackets i mod 3 double equal to 0 or i mod 5 double equal to 0.


This statement checks whether i is divisible by 3 or by 5.


Then, next line type System dot out dot println within brackets i.


Now, let us see the output.



Save and run. Highlight the output We can see that the numbers are either multiples of 3 or of 5.
Minimize the Eclipse window and switch to slides.


Slide 6

Summary

We have come to the end of this tutorial.

In this tutorial we have learnt how to use for loop in java.

Slide 7Assignment A three digit number is called Armstrong Number if it is equal to the sum of cubes of its digits.


For example, 153 is equal to 1 cube plus 5 cube plus 3 cube.


Find all such 3 digit numbers.

Slide 8About the Spoken Tutorial Project
  • It summarises the Spoken Tutorial project
  • If you do not have good bandwidth, you can download and watch it


To know more about the Spoken Tutorial project, watch the video available at the following link, that summarises the project.Alternatively, you can download and watch it.
Slide 9Spoken Tutorial WorkshopsThe Spoken Tutorial Project Team
  • Conducts workshops using spoken tutorials
  • Gives certificates for those who pass an online test


The Spoken Tutorial Project Team. Conducts workshops using spoken tutorials and gives certificates for those who pass an online test. For more details, please write to contact AT spoken HYPHEN tutorial DOT org.
Slide 10Acknowledgement
  • Spoken Tutorial Project is a part of the Talk to a Teacher project
  • It is supported by the National Mission on Education through ICT, MHRD, Government of India
  • More information on this Mission is available at


Spoken Tutorial Project is a part of the Talk to a Teacher project and is supported by the National Mission on Education through ICT, MHRD, Government of India. More information on this Mission is available at spoken HYPHEN tutorial DOT org SLASH NMEICT HYPHEN Intro
Slide 11About the contributor
  • This script has been contributed by TalentSprint
  • www.talentsprint.com
  • Thanks for joining


This script has been contributed by TalentSprint.

This is Prathamesh Salunke signing off.

Thanks for joining.



Contributors and Content Editors

Arya Ratish, Pratham920, Sneha