Category: Uncategorized

Design and Analysis of Algorithms
Design and Analysis of Algorithms

Analysis of Algorithms is a fundamental aspect of computer science that involves evaluating performance of algorithms and programs. Efficiency is measured in terms of time and space.

Design and Analysis of Algorithms Tutorial

An Algorithm is a sequence of steps to solve a problem. It acts like a set of instructions on how a program should be executed. Thus, there is no fixed structure of an algorithm. Design and Analysis of Algorithms covers the concepts of designing an algorithm as to solve various problems in computer science and information technology, and also analyze the complexity of these algorithms designed.

The main aim of designing an algorithm is to provide a optimal solution for a problem. Not all problems must have similar type of solutions; an optimal solution for one problem may not be optimal for another. Therefore, we must adopt various strategies to provide feasible solutions for all types of problems.

This tutorial introduces the fundamental concepts of Designing Strategies, Complexity analysis of Algorithms, followed by problems on Graph Theory and Sorting methods. This tutorial also includes the basic concepts on Complexity theory.

Why Design and Analysis of Algorithms?

One computer problem might have several versions of a solution. In this case, every approach taken to solve the computer problem is correct. However, choosing the best-suited solution will improve the efficiency of the program.

There might be a misconception that smaller algorithms are best-suited solutions in most cases. But, a feasible solution is not based on the length of algorithm, but the one with efficient complexity (time and space complexity).

We study Design and Analysis of Algorithms to analyse the complexity of all the versions of a solution to a computer problem.

Design Strategies

There are various types of strategies in order to design algorithms for various problems. Some of them are listed as follows −
- Greedy Approach
- Divide & Conquer Approach
- Dynamic Programming Approach
- Randomization Approach
- Approximation Approach
- Recursive Approach
- Branch and Bound Approach
Analysis of Algorithms

To analyze the feasibility of an algorithm designed, we calculate the complexity of it. This is represented in three notations, called asymptotic notations. Asymptotic notations are as follows −
- Worst-Case Scenario − Big Oh and Little Oh Notations
- Best-Case Scenario − Big Omega and Little Omega Notations
- Average-Case Scenario − Theta Notation
Each solution is analyzed in all scenarios of the problem, and the solution having the best worst-case is said to be optimal. Thus, providing an efficient algorithm.

Applications of DAA

There are applications of Design and Analysis of Algorithms (DAA) in a wide range of fields. Here are some of the common fields where it is used:
- Computer programming: Used in computer programming to solve problems efficiently. This includes developing algorithms for sorting, searching, and manipulating data structures.
- Big data processing: Also used to develop and analyse algorithms for operations such as data mining, machine learning, and natural language processing, in order to handle large sets of data.
- Networking: Network protocols and algorithms are developed for routing, flow control, congestion control, and network security. DAA is used to design and analyse these algorithms.
- Artificial intelligence: Used to design and analyse algorithms for tasks in Artificial Intelligence such as computer vision, speech recognition, and natural language understanding.
- Scientific computing: DAA in scientific computing is used to develop algorithms for operations like numerical integration, optimization, and simulation.
- Game development: In game development, we use design and analysis of algorithms for pathfinding, collision detection, and physics simulation.
- Cryptography: DAA is also used in the design and analysis of cryptographic algorithms, such as RSA and AES, which are used to secure data transmission and storage.
Who Should Learn DAA

This tutorial has been designed for students pursuing a degree in any computer science, engineering, and/or information technology related fields. It attempts to help students to grasp the essential concepts involved in algorithm design.

Prerequisites to Learn DAA

The readers should have basic knowledge of programming and mathematics. The readers should know data structure very well. Moreover, it is preferred if the readers have basic understanding of Formal Language and Automata Theory.

DAA Jobs and Opportunities

Many top companies are actively recruiting experts in Design and Analysis of Algorithms, and they offer roles such as Software Engineer, Data Scientist, Machine Learning Engineer, and more. These companies need individuals who can solve complex problems, analyse data, and design algorithms to drive their business forward. Here is the list of few such companies −
- Google
- Amazon
- Microsoft
- Apple
- Adobe
- JPMorgan Chase
- Goldman Sachs
- Walmart
- Johnson & Johnson
- Airbnb
- Tesla
The demand for DAA professionals is continually growing across various sectors. By developing expertise in these areas, you can open up a wide range of career opportunities in some of the world’s leading companies.

To get started, there are user-friendly tutorials and resources available to help you master DAA. These materials are designed to prepare you for technical interviews and certification exams, and you can learn at your own pace, anytime and anywhere.
04.05.2025

Default Keyboard Shortcuts

Alice Koreman edited this page on May 15, 2023 · 21 revisions

Line Operations

Windows/Linux	Mac	Action
Ctrl-D	Command-D	Remove line
Alt-Shift-Down	Command-Option-Down	Copy lines down
Alt-Shift-Up	Command-Option-Up	Copy lines up
Alt-Down	Option-Down	Move lines down
Alt-Up	Option-Up	Move lines up
Alt-Delete	Ctrl-K	Remove to line end
Alt-Backspace	Command-Backspace	Remove to linestart
Ctrl-Backspace	Option-Backspace, Ctrl-Option-Backspace	Remove word left
Ctrl-Delete	Option-Delete	Remove word right
—	Ctrl-O	Split line

Selection

Windows/Linux	Mac	Action
Ctrl-A	Command-A	Select all
Shift-Left	Shift-Left	Select left
Shift-Right	Shift-Right	Select right
Ctrl-Shift-Left	Option-Shift-Left	Select word left
Ctrl-Shift-Right	Option-Shift-Right	Select word right
Shift-Home	Shift-Home	Select line start
Shift-End	Shift-End	Select line end
Alt-Shift-Right	Command-Shift-Right	Select to line end
Alt-Shift-Left	Command-Shift-Left	Select to line start
Shift-Up	Shift-Up	Select up
Shift-Down	Shift-Down	Select down
Shift-PageUp	Shift-PageUp	Select page up
Shift-PageDown	Shift-PageDown	Select page down
Ctrl-Shift-Home	Command-Shift-Up	Select to start
Ctrl-Shift-End	Command-Shift-Down	Select to end
Ctrl-Shift-D	Command-Shift-D	Duplicate selection
Ctrl-Shift-P	—	Select to matching bracket
Ctrl-Shift-M	Ctrl-Shift-M	Expand to matching
Ctrl-, Ctrl-P	Command-\	Jump to matching
Ctrl-Shift-, Ctrl-Shift-P	Command-Shift-\	Select to matching
Ctrl-Shift-L	Command-Shift-L	Expand to line

Multicursor

Windows/Linux	Mac	Action
Ctrl-Alt-Up	Ctrl-Option-Up	Add cursor above
Ctrl-Alt-Down	Ctrl-Option-Down	Add cursor below
Ctrl-Alt-Right	Ctrl-Option-Right	Add next occurrence to multi-selection
Ctrl-Alt-Left	Ctrl-Option-Left	Add previous occurrence to multi-selection
Ctrl-Alt-Shift-Up	Ctrl-Option-Shift-Up	Move multicursor from current line to the line above
Ctrl-Alt-Shift-Down	Ctrl-Option-Shift-Down	Move multicursor from current line to the line below
Ctrl-Alt-Shift-Right	Ctrl-Option-Shift-Right	Remove current occurrence from multi-selection and move to next
Ctrl-Alt-Shift-Left	Ctrl-Option-Shift-Left	Remove current occurrence from multi-selection and move to previous
Ctrl-Shift-L	Ctrl-Shift-L	Select all from multi-selection
Ctrl-Alt-A	Ctrl-Alt-A	Align cursors

Go to

Windows/Linux	Mac	Action
Left	Left, Ctrl-B	Go to left
Right	Right, Ctrl-F	Go to right
Ctrl-Left	Option-Left	Go to word left
Ctrl-Right	Option-Right	Go to word right
Up	Up, Ctrl-P	Go line up
Down	Down, Ctrl-N	Go line down
Alt-Left, Home	Command-Left, Home, Ctrl-A	Go to line start
Alt-Right, End	Command-Right, End, Ctrl-E	Go to line end
PageUp	Option-PageUp	Go to page up
PageDown	Option-PageDown, Ctrl-V	Go to page down
Ctrl-Home	Command-Home, Command-Up	Go to start
Ctrl-End	Command-End, Command-Down	Go to end
Ctrl-L	Command-L	Go to line…
Ctrl-Down	Command-Down	Scroll line down
Ctrl-Up	—	Scroll line up
Ctrl-P	—	Go to matching bracket
—	Option-PageDown	Scroll page down
—	Option-PageUp	Scroll page up
Alt-E	F4	Go to next error
Alt-Shift-E	Shift-F4	Go to previous error

Find/Replace

Windows/Linux	Mac	Action
Ctrl-F	Command-F	Find
Ctrl-H	Command-Option-F	Replace
Ctrl-K	Command-G	Find next
Ctrl-Shift-K	Command-Shift-G	Find previous
Ctrl-Alt-K	Ctrl-Alt-G	Find all
Alt-K	Ctrl-G	Select or find next
Alt-Shift-K	Ctrl-Shift-G	Select or find previous

Folding

Windows/Linux	Mac	Action
F2	F2	Toggle fold widget
Alt-F2	Alt-F2	Toggle parent fold widget
Alt-L, Ctrl-F1	Command-Option-L, Command-F1	Fold selection
Alt-Shift-L, Ctrl-Shift-F1	Command-Option-Shift-L, Command-Shift-F1	Unfold
Alt-0	Command-Option-0	Fold all
Alt-Shift-0	Command-Option-Shift-0	Unfold all
—	Ctrl-Command-Option-0	Fold all comments

Other

Windows/Linux	Mac	Action
F1	F1	Open command palette
Tab	Tab	Indent
Ctrl-]	Ctrl-]	Block indent
Shift-Tab	Shift-Tab	Outdent
Ctrl-[	Ctrl-[	Block outdent
Ctrl-Z	Command-Z	Undo
Ctrl-Shift-Z, Ctrl-Y	Command-Shift-Z, Command-Y	Redo
Ctrl-,	Command-,	Show the settings menu
Ctrl-/	Command-/	Toggle comment
Ctrl-Shift-/	Command-Shift-/	Toggle block comment
Ctrl-T	Ctrl-T	Transpose letters
Ctrl-Enter	Command-Enter	Enter full screen
Ctrl-Shift-U	Ctrl-Shift-U	Change to lower case
Ctrl-U	Ctrl-U	Change to upper case
Insert	Insert	Overwrite
Ctrl-Shift-E	Command-Shift-E	Macros replay
Ctrl-Alt-E	—	Macros recording
Delete	—	Delete
—	Ctrl-L	Center selection
Ctrl-U	Ctrl-U	To uppercase
Ctrl-Shift-U	Ctrl-Shift-U	To lowercase
Ctrl-Alt-S	Command-Alt-S	Sort lines
Ctrl-Shift-Up	Alt-Shift-Up	Modify number up
Ctrl-Shift-Down	Alt-Shift-Down	Modify number down
Ctrl-Shift-B	Ctrl-Shift-B	Format selection (Beautify)

04.05.2025

Software Requirement Elicitation Technique Basic Concept
Requirements Elicitation Technique

Techniques for gathering requirements:
```
01. Stakeholder Analysis
02. Brainstorming
03. One On One Interview
04. Group Interview
05. Document Analysis
06. Focus Group
07. Interface Analysis
08. Observation Social Analysis
09. Prototyping
10. Facilitated sessions
11. Joint Application Development (IAD)
12. Questionnaire
13. Survey
14. Use cases and scenarios (UCD)
15. Reused Requirements
16. Request for proposals ( RFPs)
17. Reverse Engineering
```
01. Stakeholder analysis identifies Benefits

Stakeholder analysis identifies all the users and stakeholders who may influence or be impacted by the system.
This helps ensure that the needs of all those involved are taken into stakeholders are taken into account.
Benefit:
Ensures that all relevant stakeholders are considered.
All important stakeholders are captured, and yet that irrelevant actor are not included.
Drawbacks:
There is a danger that too much time is spent on identifying roles and relationships, and the team is swamped with data.

02. Brainstorming

It is utilized in requirements elicitation to gather good number of ideas from a group of people.
Usually brainstorming is used in identifying all possible solutions to problems and simplifies the the brainstorming detail of opportunities. It casts a broad session net determining various discreet possibilities.
Basic Rules:
1. Start out
2. Generate as may
3. Let your imagination soar.
4. Do not allow criticism or debate while you are gathering information.
5. Once information is gathered, reshape and combine ideas.
Benefits
Generate a variety of ideas in a short time.
Produce new and creative ideas
Risk
1. The risk of having a bad session.
2. Making stuff scared to voice their ideas because they were criticized in the session.
3. Problems normally occur if you only use traditional brainstorming technique.

03. One On One Interview

The most common tec nique for gathering requirements is to sit down with the clients and ask them what they need. The • Privacy of everyone discussion should be planned • in-depth a stakeholder’s out ahead of time based on the type of requirements you’re thoughts and get his or king for her perspective
Risks & Drawbacks
• Time Consuming
• Misunderstandings

04. Group Interview

If there are more then one person during interview usually 2 or 4 these people must be on • we can get hidden requirements
some level must be on some level • uncover a richer set of less time required requirements in a shorter period of time
• Uncover ambiguities
• Not relaxed environment
• Conflicts
• The allotted time have been exhausted

05. Document Analysis

Do you Analysis is an important gathering technique.
Evaluating the documentation of a
• validating the requirement present system can assist when completeness. making AS-1S process documents ▪ Chunks of information are mostly and also when driving the gap buried in present documents analysis for scoping of the • A beginning point for documenting all current requirements. migration projects.
▪ Time Consuming
▪ Conflicts
▪ Exhausted
• Not Found Real Figures

06. focus group

A focus group is actually gathering of • Managed process with particular people who are customers or users participants
• refine and validate the already representatives for a product to gain its elicited requirements

feedback. The feedback can be collected • Allows analyst to rapidly obtain a about opportunities, needs, and wide variety of user views and possibly a consensus.
problems to determine requirements or it can be collected to refine and validate

the already elicited requirements. • following the crowd and some
people think that focus groups are at best unproductive

• end up with is with least common denominator features.

• Recruitment effort to

• Assemble groups. Dominant participants may influence group disproportionately

07. Interface Analysis

Interface for any software product will either be human or machine.
Integration with external devices and systems is another interface. The
user centric design approaches are quite effective to ensure that you make usable software. Interface analysis- analyzing the touch points with another external system- is vital to ensure that you do not overlook requirements that are not instantly visible to the users. requirements that are not instantly visible to the users.

08. Observation or Social Analysis

Social analysis is also know s

Observation. Observation is the method
of collecting requirements by observing • The ability to record and
report all findings that are
the people doing their normal work. true
This method is generally used to find the • it is more practical
additional requirements needed by the • no long calculation has to be
user, when the user is unable to explain done

their expected requirements From the
new product and problems with the Risks & Drawbacks

existing product • The viewer’s or researcher’s
own perception
▪ few trials/studiesJor objects
observed to make an end
conclusion
• results may contain human
error

09. Prototyping

Prototyping is a relatively modern technique
for gathering requirements. In this approach, • prototypes can be ideal
you gather preliminary requirements that you reduce design risk
use to build an initial version of the solution ▪ it is more practical
a prototype. You show this to the client, • Screen mock-ups
who then gives you additional requirements. • Using animation tools
You change the application and cycle around • provides an understanding
with the client again. This repetitive process of functionality
continues until the product meets the critical
mass of business needs or for an agreed
number of iterations.

• takes time to build
• more costly to build
• false sense of security

10. Facilitated sessions

in a facilitated session, you bring a larger
group (five or more) together for a common
purpose. In this case, you are trying to gather
a set of common requirements from the group ▪ Less Time
in a faster manner than if you were to ▪ Reach Group Of People
interview each of them separately. • Brainstorming sessions
(virtual or face-to-face)

• More Expensive
• need for extra facilities
to allow for group work
etc
• Handouts, readings

n..■•■Aite— – – _

11. Joined Application Development

12. Questionnaire

Questionnaires are much more informal, and

they are good tools to gather requirements

from stakeholders in remote locations or

those who will have only minor input into the • Less cost

overall requirements. Questionnaires can also • Reach Large No of People-,

be used when you have to gather input from • The responses are gathered

dozens, hundreds, or thousands of people. in a standardized way

Nc-
MOW 13.0011Wri rillgrAWOC TO1 n PFOIPIA %ISO UM AS.- x,,,,
4.11. NM imry No sa al
mipmmr Li imp…1=1 mr.iss.
❑ 0 0 0
Q 0 0 0 • Difficult filling for users
0 0 ❑ ❑
0 0 ❑ ❑ • participants may forget
❑ 0 ❑ ❑
0 0 ❑ ❑ important issues
❑ 0 ❑ ❑
❑ ❑ ❑ 0 • Stockholders may not be
0 0 0 0 willing to answer the
0 0 0 0
D 0 0 0 questions
0 ❑ ❑ 0
0 0 0 0

13. Survey

When gathering information from many

people: to many to interview with time

constraints and less budget: a questionnaire s Less cost
survey can be used. The survey insists the * Reach Large No of
users to choose from the given options agree Peoples
disagree or rate something. Do not think that
* A detailed critical
you can make a survey on your own but try to inspection
add meaningful insight in it. A well designed
survey must give qualitative guidance for

characterizing the market. It should not be

utilized for prioritizing of requirements or
features. * Difficult filling for users

▪ participants may forget
important issues

* Stockholders may not be
willing to answer the
questions

Difference between questionnaire

and survey?

The Oxford dictionary defines them as quoted below:

sumer
1 aiming view, cominatkm. or clescrilptkin. a an imrestiiptkm of the
opinions or =pajama of a group of pnde, based on a. series of iwinii:icm
an act of sunning. 4 a map or report obtained by surveying.

(mmtkonnaire:
noun a set of primmd questioru4 usual4rwiti h a comae &answers, devised for a survey or stitbolud. study.
a survey or stitbolud. study.

14. Use cases and scenarios

Use cases are basically stories that describe

how discrete processes work. The stories

include people (actors) and describe how the
• provide the best return on

solution works from a user perspective. Use invested effort

cases may be easier for the users to articulate. • explain how that system will

although the use cases may need to be be implemented

distilled later into the more specific detailed • Each use case provides a set

requirements. of scenarios that convey how

the system should interact

A..

tom. • Poor identification of

1..poirww. 4….muir.• structure and flow
olhpr.r. .
11411vadoe
• Time-consuming to generate

• Scenario management is

difficult

15. Reused Requirement

In the field of software engineering
reusing the requirements of the
existing system is common method of
requirements elicitation. Using the • Reused requirements
existing knowledge to develop the are already validated
new product has many advantages and analyzed thus
that include low cost and less time. reducing the time of
Though each product has their own testing
type of stake holders and users, there
is still number of situations that theRisks & Drawbacks
reusing of the requirements take
places • Some time proposed
product is completely
different form the
existing product

Thank You!
04.05.2025
CSS Learning Tutorial P001
CSS Learning Tutorial P001

What is CSS?
- CSS stands for Cascading Style Sheets
- CSS describes how HTML elements are to be displayed on screen, paper, or in other media
- CSS saves a lot of work. It can control the layout of multiple web pages all at once
- External stylesheets are stored in CSS files
CSS Comments

Comments are used to explain the code, and may help when you edit the source code at a later date.

Comments are ignored by browsers.

A CSS comment is placed inside the <style> element, and starts with /* and ends with */

CSS Padding

The CSS padding properties are used to generate space around an element’s content, inside of any defined borders.

With CSS, you have full control over the padding. There are properties for setting the padding for each side of an element (top, right, bottom, and left).

Padding – Individual Sides

CSS has properties for specifying the padding for each side of an element:
- padding-top
- padding-right
- padding-bottom
- padding-left
CSS Setting height and width

The height and width properties are used to set the height and width of an element.

The height and width properties do not include padding, borders, or margins. It sets the height/width of the area inside the padding, border, and margin of the element.

CSS height and width Values

The height and width properties may have the following values:
- auto – This is default. The browser calculates the height and width
- length – Defines the height/width in px, cm, etc.
- % – Defines the height/width in percent of the containing block
- initial – Sets the height/width to its default value
- inherit – The height/width will be inherited from its parent value
The four links states are:
- a:link – a normal, unvisited link
- a:visited – a link the user has visited
- a:hover – a link when the user mouses over it
- a:active – a link the moment it is clicked
Block-level Elements

A block-level element ALWAYS starts on a new line and takes up the full width available (stretches out to the left and right as far as it can).

The <div> element is a block-level element.

Examples of block-level elements:
- <div>
- <h1> – <h6>
- <p>
- <form>
- <header>
- <footer>
- <section>
Inline Elements

An inline element DOES NOT start on a new line and only takes up as much width as necessary.

This is an inline <span> element inside a paragraph.

Examples of inline elements:
- <span>
- <a>
- <img>
The position Property

The position property specifies the type of positioning method used for an element.

There are five different position values:
- static
- relative
- fixed
- absolute
- sticky
Elements are then positioned using the top, bottom, left, and right properties. However, these properties will not work unless the position property is set first. They also work differently depending on the position value.

The z-index Property

When elements are positioned, they can overlap other elements.

The z-index property specifies the stack order of an element (which element should be placed in front of, or behind, the others).

The float Property

The float property is used for positioning and formatting content e.g. let an image float left to the text in a container.

The float property can have one of the following values:
- left – The element floats to the left of its container
- right – The element floats to the right of its container
- none – The element does not float (will be displayed just where it occurs in the text). This is default
- inherit – The element inherits the float value of its parent
04.05.2025

Abstraction in Java | OOP Fundamental Concept

Ways to achieve Abstraction
- 1. Abstract Classes and Abstract Methods
- 2. Interface
Advantage of Abstraction

Topic – 1 : Abstraction

Abstraction is a process of hiding the implementation details and showing only functionality to the user.

Another way, it shows only essential things to the user and hides the internal details, for example, sending SMS where you type the text and send the message. You don’t know the internal processing about the message

An Abstraction is a process of exposing all the necessary details and hiding the rest. In Java, Data Abstraction is defined as the process of reducing the object to its essence so that only the necessary characteristics are exposed to the users.

Ways to achieve Abstraction

There are two ways to achieve abstraction in java

Abstract class (0 to 100%)
Interface (100%)

In Java, we can achieve Data Abstraction using Abstract classes and interfaces.

Interfaces allow 100% abstraction (complete abstraction). Interfaces allow you to abstract the implementation completely.
Abstract classes allow 0 to 100% abstraction (partial to complete abstraction) because abstract classes can contain concrete methods that have the implementation which results in a partial abstraction.

Abstract Class

A class which is declared as abstract is known as an abstract class.
An Abstract class is created through the use of the abstract keyword.
It is used to represent a
Object Can not be created of an Abstract
Does not Support multiple inheritance.

Points to Remember

An abstract class must be declared with an abstract
It can have abstract and non-abstract methods.
The class has to be declared as abstract if it contains at least one abstract
It can have constructors, static methods and final methods.
It can have any type of variables (Static, non-static, final, non-final etc)

Syntax of declaring an abstract class:

To declare an abstract class we use the keyword The syntax is given below:

access-specifier abstract class ClassName

{

//class body

}

Abstract Methods in Java

• A method which is declared as abstract and does not have implementation is known as an abstract method.

The declaration of an abstract method must end with a semicolon ;

• The child classes which inherit the abstract class must provide the implementation of these inherited abstract methods.

Syntax of declaring abstract methods:

access-specifier abstract return-type method_name();

Example:

public abstract void printStatus();

Example – 1

public void move(){System.out.println(“Car moves faster.”);}

public class Car extends Vehicle {

public abstract class Vehicle { public abstract void move();}

An abstract class that has abstract method

Example – 2
An abstract class that has abstract , non-abstract methods and Constructor
	public abstract class Vehicle {	public class Car extends Vehicle {
	public Vehicle(){System.out.println(“Vehicle is Created.”);}	public void move(){System.out.println(“Car moves faster.”);}
	public abstract void move(); public void carry(){System.out.println(“All Vehicle carry loads”);}	public static void main(String[] args) { Car c1 = new Car();c1.move();c1.carry();}}
	}	// Outputs:Vehicle is Created. Car moves faster.All Vehicle carry loads

Interface in Java

An interface is a blueprint or template of a class.
It is much similar to the class but the only difference is that it has abstract methods and

static constants.

Object can not be created of an
All the methods in an interface are by default abstract.
All variables are declared as both static and
An interface does not contain any constructors.
An interface can not be extended or inherited by a class; it is implemented by a
Multiple-Inheritance supported.

Internal addition by the compiler

Syntax of declaring an Interface

interface <interface_name>{

// declare constant fields

// declare methods that abstract

//by default.

}

The relationship between classes and interfaces

As shown in the figure given below, a class extends another class, an interface extends another interface, but a class implements an interface

Example – 1

public class SIBL implements Bank{ public double account (){System.out.println(“Account System in SIBL”);}}

class TestInterface{public static void main(String[] args){SIBL b=new SIBL();b. account ();DBBL d=new DBBL();d. account ();}}

interface Bank{ double account();}

public class DBBL implements Bank{ public double account (){System.out.println(“Account System in DBBL”);}}

Multiple inheritance in Java by interface

If a class implements multiple interfaces, or an interface extends multiple interfaces, it is known as

multiple inheritance

Example – 2

interface FirstInterface { public void myMethod();}

class DemoClass implements FirstInterface, SecondInterface {

public void myMethod() {

System.out.println(“Some text..”);

}

interface SecondInterface {public void myOtherMethod();}

Thank you!

04.05.2025

File Handling in C Programming
1. Opening a File: fopen()

To work with files in C, the fopen() function is used to open a file. It takes two parameters: the file name and the mode of operation (e.g., read, write, append).

FILE *filePointer = fopen(“filename.txt”, “mode”);

File Modes:
- “r”: Opens a file for reading (fails if the file doesn’t exist).
- `”w”`: Opens a file for writing (creates a new file or truncates an existing one).
- `”a”`: Opens a file for appending (writes data at the end).
- `”r+”`: Opens a file for both reading and
2. Closing a File: fclose()

After operations are done, the file should be closed using the `fclose()` function to free the resources.

fclose(filePointer);

3. Reading from a File: fscanf(), fgets(), and fgetc()
- fscanf(): Similar to scanf(), but for
fscanf(filePointer, “%d”, &var);
- fgets(): Reads a line from the file, ideal for reading
fgets(buffer, size, filePointer);
- fgetc(): Reads a single character from the
char ch = fgetc(filePointer);

4. Writing to a File: fprintf(), fputs(), and fputc()
- fprintf(): Similar to printf(), but writes to a
fprintf(filePointer, “Data: %d”, value);
- fputs(): Writes a string to a
fputs(“Hello, World!”, filePointer);
- fputc(): Writes a single character to a
fputc(‘A’, filePointer);

5. Checking for End-of-File (EOF): feof()

The feof() function checks if the end of the file is reached.

if (feof(filePointer)) {

printf(“End of file reached.\n”);

}

7. File Positioning: ftell(), fseek(), and rewind()
- ftell(): Returns the current position in the
long position = ftell(filePointer);
- fseek(): Moves the file pointer to a specific
fseek(filePointer, offset, SEEK_SET);
- SEEK_SET: Beginning of the
- SEEK_CUR: Current
- SEEK_END: End of the
- rewind(): Moves the file pointer back to the
rewind(filePointer);

8. Binary File Operations: fread() and fwrite()

Binary files store data in binary format (unlike text files). To handle binary files, C provides:
- fread(): Reads binary data from a
fread(buffer, size, count, filePointer);
- fwrite(): Writes binary data to a
fwrite(buffer, size, count, filePointer);

9. Error Handling: perror() and ferror()
- perror(): Displays an error message if file operations
perror(“Error opening file”);
- ferror(): Checks if an error occurred during a file
if (ferror(filePointer)) { printf(“Error reading file.\n”);

}

10. Removing and Renaming Files
- remove(): Deletes a
remove(“filename.txt”);
- rename(): Renames a
rename(“oldname.txt”, “newname.txt”);

Code 1: #include<stdio.h> int main()

{

FILE *fp;

char filename[]=”my_file.txt”;

fp=fopen(filename,”w”);

fprintf(fp,”We are learning file operations in c\n”); fprintf(fp,”Hello People\n”);

fclose(fp);

fp=fopen(filename,”a”); fprintf(fp,”Hello World\n”);

return 0;

}

Code 2:

//Writing to a file #include <stdio.h> #include <stdlib.h>

int main()

{

struct student

{

int age;

char name[30]; int CGPA;

}student1;

FILE *fptr;

// use appropriate location if you are using MacOS or Linux fptr = fopen(“program.txt”,”w”);

if(fptr == NULL)

{

printf(“Error!”); exit(1);

}

printf(“Enter Student’s name: “); scanf(“%s”,&student1.name);

printf(“Enter Student’s age: “); scanf(“%d”,&student1.age);

printf(“Enter Student’s CGPA: “); scanf(“%d”,&student1.CGPA);

fprintf(fptr,”%s\t %d\t %d\t”,student1.name,student1.age,student1.CGPA); fclose(fptr);

return 0;

}

Code 3:

//reading from a file #include <stdio.h> #include <stdlib.h>

int main()

{

char name[30];

char input_name[30]; int cmp_result;

FILE *fptr;

if ((fptr = fopen(“program.txt”,”r”)) == NULL){ printf(“Error! opening file”);

// Program exits if the file pointer returns NULL. exit(1);

}

scanf(“%s”,input_name); fscanf(fptr,”%s”, &name);

cmp_result=strcmp(input_name,name);

printf(“Value of comparing result is =%d”, cmp_result);

fclose(fptr);

return 0;

}

Code 4:

#include<stdio.h> struct student

{

int rollno;

char name[30]; float mark;

}stud;

//    FUNCTION TO INSERT RECORDS TO THE FILE

void insert()

{

FILE *fp;

fp = fopen(“Record.txt”, “a”); printf(“Enter the Roll no :”); scanf(“%d”, &stud.rollno); printf(“Enter the Name      :”); scanf(“%s”, &stud.name); printf(“Enter the mark                                         :”); scanf(“%f”, &stud.mark);

//fwrite(&stud, sizeof(stud), 1, fp);

fprintf(fp,”%d %s %.1f\n”,stud.rollno,stud.name,stud.mark); fclose(fp);

}

//    FUNCTION TO DISPLAY RECORDS

void disp()

{

FILE *fp1;

fp1 = fopen(“Record.txt”, “r”); printf(“\nRoll Number\tName\tMark\n\n”); while (fread(&stud, sizeof(stud), 1, fp1))

printf(” %d\t\t%s\t%.2f\n”, stud.rollno, stud.name, stud.mark); fclose(fp1);

}

//    FUNCTION TO SEARCH THE GIVEN RECORD

void search()

{

FILE *fp2; int r, s, avl;

printf(“\nEnter the Roll no you want to search :”); scanf(“%d”, &r);

avl = avlrollno(r); if (avl == 0)

printf(“Roll No %d is not available in the file\n”,r); else

{

fp2 = fopen(“Record.txt”, “r”);

while (fread(&stud, sizeof(stud), 1, fp2))

{

s = stud.rollno; if (s == r)

{

printf(“\nRoll no = %d”, stud.rollno); printf(“\nName                            = %s”, stud.name); printf(“\nMark                          = %.2f\n”, stud.mark);

}

}

fclose(fp2);

}

}

//    FUNCTION TO DELETE A RECORD

void deletefile()

{

FILE *fpo; FILE *fpt; int r, s;

printf(“Enter the Roll no you want to delete :”); scanf(“%d”, &r);

if (avlrollno(r) == 0)

printf(“Roll no %d is not available in the file\n”, r); else

{

fpo = fopen(“Record.txt”, “r”); fpt = fopen(“TempFile.txt”, “w”);

while (fread(&stud, sizeof(stud), 1, fpo))

{

s = stud.rollno; if (s != r)

fwrite(&stud, sizeof(stud), 1, fpt);

}

fclose(fpo); fclose(fpt);

fpo = fopen(“Record.txt”, “w”); fpt = fopen(“TempFile.txt”, “r”);

while (fread(&stud, sizeof(stud), 1, fpt)) fwrite(&stud, sizeof(stud), 1, fpo); printf(“\nRECORD DELETED\n”); fclose(fpo);

fclose(fpt);

}

}

//    FUNCTION TO UPDATE THE RECORD

void update()

{

int avl; FILE *fpt; FILE *fpo; int s, r, ch;

printf(“Enter roll number to update:”); scanf(“%d”, &r);

avl = avlrollno(r); if (avl == 0)

{

printf(“Roll number %d is not Available in the file”, r);

}

else

{

fpo = fopen(“Record.txt”, “r”); fpt = fopen(“TempFile.txt”, “w”);

while (fread(&stud, sizeof(stud), 1, fpo))

{

s = stud.rollno; if (s != r)

fwrite(&stud, sizeof(stud), 1, fpt); else

{

printf(“\n\t1. Update Name of Roll Number %d”, r); printf(“\n\t2. Update Mark of Roll Number %d”, r);

printf(“\n\t3. Update both Name and Mark of Roll Number %d”, r); printf(“\nEnter your choice:”);

scanf(“%d”, &ch); switch (ch)

{

case 1:

printf(“Enter Name:”); scanf(“%s”, &stud.name); break;

case 2:

printf(“Enter Mark : “); scanf(“%f”, &stud.mark); break;

case 3:

printf(“Enter Name: “); scanf(“%s”, &stud.name); printf(“Enter Mark: “); scanf(“%f”, &stud.mark); break;

default:

printf(“Invalid Selection”); break;

}

fwrite(&stud, sizeof(stud), 1, fpt);

}

}

fclose(fpo); fclose(fpt);

fpo = fopen(“Record.txt”, “w”); fpt = fopen(“TempFile.txt”, “r”);

while (fread(&stud, sizeof(stud), 1, fpt))

{

fwrite(&stud, sizeof(stud), 1, fpo);

}

fclose(fpo); fclose(fpt);

printf(“RECORD UPDATED”);

}

}

/* FUNCTION TO SORT THE RECORD */

void sort()

{

int a[20], count = 0, i, j, t, c; FILE *fpo;

fpo = fopen(“Record.txt”, “r”);

while (fread(&stud, sizeof(stud), 1, fpo))

{

a[count] = stud.rollno; count++;

}

c = count;

for (i = 0; i<count – 1; i++)

{

for (j = i + 1; j<count; j++)

{

if (a[i]>a[j])

{

t = a[i]; a[i] = a[j]; a[j] = t;

}

}

}

printf(“Roll No.\tName\t\tMark\n\n”); count = c;

for (i = 0; i<count; i++)

{

rewind(fpo);

while (fread(&stud, sizeof(stud), 1, fpo))

{

if (a[i] == stud.rollno)

printf(“\n %d\t\t %s \t\t %2f”,stud.rollno, stud.name, stud.mark);

}

}

}

//    FUNCTION TO CHECK GIVEN ROLL NO IS AVAILABLE //

int avlrollno(int rno)

{

FILE *fp; int c = 0;

fp = fopen(“Record.txt”, “r”); while (!feof(fp))

{

fread(&stud, sizeof(stud), 1, fp);

if (rno == stud.rollno)

{

fclose(fp); return 1;

}

}

fclose(fp); return 0;

}

//FUNCTION TO CHECK THE FILE IS EMPTY OR NOT

int empty()

{

int c = 0; FILE *fp;

fp = fopen(“Record.txt”, “r”);

while (fread(&stud, sizeof(stud), 1, fp)) c = 1;

fclose(fp); return c;

}

// MAIN PROGRAM

void main()

{

int c, emp; do

{

printf(“\n\t—Select your choice——– \n”);

printf(“\n\t1. INSERT\n\t2. DISPLAY\n\t3. SEARCH”); printf(“\n\t4. DELETE\n\t5. UPDATE\n\t6. SORT”); printf(“\n\t7. EXIT”);

printf(“\n\n                                                   \n”);

printf(“\nEnter your choice:”); scanf(“%d”, &c);

printf(“\n”);

switch (c)

{

case 1:

insert(); break; case 2:

emp = empty(); if (emp == 0)

printf(“\nThe file is EMPTY\n”); else

disp(); break; case 3:

search(); break; case 4:

deletefile(); break;

case 5:

update(); break; case 6:

emp = empty(); if (emp == 0)

printf(“\n The file is EMPTY\n”); else

sort(); break; case 7: exit(1);

break; default:

printf(“\nYour choice is wrong\nPlease try again…\n”); break;

}

} while (c != 7);

}

Code 5:

// C program to illustrate fgetc() function

//fgetc() is used to obtain input from a file single character at a time. #include <stdio.h>

int main ()

{

// open the file

FILE *fp = fopen(“test.txt”,”r”);

// Return if could not open file if (fp == NULL)

return 0;

do

{

// Taking input single character at a time char c = fgetc(fp);

// Checking for end of file if (feof(fp))

break ;

printf(“%c”, c);

} while(1);

fclose(fp); return(0);

}

Code 6:

// C program to illustrate fputc() function #include<stdio.h>

int main()

{

int i = 0;

FILE *fp = fopen(“output.txt”,”w”);

// Return if could not open file if (fp == NULL)

return 0;

char string[] = “good bye”, received_string[20];

for (i = 0; string[i]!=’\0′; i++)

// Input string into the file

// single character at a time fputc(string[i], fp);

fclose(fp);

fp = fopen(“output.txt”,”r”);

// Reading the string from file fgets(received_string,20,fp);

printf(“%s”, received_string);

fclose(fp); return 0;

}
04.05.2025
Dynamic Memory Allocation in C using malloc

Dynamic Memory Allocation in C using malloc

Defined the topics:
1. Malloc
2.Calloc
3.Realloc

Every team will make report on the given topics in details and submit here. As this is a teamwork, group
members will work on one report.
1. Function of malloc(), calloc(),realloc()
2. Syntax of these 3 methods (With Explanation)
3. Apply these methods in code and explain.
4.Advantage, Disadvantage.

Answer:

1. Functions of malloc(), calloc(), and realloc()
 malloc():
Allocates a specified amount of memory during runtime and returns a pointer to the first byte of the
allocated memory. The memory is uninitialized.
 calloc():
Allocates memory for an array of elements, initializes all bytes to zero, and returns a pointer to the
allocated memory.
 realloc():
Changes the size of previously allocated memory block. It can be used to increase or decrease the
size of the memory allocated and may move the memory to a new location if necessary.

2. Syntax of These Methods
 malloc(size_t size)
Description: Allocates size bytes of memory.
Return Value: Returns a pointer to the allocated memory or NULL if the allocation fails.
 calloc(size_t num, size_t size)
Description: Allocates memory for an array of num elements, each of size bytes.
Return Value: Returns a pointer to the allocated memory or NULL if the allocation fails.
 realloc(void *ptr, size_t size)
Description: Resizes the memory block pointed to by ptr to size bytes. If ptr is NULL, it
behaves like malloc.
Return Value: Returns a pointer to the newly allocated memory or NULL if the allocation
fails. The original memory block is freed if the allocation fails.

3. Apply These Methods in Code
#include <stdio.h>
#include <stdlib.h>
int main() {
int *arr1;
arr1 = (int*)malloc(5 * sizeof(int));
if (arr1 == NULL) {
printf(“Memory allocation failed\n”);
return 1;
}
int *arr2;
arr2 = (int*)calloc(5, sizeof(int));
if (arr2 == NULL) {
printf(“Memory allocation failed\n”);
free(arr1);
return 1;
}
arr1 = (int*)realloc(arr1, 10 * sizeof(int)); // Resize to hold 10 integers
if (arr1 == NULL) {
printf(“Reallocation failed\n”);
free(arr2);
return 1;
}
free(arr1);
free(arr2);
return 0;
}

4. Advantages and Disadvantages
 malloc()
Advantages: Simple to use; allocates a specific amount of memory.
Disadvantages: Memory is uninitialized, which can lead to unpredictable behavior if accessed before initialization.
 calloc()
Advantages: Initializes allocated memory to zero, which can prevent issues with uninitialized data.
Disadvantages: Slightly slower than malloc() due to initialization.
 realloc()
Advantages: Allows dynamic resizing of memory, which can be more memory-efficient.
Disadvantages: May involve moving memory to a new location, which requires additional overhead; can lead to memory leaks if not handled properly.

04.05.2025

Software Engineering Course List

Level – 01, Term – 01 (01 Semester)

SI No	Code	Course Title	Pre-requisite	Category	Credit
01	SE 111	Computer Fundamentals		Core	3
02	SE 112	Computer Fundamentals Lab		Lab	1
03	SE 113	Introduction to Software Engineering		Core	3
04	ENG 114ENG 101	English Reading, Writing Skills & Public Speaking / English I		GED	3
05	AOL 101	Art of Living		GED	3
06	MAT 124MAT 101	Math-I: Calculus & Geometry/ Mathematics I		GED	3
				Total	16

Level – 01, Term – 02 (02 Semester)

SI No	Code	Course Title	Pre-Requisite	Category	Credit
01	SE 121	Structured Programming	SE 111SE 112	Core	3
02	SE 122	Structured Programming Lab	SE 111SE 112	Lab	1
03	SE 123	Discrete Mathematics		PGC	3
04	SE 212	Software Requirement Specifications & Analysis	SE 113	Core	3
05	SE 213	Digital Electronics & Logic Design	SE 111SE112	PGC	3
06	PHY 125PHY 101	Physics: Mechanics, Electromagnetism & Waves / Physics I		GED	3
07	MAT 134MAT 102	Math-II: Linear Algebra & Fourier Analysis / Mathematics II	MAT124MAT101	GED	3
				Total	19

Level – 02, Term – 01 (03 Semester)

SI No	Code	Course Title	Pre-Requisite	Category	Credit
01	SE 131	Data Structure	SE 121SE 122SE 123	PGC	3
02	SE 132	Data Structure Lab	SE 121SE 122SE 123	Lab	1
03	SE 133	Software Development Capstone Project	SE 121SE 122	Lab-P	3
04	SE 211	Object Oriented Concepts	SE 121SE 122	Core	3
05	SE 222	Computer Architecture	SE 213	PGC	3
06	STA 135STA 101	Probability & Statistics in Software Engineering / Statistics I		GED	3
07	BNS 101	Bangladesh Studies		GED	3
				Total	19

Level – 02, Term – 02 (04 Semester)

SI No	Code	Course Title	Pre-Requisite	Category	Credit
01	SE 214	Algorithms Design & Analysis	SE 131SE 132	PGC	3
02	SE 215	Algorithms Design & Analysis Lab	SE 131SE 132	Lab	1
03	SE 221	Object Oriented Design	SE211	Core	3
04	SE 223	Database System		Core	3
05	SE 224	Database System Lab		Lab	1
06	SE 232	Operating System & System Programming	SE 222	PGC	3
07	SE 233	Operating System & System Programming Lab	SE 222	Lab	1
08	GE 235	Principles of Accounting, Business & Economics		GED	3
09	SE 532SE XXX	Introduction to Robotics (G-1) / Guided Elective- I	SE 213	PGC	3
				Total	21

Level – 03, Term – 01 (05 Semester)

SI No	Code	Course Title	Pre-Requisite	Category	Credit
01	SE 225	Data Communication & Computer Networking		PGC	3
02	SE 226	Data Communication & Computer Networking Lab		Lab	1
03	SE 231	System Analysis & Design Capstone Project	SE 133SE 212SE 221	Lab-P	3
04	SE 234	Theory of Computing		PGC	3
05	SE 311	Design Pattern	SE 221	Core	3
06	SE 312	Software Quality Assurance & Testing	SE 212SE 221	Core	3
07	SE 313	Software Quality Assurance & Testing Lab	SE 212SE 221	Lab	1
08	GE 324	Business Analysis & Communication	ENG114ENG101SE212	GED	3
				Total	20

Level – 03, Term – 02 (06 Semester)

SI No	Code	Course Title	Pre-Requisite	Category	Credit
01	SE 321	Software Engineering Web Application	SE 121SE 122	Core	3
02	SE 322	Software Engineering Web Application Lab	SE 121SE 122	Lab	1
03	SE 323	Software Architecture & Design	SE212, SE221SE223, SE311	Core	3
04	SE 332	Information System Security		Core	3
05	SE 411	Software Project Management & Documentation	SE 312	Core	3
06	SE 333	Artificial Intelligence	SE 214, SE 234	Core	3
07	SE 334	Artificial Intelligence Lab	SE 214, SE 234	Lab	1
08	SE 544SE XXX	Introduction to Machine Learning (G -2) Guided Elective – I I	MAT 101MAT 102,STA 101, SE 121	PGC	3
				Total	20