Notes, summaries, assignments, exams, and problems for Computer science

Data Structures and Algorithms Practice Problems

Computer science338.98 KB

Q1. Array Address Calculation (Row & Column Major)

Problem: An array ARR[-5...15, 10...20] stores elements in Row Major with each element requiring 2 bytes. Base address is 2500. Find the address of ARR[10][15].

Answer:

  • Row range: -5 to 15, so Lr = -5, Ur = 15
  • Column range: 10 to 20, so Lc = 10, Uc = 20
  • Element size (w) = 2 bytes
  • Base Address (BA) = 2500

Step 1: Calculate dimensions

  • Number of rows (M) = Ur - Lr + 1 = 15 - (-5) + 1 = 21
  • Number of columns (N) = Uc - Lc + 1 = 20 - 10 + 1 = 11

Step 2: Row Major Order Formula

Address(A[i][j]) = BA + [(i - Lr) × N + (j - Lc)] × w
Address(ARR[10][15]) = 2500 + [(10 - (-5)) × 11 + (15 - 10)] × 2
= 2500 + [15 × 11 + 5] × 2
= 2500 + [165 + 5] × 2
= 2500 + 170 × 2 = 2840

Step 3: Column Major Order Formula

Address(...

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It used to define the member functions of a class outside

Computer science4.48 KB


Features of Java

Java is a popular, high-level programming language known for its simplicity, security, and portability. The major features are:

1. Simple

Java is easy to learn and understand. It removes complex features like pointers, multiple inheritance, and operator overloading found in C/C++.

2. Object-Oriented

Java follows the concepts of OOP such as classes, objects, inheritance, polymorphism, abstraction, and encapsulation, making programs modular and reusable.

3. Platform Independent

Java programs are compiled into bytecode, which can run on any device that has the Java Virtual Machine (JVM). This provides Write Once, Run Anywhere (WORA) capability.

4. Secure

Java provides built-in security through the bytecode verifier, class loader, and security...

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Registro de Películas con Flask y JavaScript

Computer science2.92 KB

Integración de Frontend y Backend para Películas

A continuación, se presenta la implementación técnica para el registro y gestión de películas utilizando JavaScript en el cliente y Flask en el servidor.

Implementación del Cliente con JavaScript

El siguiente bloque de código gestiona la captura de datos del formulario y su envío mediante la Fetch API:

const API_URL = 'http://127.0.0.1:5000';

const formulario = document.getElementById("pelicula_Form");
const tituloInput = document.getElementById("titulo");
const directorInput = document.getElementById("director");
const anioInput = document.getElementById("anio");

formulario.addEventListener("submit", registrar_Pelicula);

async function registrar_Pelicula(event) {
    try {
        const
...
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Linear Algebra: Row Space, Null Space, Determinants, and Gram-Schmidt

Computer science2.02 MB

Finding the Basis of a Row Space

The easiest way to find the basis of a row space is to reduce matrix A to Reduced Row Echelon Form (RREF). The nonzero row vectors of R (which contain the leading 1s, or pivots) form a basis for row(A).

Finding the Basis of the Kernel

The following four steps outline the most effective method for finding a basis for null(A):

  1. Reduce A to RREF (R): Find the Reduced Row Echelon Form (R) of the matrix A.
  2. Solve the Homogeneous System: Use the RREF, R, to solve the equivalent homogeneous system Rx=0.
  3. Identify and Parameterize Variables:
    • Identify the leading variables (those corresponding to columns containing a leading 1 or pivot in the RREF) and the free variables.
    • Solve for the leading variables in terms of the free variables.
...
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Data Mining and Knowledge Discovery: Core Concepts

Computer science1.43 MB

Multilevel Association Rules

Hierarchy Matters: Items in databases are structured from general to specific (e.g., Food → Dairy → Milk → Amul Milk).

Low-Level Items: Rarely appear, so have low support.

Support & Confidence: Support decreases as we get specific; confidence usually stays stable in the hierarchy.

Approaches: Uniform Minimum Support uses the same support for all levels, but may miss specific patterns. Reduced Minimum Support assigns different supports; higher levels get a higher threshold, while lower levels get a smaller threshold.

Search Strategies: Independent Search mines levels separately. Level-Cross Filtering explores child nodes only if the parent is frequent. Controlled Level-Cross Filtering balances exploration and...

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Cloud Machine Learning Workflow and Content Delivery Optimization

Computer science3.81 KB

Steps for Training a Machine Learning Project in the Cloud

Definition: Cloud ML Project Training

Training an ML Project in the Cloud means utilizing cloud-based resources and services to build, train, and optimize a Machine Learning model.

The Seven Key Steps in Cloud ML Training

  1. Data Collection: Gather and upload the dataset to cloud storage.
  2. Data Preprocessing: Clean and prepare data using cloud notebooks or specialized processing services.
  3. Model Selection: Choose the appropriate algorithm or utilize a pre-built model architecture.
  4. Training: Use scalable cloud compute resources (GPUs/TPUs) for intensive model training.
  5. Evaluation: Test model accuracy and performance using validation data.
  6. Hyperparameter Tuning: Optimize model parameters for better
...
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Advanced Web Design and JavaScript Exam Revision Sheet

Computer science3.65 KB

This revision sheet covers essential concepts for Advanced Web Designing and Advanced JavaScript exams, designed for effective last-minute study.


🧠 Advanced Web Design & JavaScript Revision

1. Fill in the Blanks (10 Marks)

  1. HTML stands for HyperText Markup Language.
  2. CSS is used for styling web pages.
  3. The <div> tag is a block-level element.
  4. The <span> tag is an inline element.
  5. External CSS files use the .css extension.
  6. JavaScript is a client-side scripting language.
  7. The <script> tag is used to embed JavaScript code in HTML.
  8. document.write() is used to print content on a web page.
  9. var, let, and const are used to declare variables in JavaScript.
  10. The href attribute is used in the <a> tag to link to another page.

2. True or False

...
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Essential Object-Oriented Programming Concepts Defined

Computer science11.61 KB

Core OOP Definitions

Class and Object

  • Class: A user-defined data structure that binds data members and operations (methods) into a single unit.
  • Object: An instance of a class. Objects are used to perform actions or allow interactions based on the class definition.

Variables and Attributes

  • Method: An action performed using the object's attributes.
  • Attributes: Characteristics or properties of a class. Also known as instance variables (declared outside methods, belonging to one object). They are accessible through static and public methods.
  • Class Variable: Declared using the static keyword; shared among all objects of the class.
  • Local Variables: Declared inside methods, constructors, or blocks; they exist only while the method runs. They cannot be accessed
...
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Web Application Security: Vulnerabilities and Mitigations

Computer science1.73 MB

Web Security Fundamentals

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Common Cross-Site Scripting (XSS) Types

XSS TypeExample PayloadDescription
Reflected XSS<script>alert(1)</script>Injected payload reflected immediately in server response.
Stored XSS<img src="x" onerror="alert(1)">Payload stored on server (e.g., in database), executed later.
DOM-Based XSSURL: #<script>alert(1)</script>Payload executed via client-side JavaScript manipulation.
Event Handler XSS<a onclick="alert(1)">Click</a>Injects event attributes to run JS on user actions.
Attribute Injection"><script>alert(1)</script>Breaks out of HTML attribute to inject malicious code.
JavaScript URI XSS<a href="javascript:alert(1)">Click</a>Runs JS via link clicks
...
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Neural Networks: Core Concepts and Architectures

Computer science161.05 KB

1. What is ANN? What is a Neuron?

Artificial Neural Networks (ANNs) are inspired by the biological neural networks of the human brain. They are a set of algorithms designed to recognize patterns. ANN consists of layers: input layer, hidden layers, and output layer. Each layer is made up of nodes called neurons.

A neuron in ANN is a mathematical function modeled after a biological neuron. It receives one or more inputs, applies a weight and bias to them, sums them up, and passes the result through an activation function to produce output.

ANNs are widely used in tasks like image recognition, natural language processing, and more. They learn from data by adjusting weights using optimization algorithms like gradient descent.

2. What is Optimization

...
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