Notes, summaries, assignments, exams, and exercises for Computer science for University

LibreriaServlet

package servlet;

public class LibreriaServlet extends HttpServlet {

protected void processRequest(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

HttpSession session = request.getSession(false);

Almacen almacen = new Almacen();

List<Libro> librosDisponibles = new ArrayList<Libro>();

try {

librosDisponibles = almacen.consultaLibrosDisponibles();

} catch (Exception e) {

PrintWriter out = response.getWriter();

out.print("ERROR: " + e.getMessage());

out.close();

}

if (session != null) {

String accion = request.getParameter("Accion");

if (accion.equals("agregar"...

OpenCV C Source Code for Image Processing

Below is a complete C program utilizing the OpenCV library to load, display, and process two images using IplImage.

Required Libraries

#include <stdio.h>
#include <stdlib.h>
#include <opencv/cv.h>
#include <opencv/highgui.h>

Main Function and Validation

int main(int argc, char **argv) 
{
    if (argc != 3) // e.g., fruits, birds
    {
        printf("Error: Usage %s image_file_name\n", argv[0]);
        return EXIT_FAILURE;
    }
    // CV_LOAD_IMAGE_COLOR = 1 forces the resultant IplImage to be colour.
    // CV_LOAD_IMAGE_GRAYSCALE = 0 forces a greyscale IplImage.
    // CV_LOAD_IMAGE_UNCHANGED = -1

    // IMG1
    IplImage* Img = cvLoadImage(argv[1], CV_LOAD_IMAGE_UNCHANGED);

Galería de Imágenes que Cambian

HTML

Estructura base

++++++++++++++++++++++++++++++++++++

Árbol binario

Nombre del package: cl.duoc.ded.tree;

Clase Nodo

----------------------------

package cl.duoc.ded.tree;

public class Nodo {
    private int valor;
    private Nodo padre;
    private Nodo hojaIzquierda;
    private Nodo hojaDerecha;
    
    public Nodo (int valor) {
        this.valor = valor;
    }

    public int getValor() {
        return valor;
    }

    public void setValor(int valor) {
        this.valor = valor;
    }

    public Nodo getPadre() {
        return padre;
    }

    public void setPadre(Nodo padre) {
        this.padre = padre;
    }

    public Nodo getHojaIzquierda() {
        return hojaIzquierda;
    }

    public void setHojaIzquierda(Nodo hojaIzquierda)

Aluno Class in Java: Student Management with JDBC

The following Java class, Aluno, represents a student and provides methods to create, read, update and delete records in the aluno table using JDBC.

package classes;

import java.sql.*;
import classes.Conexao;

public class Aluno {

    private int idaluno = 0;
    private String nome = "";
    private String endereco = "";
    private String cidade = "";
    private String estado = "";
    private String pais = "";
    private String cep = "";

    public int getIdaluno() {
        return idaluno;
    }

    public void setIdaluno(int idaluno) {
        this.idaluno = idaluno;
    }

    public String getNome() {
        return nome;
    }

    public void setNome(String nome) {
        this.

Sequential Circuits

A sequential circuit is a system where outputs at a specific instant are a function of the inputs at that instant and the current state of the circuit; essentially, they store information. A sequential system consists of two distinct blocks: a combinational system to process information and a memory system to store it. Generally, feedback circuits are present in these systems.

Memory Elements: Latches and Flip-Flops

Information is stored in binary format. The basic memory elements are latches and flip-flops, which store a single bit of information. These are elementary logical circuits that remain in one of two possible states (Q=0 or Q=1) and switch between them based on triggering inputs.

Classification of Sequential Circuits

By

Operating System Networking

Network software is installed on each computer to enable communication with others.

Services Performed

• File support
• Communications
• Service P / support team

Server Operating System Management

Managing a server in an easy and safe manner is essential for anyone whose professional work involves managing a computer system.

Composition of the Operating System

• Core: This module is the lowest level of an OS. It lies directly on the computer hardware.
• Memory Manager: This module is responsible for absorbing certain portions of main memory for the various programs or program parts that need it.
• System Input / Output: This component presents the user with the I/O data from the device as a separate issue.
• Admin Archives: Responsible for

What is an Algorithm?

An algorithm is formally defined as a finite sequence of steps that lead to the execution of a specific task. Common examples include the basic operations of arithmetic—addition, multiplication, division, and subtraction—performed on real decimal numbers.

Core Characteristics of Algorithms

An algorithm must possess four essential characteristics:

• Finite: It must eventually come to an end.
• Definite: Each step must be precisely defined.
• Inputs: It receives zero or more quantities from the outside.
• Outputs: It produces at least one result.

Forms of Representation

Algorithms can be represented through various methods:

• Narrative Description: Using natural language.
• Flowchart: A conventional graphical representation.
• Pseudocode: Also

Fuzzy Logic

Fuzzy logic extends Boolean logic, allowing intermediate values between TRUE (1) and FALSE (0), such as MAYBE (0.5). A fuzzy logic value can be any value within the range of 0 to 1. This logic incorporates statistical concepts, especially in inference. Fuzzy logic implementations enable control devices to handle indeterminate states, allowing for the evaluation of non-quantifiable concepts. Practical examples include evaluating temperature (hot, warm, medium), happiness (bright, happy, apathetic, sad), and the veracity of an argument (absolutely right, right, counter-argumentative, inconsistent, false, totally wrong).

Fuzzy logic is a research area focused on uncertainty treatment and a family of mathematical models dedicated to...

Cisco Device Access and Security Passwords

• Console Password: Provides limited access for devices via the console connection.
• Enable Password: Restricts access to the privileged EXEC mode.
• Enable Secret Password: An encrypted password restricting access to the privileged EXEC mode.
• VTY Password: Limits access to devices using Telnet.

Basic Configuration Command Examples

Console Access Configuration

Switch(config)# line console 0
Switch(config-line)# password password
Switch(config-line)# login

Virtual Terminal (VTY) Access

Router(config)# line vty 0 4
Router(config-line)# password password
Router(config-line)# login

Banner Message of the Day

Switch(config)# banner motd # message #

Interface IP Address Assignment

Router(config)# interface FastEthernet 0/0
Router(