23 results for: alessiomungelli
A Java approach: While loop
Hello everyone and welcome back! After having made a short, but full-bodied, introduction about cycles, today we are finally going to see the first implementations that use what we have called preconditional cycle. In Java, as in many other programming languages, this type of cycle is translated with the term while, which…
Category : Java 25-10-2020 by Alessio Mungelli
A Java approach: The Cycles - Introduction
Hello everyone and welcome back! Until now, we have been talking about variables and selection structures, going to consider some of the fundamental aspects of these two concepts. Theoretically, to write any kind of program, the notions seen so far might be sufficient. However, a problem arises. How can we…
Category : Java 23-10-2020 by Alessio Mungelli
A Java Approach: Selection Structures - Use Cases
Hello everyone and welcome back! Up to now we have been concerned to make as complete an overview as possible of the fundamental concepts we need to approach the use of conditional structures. We have therefore introduced the concept of conditional structures, outlining the various situations that could arise. We…
Category : Java 20-10-2020 by Alessio Mungelli
A Java approach: boolean variables
The previous time, we talked extensively about Boolean variables, trying to outline the main operations that can be carried out at a practical level. Of all the cases examined, we have not examined the most important and most recurrent one: the case in which the conditions to be examined are more…
Category : Java 18-10-2020 by Alessio Mungelli
A Java approach: conditional structures
Hello everyone and welcome back! The previous times we have introduced the concept of variable, trying to define some basic concepts about it. However, some situations suggest that the concept of variable alone is not enough to solve all the possible situations that may arise in front of us. A very…
Category : Java 03-04-2023 by Alessio Mungelli
Hashmap: hashing, collisions and first functions
Today we are going to study some concepts closely related to hashmaps. The concepts we are going to see are hashing and collisions. Hashing The idea of hashing with chaining is to create a sort of array of lists, into which the elements are somehow inserted. We need to map the keys to…
Category : C language 28-06-2020 by Alessio Mungelli
Hashmap: Overflow Lists
In this short series of articles we will go to see how it is possible to create the Hashmap data structure in C. In the implementation we're going to use the doubly concatenated lists as auxiliary data structures. Let's look at a possible implementation. Header file Let's first have a look to what…
Category : C language 18-06-2020 by Alessio Mungelli
Data structures in Java - Linked Lists
With 2020 we are going to look at a new aspect of programming: data structures. It is often the case that everyone uses structures provided by the various programming languages. The objective will be to have a general idea of how they work and their internal mechanisms. Often we will…
Category : Java 22-10-2020 by Alessio Mungelli
A Java approach: variables - use case
Hello all friends and welcome back! After the introduction made on the variables, we try to analyse some critical issues that may arise in quite common situations. Let's start by analysing some practical examples. Example 1: division that returns a non-integer result The first critical case that might arise for those who approach…
Category : Java 22-10-2020 by Alessio Mungelli
A Java approach: variables
Hello everyone and welcome back! Today we will begin a journey that will lead us to study, and possibly review, what are the basics of programming. We will start by talking about variaibli. Introduction Anyone who wants to approach the world of programming will soon realise that coding is not exactly like what…
Category : Java 20-09-2020 by Alessio Mungelli
Linux For Dummies: Permissions
In the previous articles I made a short introduction to the Unix world and in the following article I have dealt with the basic commands for the file system management. Today we are going to talk about permissions. We are going to take Ubuntu as an example, but in the other distros the working mechanism…
Category : Operating systems 14-03-2020 by Alessio Mungelli
Linux for Dummies: Ubuntu Terminal
I introduced in the previous article, available here, the basic concepts concerning the Linux world. Today we are going to have a look to some basic operations that we can perform using the terminal in an Ubuntu-like operating system. What is the command line? Shell, terminal and command line are words that commonly stand for a…
Category : Operating systems 27-02-2020 by Alessio Mungelli
Linux for Dummies: Introduction
If you have thought about migrating from Windows to a Unix operating system, or Linux specifically there are things you should know. The goal is to give essential information (and not) to take the first steps in the world of the "penguin". What is Linux? With the word Linux we commonly refer…
Category : Operating systems 21-08-2020 by Alessio Mungelli
Java Design Pattern: Builder Pattern
Today we are going to talk about a creational pattern that in many situations can represent a useful alternative to the construction of the objects using the constructors: the Builder Pattern. The need to introduce alternative mechanisms to those provided by Java for the creation of objects is originated from the fact…
Category : Java 22-12-2019 by Alessio Mungelli
Java Design Pattern: Strategy Pattern
One of the most popular patterns is the Strategy Pattern. It is also one of the easiest patterns. It is a member of the behavioral patterns family, it has the duty of managing algorithms, relations and responsibility among classes. The GoF defines it as follow: It defines a series of encapsulated algorithms…
Category : Java 13-09-2019 by Alessio Mungelli
Java Sorting Algorithm: Selection Sort
Today we are going to analyze a sorting algorithm that is not very efficient but often used in various fields. We are talking abou the Selection Sort. Let's have a look. Intuition The idea behind it is to divide the array to sort into two sub-arrays: the first that contains the sorted data…
Category : Java 31-03-2023 by Alessio Mungelli
Java Sorting Algorithm: Bubble Sort
Programming, the need to order the collections of data or objects that must then be manipulated often arises. Ordering a list can be useful in cases where you have to do very quick searches. We will see later on how to maintain an ordered list is useful to carry out dichotomous…
Category : Java 15-12-2019 by Alessio Mungelli
Java Sorting Algorithms: Merge Sort
Today we are going to analyze one of the most used sorting algorithms: the Merge Sort. It is part of the Divide and Conquer family, just like the Quick Sort. Merge Sort offers a better performance despite of the Quick Sort since its complexity remains O(n log n) keeping performances. It is also called "algorithm by fusion" The main defect of the Merge…
Category : Java 14-12-2019 by Alessio Mungelli
Java Sorting Algorithms: Quick Sort
Welcome back to this overview about the Java world! Today, we are going to talk about a renowned sorting algorithm: the Quick Sort. The Quick Sort is not very suitable for educational purposes because its implementation may not be trivial, but at the performance level it offers some advantages that are not indifferent, unlike…
Category : Java 14-12-2019 by Alessio Mungelli
Java Design Pattern: Factory Method Pattern
Going on with the speach about design patterns started previously, we are going to talk about another pattern often used: the Factory Method Pattern. The GoF (Gang of Four Design Patterns) defines it in this way: It defines an interface to create objects, but leaves to the subclasses the decision about the…
Category : Java 05-11-2019 by Alessio Mungelli
Java: introduction to Design Patterns and Singleton Pattern
Anyone with even a minimum experience of programming, should have realized that the majority of the problems have common elements. In fact we often find problems with the same pattern but in different contexts. For example, a management software for s supermarket and the one for a great industry will operate…
Category : Java 27-10-2019 by Alessio Mungelli
Java 12, finally less verbose?
We all know Java for its characteristics thanks to which, despite more than 20 years have passed since the first version, it is still one of the most studied and most used languages, despite the growing diffusion of Python. However, one of the biggest flaws is the fact that it is…
Category : Java 10-10-2019 by Alessio Mungelli
Wi-Fi 6
In the second quarter of 2019, Wi-Fi Alliance decided to release the new version of Wi-Fi protocol, innovative already from the name. In fact, if the previous standards had incomprehensible names like IEEE 802.11a, IEEE802.11n and so on, the new protocol is called Wi-Fi 6. This standard introduces some new features.…
Category : Technology 12-09-2019 by Alessio Mungelli
