Skill Improvement Algorithm Coding Test 40-Day Completion (by HaruCoding)

This is a lecture on [Data Structure and Algorithm Core Theory & Related Practical Problem Solving] for IT company coding test preparation. - Python version -

Baekjoon Bronze 4·5 Difficulty Algorithm Beginner Roadmap Starting with 3-4 Problems Daily

Master Algorithm Problem Solving with 100 Essential Silver Level Problems from Baekjoon Online Judge

For IT company coding test preparation, This is a [Data Structures & Algorithms Core Theory & Related Practical Problem Solving Lecture]. - JAVA Edition -

A course on Data Structures & Algorithms core theory & practical problem-solving, for IT company coding test prep. (C++)

Baekjoon Bronze 3 Level Core Problem-Based Coding Test Fundamentals Training

Baekjoon Bronze 4·5 Difficulty Algorithm Beginner Roadmap Starting with 3-4 Problems Daily

Baekjoon Bronze 3 Level Core Problem-Based Coding Test Fundamentals Training

This course is for job seekers and career-changing backend developers preparing for coding tests with JAVA. We clearly identify question types by analyzing 195 actual past exam questions.

Java Programming Based on Object-Oriented Concepts for Computer Science Majors

This is a lecture for people who are starting development for the first time. It's about programming thinking, which should come before development languages or UI frameworks.

The Code Puzzle Clear Challenge is a 4-week intensive training course based on "Learn to Code 1" in Swift Playgrounds, designed to develop "computational thinking" by giving commands to make a computer move as intended. By solving puzzle missions in each session, participants naturally learn to break down problems into smaller steps (decomposition), recognize patterns to organize repetitive rules using for-loops or functions, and make logical judgments to change actions based on specific situations. Beyond simply finding the right answer, participants reach a level where they can explain and refine "why they solved it this way."

This course covers how to set up multi-module projects from scratch using Kotlin and Spring Boot. It proceeds with a hands-on approach, covering everything from the basic concepts of modularization to Gradle configuration, managing dependencies between modules, and actual application development. If you are a beginner or intermediate developer looking to learn the fundamentals and practical application of multi-modules, please refer to this course.

This course is for those preparing for the CosPro Level 1 exam, covering the COS Pro Level 1 sample problems released by the exam organizer, YBM Net Co., Ltd.

Build a scalable real-time event streaming order processing system using Spring Boot 3.x + Kotlin, establishing a Kafka cluster, and leveraging PostgreSQL CDC, Debezium Connect, and Apache Avro schemas.

Knowing design patterns will make it easier to learn not only Spring but also many other technologies and programming languages. It will also help you develop more flexible and reusable object-oriented software.

In this course, you will learn Kotlin syntax, how to safely convert Java projects to Kotlin, and how to code in a Kotlin-like manner. Learn Kotlin based on practical code and use it yourself to enjoy its advantages.

This course is a video lecture that systematically covers the core modern JavaScript syntax essential for learning React.js and Vue.js frontend development. It is structured to help you develop efficient coding skills through ES6+ syntax, latest features, and practical examples that can be directly applied to work and learning.

Refactoring is one of the basic skills that a software engineer should have. This course is designed to explain and practice various code smells and refactoring techniques in a more practical way using IntelliJ and Java.

When learning Swift, the iOS programming language, it can be confusing when multiple concepts appear all at once. That's why I created this course with the principle that "when understanding a new concept, only previously learned concepts should be used." So this course is meticulously designed with a sequential structure between concepts, where only one new concept appears at each stage, and no other unfamiliar concepts appear at all. One concept per minute, 180 concepts total. From the basics of variables and constants to understanding memory structure from a CS perspective, and even the latest syntax for asynchronous processing. In 3 hours, you'll learn 180 core concepts in the designed order.

We present various clean coding techniques.

Learn the essential modern Java technologies of Lambda, Stream, and functional programming with Java, from the basics to the practical level, in depth.

In [Java Practical Project: UI Edition], we will create a movie information application that operates solely on pure Java technology using JavaFX. This course is designed to help you deeply understand the "structure connecting screens and logic" by directly implementing UI event handling, asynchronous logic, and user interaction flows in Java before moving on to web and smartphone apps. You will train your structural thinking by separating business logic and UI through integration with Spring Core, and learn how to solve UI performance degradation issues that may occur when fetching movie information from external APIs using asynchronous processing. Through this, you will clearly understand the principles of data flow, event listeners, and thread-based asynchronous processing, elevating your understanding of the Java language itself to the next level. In short, this course is a "practical stage to experience the essence of UI and the core of asynchronous processing with Java before moving to the web." Do not forget that this is not a class for just typing along with code, but a learning experience where you can personally master the principles of connecting UI and logic.

JAVA is a programming language, just like the C language. JAVA can be used for web development and application development, and here we will learn JAVA before doing web development.

IntelliJ IDEA Conf 2025 is an annual online conference hosted by JetBrains that provides valuable sessions for Java and Kotlin developers. It covers various topics including AI adoption, Spring Boot, Gradle, Kafka, database management, and also shares insights on cloud integration, secure coding, developer performance improvement, and advanced development techniques. This conference is open to both professional and beginner developers, offering opportunities to explore the latest technologies along with productivity tips for writing high-quality code faster.

Through the 25 patterns of OODP, you will learn various ways to design software in an object-oriented manner.