Java 20-Day Challenge 🚀

Welcome to my Java 20-Day Challenge! For the next 20 days, I will be dedicating time each day to improve my Java programming skills and dive deeper into different data structures and algorithms. This repository contains all the code and notes I created during this challenge.

Table of Contents

• Overview

• Daily Progress

  • Day 1: Array & ArrayList
  • Day 2: Linked List
  • Day 3: Linked List Palindrome
  • Day 4: Stack
  • Day 5: Queue Basics
  • Day 6: Queue Implementation
  • Day 7: Trees and Tree Traversals
  • Day 8: Binary Tree (BT)
  • Day 9: Practise on BT
  • Day 10: Binary Search Tree
  • Day 11: BST Delete Property
  • Day 12: Hashing
  • Day 13: HashMap

• Resources

• Contact

Overview

I am taking on this 20-day challenge to enhance my understanding of fundamental data structures and algorithms using Java. Each day, I will focus on a specific topic and implement related code to reinforce my learning. This README will be updated daily to reflect my progress.

Daily Progress

Day 1 - Array & ArrayList

• Topics Covered:
  • Basics of Arrays
  • Introduction to ArrayLists
  • Differences between Arrays and ArrayLists
• Code:
  • Array
• Summary:
  • Explored the fundamental differences between arrays and arraylists in Java.
  • Practiced basic operations like adding, removing, and accessing elements.

Day 2 & 3 - Linked List

• Topics Covered:
  • Singly Linked List
  • Basic Operations (add, remove, traverse)
  • Linked List Palindrome - Important for placement
• Code:
  • Linked List Implementation
• Summary:
  • Implemented a basic singly linked list from scratch, understanding how nodes are linked together and practicing operations such as insertion and deletion.
  • Implemented a solution that involves reversing the second half of the list and comparing it with the first half.

Day 4 - Stack

• Topics Covered:
  • Stack Data Structure
  • Implementation using ArrayList and Linked List
• Code:
  • Stack Implementation
• Summary:
  • Learned about the Stack data structure and its operations. Implemented Stack using both ArrayList and Linked List.

Day 5 - Queue Basics

• Topics Covered:
  • Queue Data Structure with (Queue and Linked List) library.
  • Comparison with Stack and Queue.
• Code:
  • Queue Implementation
• Summary:
  • Learned about the Queue data structure and its operations.

Day 6 - Queue Implementation

• Topics Covered:
  • Queue Implementation using Array and Linked List
• Code:
  • Queue Implementation

Day 7 - Trees and Tree Traversals

• Topics Covered:
  • Tree Data Structure
  • Tree Traversal Methods: Preorder, Inorder, Postorder, Level Order
• Code:
  • Tree Implementation
• Summary:
  • Learned about tree data structure and different traversal methods.
  • Implemented tree traversal methods: Preorder, Inorder, Postorder, and Level Order.

Day 8 - Binary Tree (BT)

• Topics Covered:
  • BT Properties (Number of nodes, Number of leaf Nodes, Height)
• Code:
  • BT Implementation

Day 9 - Practise on BT

• Code:
  • Practise

Day 10 - Binary Search Tree

• Topics Covered:
  • BST Properties (Insert, Search, InOrder Traversal)
• Code:
  • Binary Search Tree

Day 11 - BST Delete Property

• Topics Covered:
  • BST Properties (Delete Cases)
• Code:
  • BST Delete Property

Day 12 - Hashing

• Topics Covered:
  • HashSet
  • HashMap
• Code:
  • Hashing

Day 13 - HashMap Implementation

• Topics Covered:
  • HashMap
• Code:
  • HashMap-Implementation

Resources

• Official Java Documentation

Contact

Feel free to reach out if you have any questions or suggestions!

• Email: robiussanijabiullah@gmail.com
• LinkedIn: Rabbius Sani Jabiullah

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Thanks for visiting my repository! Stay tuned for more updates. 😊