Data Structures and Algorithms (DSA) & Java Foundations

This repository contains resources, and important questions for core DSA concepts and fundamental Java programming each topics.

Completed Topics

Basics of Programming

• Flowcharts & Pseudocodes
• Variables & Data Types
• Conditional Statements
• Operators

Loops & Functions

• For loop, While loop, Do-while loop
• Patterns
• Functions

Arrays

• Introduction to Arrays
• Searching & Sorting
  • Linear search
  • Binary search
  • Selection sort
  • Bubble sort
  • Insertion sort
  • Count sort

2D Arrays & Strings

• 2D Arrays
• Strings

Bit Manipulation

• Binary number system
• Bitwise operators
• Bit operations
• Fast exponentiation

Object-oriented programming

• Objects & Classes
• Constructors and related concepts
• Abstraction, Encapsulation
• Inheritance, Polymorphism
• Abstract classes
• Interfaces

Recursion

• Basics of Recursion
• Recursive problems
  • Factorial
  • Fibonacci
  • Power of a number
  • Tower of Hanoi

Divide and Conquer

• Introduction to Divide and Conquer
• Merge Sort
• Quick Sort

Time and Space Complexity

• Big O Notation
• Analyzing algorithms
• Common complexities
• Space complexity

Linear Data Structures

• Backtracking
  • N-Queens Problem
  • Sudoku Solver
• ArrayLists
• Linked lists
  • Insertion and deletion operations
  • Midpoint of linked list
  • Merging sorted linked lists
  • Reversing a linked list
• Stacks and Queues
  • Stack using arrays and linked list
  • Queue using arrays
  • Dynamic queue class
  • Circular queue

Advanced Data Structures

• Binary Trees & BST
  • Introduction to Binary Trees
  • Tree traversals
  • Height and LCA of tree
  • Binary Search Trees
  • Insertion and deletion in BST
  • Types of balanced BSTs
• Heaps/Priority Queues
  • Min/Max heaps
  • Heap Sort
  • Priority Queues implementation
  • Insert and Delete operations
• Hashing (Maps & Sets)
  • Hashmaps
  • Hashsets
  • Implementation details
• Tries
  • Basic operations and implementation
• Graphs
  • Introduction and terminology
  • Graph traversals (DFS and BFS)
  • Weighted and directed graphs
  • Minimum Spanning Trees
  • Cycle Detection
  • Dijkstra's algorithm
  • Bellman Ford Algorithm
• Segment Trees
  • Creation and range queries

Dynamic Programming

• Fundamentals of DP
• Memoization
• Knapsack, Factorial, Fibonacci using DP
• Longest Common Subsequence
• Edit distance
• Matrix Chain Multiplication

Learning Resources

• Books
• Online courses
• Practice websites like LeetCode and Codeforces
• Community forums

Contributing

Feel free to contribute to this repository by adding implementations, improving existing code, or suggesting additional topics.