1. Course Introduction

• How to get started with Leetcode?
• How to improve problem-solving skills?
• How To Code Fast in an interview!
• How to ace your DSA Interview?

2. Time & Space Complexity Analysis FREE CHAPTER

• Introduction to Time & Space Complexity
• What is Big O Notation?
• Calculating Time Complexity Example 1
• Checking If Big O Notation Is Acceptable in Interviews
• Calculating Time Complexity Example 2
• Myth About Time Complexity
• Calculating Time Complexity of Recursive Cases
• Recursive Time Complexity Example 2
• Time Complexity Live Demonstration
• Introduction To Space Complexity
• Calculating Space Complexity
• Recursive Space Complexity Example 1
• Recursive Space Complexity Example 2

3. Arrays Theory + Array Practice Problems from Leetcode

• What are arrays and why are they so fast!
• Drawbacks of using Arrays
• How do resizable arrays work?
• Important Array Methods In Java Part 1
• Important Array Methods In Java Part 2
• Important Array Methods In Java Part 3
• Practice Problem 1 - Maximum Sum Subarray
• Practice Problem 2 - Best Time To Buy And Sell A Stock
• Practice Problem 3 - Maximum Product Subarray
• Practice Problem 4 - Product Of Array Except Self
• Practice Problem 5 - Rotate Array
• Practice Problem 6 - Max Consecutive Ones
• Practice Problem 7 - Valid Sudoku
• Practice Problem 8 - K Closest Points To Origin
• Practice Problem 9 - Encode and Decode Strings

4. Sorting Theory + Sorting Practice Problems

• Why is sorting important?
• Introduction To Sorting
• Bubble Sort Theory
• Bubble Sort Implementation
• Selection Sort Theory
• Selection Sort Implementation
• Insertion Sort Theory
• Merge Sort Part 1 - How to merge two sorted arrays
• Merge Sort Part 2 - Merging Two Sorted Arrays Implementation
• Merge Sort Part 3 - Theory
• Merge Sort Implementation
• Quick Sort Part 1 - Partitioning Algorithm
• Quick Sort Part 2 - Understanding how quick sort works
• Counting Sort Part 1 - Theory
• Counting Sort - Implementation
• How is counting sort made stable?
• Radix Sort - Theory
• Radix Sort - Implementation
• Leetcode #283 - Move Zeroes - Java
• Leetcode #75 - Sort Colors - Java
• Leetcode #169 - Majority Element - Java

5. Linked Lists

• Drawback Of Arrays
• What Is Linked List
• Implementing Linked Lists
• Iterating Over Linked Lists
• Inserting In Linked List
• Deleting From Front In Linked List
• What Is Doubly Linked List
• Linked List Class In Java
• Creating Linked Lists
• Using Iterators To Iterate
• Contains
• Iterating In Reverse Order
• Add Methods In Linked List
• Removal Methods In Linked Lists
• Practice Problem 1 - Intersection Of Two Linked Lists
• Practice Problem 2 - Merge Two Sorted Lists
• Practice Problem 3 - Linked List Cycle
• Practice Problem 4 - Reverse Linked List
• Practice Problem 5 - Palindrome Linked List
• Practice Problem 6 - Linked List Cycle II
• Practice Problem 7 - Find Middle Of The Linked List
• Practice Problem 8 - Remove Nth Node From End Of List
• Practice Problem 9 - Add Two Numbers
• Practice Problem 10 - Reorder List

6. Hash Table Theory + Leetcode Practice Problems

• What Is Hash Table
• How does a hash table work?
• Hash Table Collision Resolution
• Types Of Hash Table
• Hash Table Usage
• Practice Problem 1 - Contains Duplicate
• Practice Problem 2 - Two Sum
• Practice Problem 3 - Valid Anagram
• Practice Problem 4 - Group Anagrams
• Practice Problem 5 - Longest Consecutive Sequence
• Practice Problem 6 - Three Sum
• Practice Problem 7 - First Missing Positive

7. Stacks

• Introduction to Stacks
• Using Stacks In Java
• Practice Problem 1 - Valid Parenthesis
• Practice Problem 2 - Min Stack
• Practice Problem 3 - Next Greater Element II
• Practice Problem 4 - Evaluate Reverse Polish Notation

8. Queue

• Introduction to Queue
• How Is Queue Implemented
• Using Queue In Java

9. Array Pattern #1 - Sliding Window Method + Practice Problems

• What is Sliding Window Method? - Part 1
• What is Sliding Window Method? - Part 2
• How to Implement Sliding Window Method Problems Quickly?
• Practice Problem 1 - Longest Substring Without Repeating Characters
• Practice Problem 2 - Longest Repeating Character Replacement
• Practice Problem 3 - Sliding Window Maximum - Java

10. Array Pattern #2 - Two Pointer Method + Practice Problems

• Practice Problem 1 - Container With Most Water - Java
• Practice Problem 2 - Trapping Rain Water - Java
• Practice Problem 3 - Two Sum II - Input Array Is Sorted - Java
• Practice Problem 4 - Valid Palindrome - Java

11. Array Pattern #3 - Math & Geometry

• Practice Problem 1 - Set Matrix Zero
• Practice Problem 2 - Rotate Image
• Practice Problem 3 - Spiral Matrix
• Practice Problem 4 - Pow (X, N)

12. Array Pattern #4 - Intervals

• Practice Problem 1 - Insert Interval
• Practice Problem 2 - Search Insert Position
• Practice Problem 3 - Merge Intervals
• Practice Problem 4 - Meeting Rooms
• Practice Problem 5 - Non Overlapping Intervals

13. Binary Search Theory

• Introduction To Binary Search
• Binary Search Implementation
• Binary Search Complexity

14. Binary Search Pattern #1 - Binary Search Over Rotated Sorted Arrays

• Practice Problem 1 - Find First And Last Position Of Element In Sorted Array
• Practice Problem 2 - Find Minimum In A Rotated Sorted Array
• Practice Problem 3 - Search In A Rotated Sorted Array

15. Binary Search Pattern #2 - Binary Search Over Range

• Practice Problem 1 - Koko Eating Bananas
• Practice Problem 2 - Magnetic Force Between Two Balls

16. Recursion and Backtracking + Leetcode Practice Problems

• What is backtracking and how it is implemented?
• Backtracking Example 1 With Detailed Implementation
• Leetcode #78 - Subsets - Java
• Leetcode #46 - Permutations - Java
• Leetcode #17 - Letter Combinations Of A Phone Number
• Leetcode #39 - Combination Sum - Java
• Leetcode #40 - Combination Sum II
• Leetcode #90 - Subsets II - Java
• Leetcode #51 - N Queens - Java
• Leetcode #79 - Word Search
• Leetcode #212 - Word Search II

17. Binary Trees Theory & Implementation

• Introduction to Binary Trees
• Terms Related To Trees
• Tree Traversal Algorithms
• Level Order Traversal
• Implementing Trees Using References
• Implementing Trees Using Arrays

18. Binary Trees Practice Problems

• Leetcode #100 - Same Tree - Java
• Leetcode #572 - Subtree Of Another Tree - Java
• Leetcode #101 - Symmetric Tree - Java
• Leetcode #104 - Maximum Depth Of A Binary Tree - Java
• PreOrder Traversal Implementation in Trees Using Arrays
• Leetcode #226 - Invert Binary Tree - Java
• Leetcode #543 - Diameter Of A Binary Tree - Java
• Leetcode #94 - Binary Tree InOrder Traversal - Java
• Leetcode #102 - Binary Tree Level Order Traversal - Java
• Leetcode #112 - Path Sum - Java
• Leetcode #113 - Path Sum II - Java
• Leetcode #993 - Cousins in Binary Tree - Java
• Leetcode #1161 - Maximum Level Sum of Binary Tree - Java
• Leetcode #105 - Construct Binary Tree From Preorder and Inorder Traversal - Java
• Leetcode #110 - Balanced Binary Tree - Java
• Leetcode #199 - Binary Tree Right Side View - Java
• Leetcode #1448 - Count Good Nodes In Binary Tree - Java
• Leetcode #404 - Sum Of Left Leaves - Java
• Leetcode #124 - Binary Tree Maximum Path Sum - Java
• Leetcode #208 - Implement Trie (Prefix Sum Tree) - Java
• Leetcode #211 - Design Add and Search Word Data Structure - Java
• Leetcode #297 - Serialize and Deserialize Binary Tree - Java

19. Binary Search Tree Theory + Leetcode Practice Problems

• Introduction To Binary Search Trees
• Height Balanced BST
• Inserting A New Node in Binary Search Tree
• Inorder Successor And Predecessor
• Deleting A Node In Binary Search Tree
• Leetcode #230 - Kth Smallest Element In BST - Java
• Leetcode #98 - Validate Binary Search Tree - Java
• Leetcode #235 - Lowest Common Ancestor Of A Binary Search Tree - Java

20. Heaps

• Introduction To Heaps
• Implementation Of Heaps
• Insertion in Heaps
• Heap Insertion Implementation
• Deletion in Heaps
• Heapify
• Practice Problem 1 - Kth Largest Element In An Array
• Practice Problem 2 - Find Median from Data Stream
• Practice Problem 3 - Kth Largest Element In A Stream
• Leetcode #1046 - Last Stone Weight - Java
• Leetcode #23 - Merge K Sorted Lists
• Leetcode #253 - Meeting Rooms II
• Leetcode #347 - Top K Frequent Elements

21. Dynamic Programming Theory + DP Practice Problems (1D + 2D + String DP)

• Introduction to Dynamic Programming
• Practice Problem 1 - Climbing Stairs - Java
• Practice Problem 2 - Jump Game - Java
• Practice Problem 3 - Coin Change
• Practice Problem 4 - Target Sum
• Practice Problem 5 - Longest Common Subsequence
• Practice Problem 6 - House Robber
• Practice Problem 7 - Longest Increasing Subsequence
• Practice Problem 8 - Partition Equal Subset Sum
• Practice Problem 10 - Integer Replacement
• Practice Problem 11 - Decode Ways
• Practice Problem 12 - House Robber II
• Practice Problem 13 - Min Cost Climbing Stairs
• Practice Problem 14 - Longest Palindromic Substring
• Practice Problem 15 - Word Break
• Practice Problem 16 - Unique Paths
• Practice Problem 17 - Palindromic Substrings

22. Bit Manipulation Techniques + Leetcode Practice Problems

• Introduction to Bitwise Operators
• Common Bitwise Operators
• Leetcode #136 - Single Number - Java
• Leetcode #338 - Counting Bits - Java
• Leetcode #287 - Find the Duplicate Number - Java
• Leetcode #29 - Divide Two Integers - Java
• Leetcode #268 - Missing Number - Java
• Leetcode #191 - Number of 1 Bits - Java
• Leetcode #371 - Sum Of Two Integers - Java
• Leetcode #7 - Reverse Integer - Java

23. Disjoint Set Data Structure - Union Find Algorithms

• Introduction to Disjoint Set Data Structure
• Understanding Disjoint Set Data Structure
• Implementing Disjoint Set Data Structure Part 1
• Union By Rank Optimization
• Union By Rank Implementation
• Path Compression Optimization
• Path Compression Optimization Implementation

24. Graphs Theory + Graph Practice Problems (BFS/DFS/Shortest Path Algorithm/MST)

• What Are Graphs
• Directed vs Undirected Graphs
• Weighted vs Unweighted Graphs
• Terms Of Graphs Part 1
• Types Of Graphs Part 1
• Types Of Graphs Part 2
• Implementing Graphs Part 1
• Implementing Graphs Part 2
• Graph Implementation Part 3
• Graph Adjacency Matrix Demonstration
• Graph Adjacency List Demonstration
• Introduction To Traversals
• BFS Working
• BFS Implementation
• Rotting Oranges Property Solution
• BFS Property 1
• BFS Over Binary Weighted Graphs
• Introduction to DFS
• DFS Iterative Implementation
• DFS Recursive Implementation
• DFS Important Properties
• Cycle Detection Part 1
• Cycle Detection Part 2
• Cycle Detection Part 3
• Cycle Detection Implementation
• What Is Topological Sorting
• Topological Sorting Example 1
• Single Source Shortest Path Algorithm
• Dijkstra's Algorithm
• Dijkstra's Algorithm Implementation
• Introduction To Bellman-Ford Algorithm
• Bellman-Ford Algorithm Working
• Bellman-Ford Algorithm Implementation
• Introduction To Minimum Spanning Tree
• Prim's Algorithm
• Prim's Algorithm Implementation
• Practice Problem 1 - Course Schedule
• Practice Problem 2 - Number of Islands
• Practice Problem 3 - Find the Town Judge
• Practice Problem 4 - Surrounded Regions
• Practice Problem 5 - Number of Enclaves
• Practice Problem 6 - Flood Fill
• Practice Problem 8 - Rotting Oranges
• Practice Problem 9 - Graph Valid Tree
• Practice Problem 10 - Number Of Connected Components In An Undirected Graph
• Practice Problem 11 - Pacific Atlantic Water
• Practice Problem 12 - Alien Dictionary
• Practice Problem 13 - Clone Graph

25. Greedy Algorithms

• Introduction To Greedy Algorithms
• Practice Problem 1 - Minimum Add To Make Parentheses Valid
• Practice Problem 2 - Best Time To Buy And Sell Stock II
• Practice Problem 3 - Candy

26. Game Theory

• Practice Problem 1 - Nim's Game

27. Advanced String Matching Algorithms

• Introduction To Pattern Matching
• Pattern Matching Brute Force
• Introduction to KMP Algorithm
• KMP Algorithm Version 1 - Extra Space
• Longest Prefix Suffix Brute Force Approach
• Longest Prefix Suffix Brute Force Implementation
• Longest Prefix Suffix Optimized Approach
• Longest Prefix Suffix Optimized Approach Implementation
• KMP Algorithm - Final Optimized Approach
• KMP Algorithm - Final Optimized Approach Implementation

28. String Problems

• Practice Problem 1 - Longest Palindromic String

29. Advanced Data Structure - Segment Trees

• Introduction to Range Sum Query Problem
• Introduction To Segment Tree - Building A Segment Tree
• Answering Queries Using Segment Trees
• Segment Tree Updating Values
• Segment Tree Build Function Implementation
• Segment Tree Query Function Implementation
• Segment Tree Update Function Implementation