Data Structures & Algorithms (DSA)

Master Complexity Analysis, Arrays, Strings, Hashing, Linked Lists, Stacks, Queues, Recursion, Searching, Sorting, Trees, BSTs, Heaps, Tries, Graphs, DSU, Greedy, Dynamic Programming, Bit Manipulation, Segment Trees & Math

• Time & Space Complexity Fundamentals
• Big O, Big Ω, Big Θ Notations
• Amortized Analysis & Recurrence Relations

• Array Operations & Memory Layout
• Prefix Sum, Suffix Sum & Difference Array
• Kadane's Algorithm & Dutch National Flag
• Array Rotations & Merging Sorted Arrays
• Binary Search on Answer / Solution Space

• StringBuilder & StringBuffer Operations
• Character Frequency & String Compression
• KMP Pattern Matching, Rabin-Karp & Z Algorithm

• HashMap, HashSet & Custom Hashing
• Collision Handling (Chaining & Open Addressing)
• Prefix Hash & Frequency Counting

• Singly & Doubly Linked List Operations
• Middle Node, Remove Nth from End & Cycle Detection
• Merge Sort on LL, Flatten LL & LRU Cache

• Stack LIFO Operations & Balanced Parentheses
• Next Greater Element & Stock Span Problem
• Largest Rectangle in Histogram & Stack using Queues

• Queue FIFO, Circular Queue & Deque
• Queue using Stacks
• Priority Queue & Heap Interface

• Recursion Base Cases & Tower of Hanoi
• Backtracking: Sudoku Solver & Rat in a Maze
• Combination Sum, Word Search & Generate Parentheses

• Linear Search & Binary Search (Iterative & Recursive)
• Exponential Search & Jump Search
• Interpolation Search & Ternary Search

• Elementary Sorts (Bubble, Selection, Insertion)
• Divide & Conquer (Merge Sort & Quick Sort)
• Counting, Radix, Bucket, Heap & Shell Sort

• Binary Tree Traversals (Recursive, Iterative, Morris)
• Tree Diameter, Balanced Check & LCA
• Views (Left, Right, Top, Bottom) & Zigzag
• Serialize/Deserialize & Tree Construction

• BST Insert, Search, Delete (0/1/2 Children) & Validation
• Inorder Successor/Predecessor & Kth Smallest/Largest

• Build Heap O(N) & Heapify Up/Down
• Kth Element & Merge K Sorted Arrays/Lists
• Find Median in Data Stream (Two Heaps)

• Trie Insert, Search, StartsWith & Delete
• Auto-Complete & Longest Common Prefix

• Graph Representation, BFS, DFS & Connected Components
• Shortest Path (Dijkstra, Bellman-Ford, Floyd-Warshall, A*)
• Minimum Spanning Tree (Prim's & Kruskal's)
• Topological Sort, Bipartite, Bridges, Articulation & SCC

• Union-Find by Rank/Size with Path Compression & Cycle Detection

• Activity Selection & Fractional Knapsack
• Job Scheduling, Huffman Coding, Gas Station & Jump Game

• 1D DP (Fibonacci, Climbing Stairs, House Robber, Decode Ways)
• 2D DP (0/1 Knapsack, Unique Paths, Edit Distance, MCM)
• DP on Trees, Bitmask DP & Digit DP

• Bitwise AND, OR, XOR & Left/Right Shift
• Count Set Bits, Power of Two & Single Number
• Bitmasking & Generating Subsets using Bits

• Segment Tree (Build, Point Update, Range Query)
• Fenwick Tree / BIT & Sparse Table

• AVL Trees & Red-Black Trees (Theory)
• B-Tree, B+ Tree & Skip List (Theory)

• GCD/LCM (Euclidean Algorithm) & Sieve of Eratosthenes
• Fast Exponentiation, Prime Factorization & Modular Arithmetic