Arrays and Maths: Subarray problems, Prefix Sum Technique, 2D arrays, Number Theory

Backtracking: Recursion, Permutations & Combinations

Binary Search Trees: Insertion, deletion, traversal

Bit Manipulation: Basic operations, Bit masking, Hamming distance

Hashing: Collision resolution techniques, Hash tables, Applications of hashing

Linked Lists: Types and implementation, Pointer-based questions

Queues: Implementation, Circular queue, Priority queue, Deque

Searching: Linear search, Binary search and variations

Sorting: Bubble sort, Selection sort, Insertion sort, Quick sort, Merge sort

Stacks: Implementation, Expression evaluation, Sequence and pattern identification, Histogram and area problems

Strings: String manipulation, String matching

Trees: Inorder, Preorder, Postorder, Level Order traversal, Lowest Common Ancestor

Two Pointers: Opposite direction pointers, Same direction pointers, Three pointer techniques

Dynamic Programming: Classic DP problems, Array, tree, and graph-based problems

Graphs: BFS, DFS, Shortest Path algorithms, Minimum Spanning Tree algorithm

Greedy Algorithm: Classic problems, Array and graph-based problems

Heaps: Min Heap, Max Heap

Tries: Basic operations, Word search problems

Case Studies: Social Media (Instagram, WhatsApp), E-Commerce (Amazon, Flipkart), Aggregator (Uber, Swiggy, Zomato)

High-Level Design: System architecture, Scalability, Performance optimization, Database and storage design, Security, Reliability, Networking and integration strategies

Low-Level Design: Design patterns, UML diagrams, SOLID principles