Master arrays, hash maps, linked lists, stacks, queues, trees and graphs with hands-on Python exercises. Build the foundation for coding interviews.
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Learn the fundamentals of sequential data storage, master Python lists and strings, and discover the sliding window and two-pointer patterns that appear in dozens of interview problems.
Master O(1) lookup with Python dictionaries and sets. Learn the counting pattern, the complement pattern, and how sets eliminate duplicates instantly.
Understand how linked lists work, why they exist alongside arrays, and master the fast/slow pointer technique that solves cycle detection, middle-finding, and more.
Master LIFO and FIFO data structures, learn the monotonic stack pattern for next-greater-element problems, and use queues for BFS — the foundation of graph traversal.
Understand binary trees, master DFS and BFS traversals, and learn how graphs generalize trees. These structures power databases, file systems, social networks, and navigation systems.
Combine everything you've learned across arrays, hash maps, linked lists, stacks, queues, trees, and graphs. Solve multi-pattern problems and build a mini-project that ties it all together.