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Data Structures & Algorithms

Core CS: arrays, lists, stacks, queues, hash tables, trees, graphs, sorting, searching, recursion and Big-O.

26 lessons about 9 hours Hard
Learn it by writing it.

Every lesson runs real code in your browser, checked the moment you submit. No installing anything, no setup, no waiting.

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What this course covers

  1. Measuring Speed: Big-O
  2. Arrays & Lists
  3. Linked Lists
  4. Stacks (LIFO)
  5. Queues (FIFO)
  6. Hash Tables (Dictionaries)
  7. Tries (Prefix Trees)
  8. Recursion
  9. Binary Search
  10. Bubble and Selection Sort
  11. Merge Sort
  12. Advanced Sorting: Quicksort & Counting Sort
  13. String Algorithms
  14. Two Pointers & Sliding Window
  15. Trees and Binary Search Trees
  16. Tree Traversals
  17. Binary Search Trees
  18. Heaps & Priority Queues
  19. Graphs: Representation
  20. Graph Traversal: BFS & DFS
  21. Shortest Paths
  22. Backtracking
  23. Dynamic Programming
  24. Greedy Algorithms
  25. Bit Manipulation
  26. Union-Find (Disjoint Set)

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