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// Phase 4 · Computer science core · course 10

Data Structures & Algorithms

The patterns behind most junior coding interviews: Big-O, hash maps, two pointers and stacks.

Intermediate13 lessons ready4 coming soon

You'll be able to

  • Analyze time and space complexity with Big-O
  • Recognize the right pattern: hash map, two pointers, sliding window, binary search, BFS/DFS, heap or DP
  • Implement linked lists, trees and graph searches from scratch
  • Run a 45-minute coding interview with a clear, confident script

Syllabus

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  1. 1Big-O in Plain EnglishHow to describe the speed of your code, and why interviewers always ask.Free12 min
  2. 2Hash Maps & SetsThe single most useful pattern for turning slow solutions into fast ones.🔒14 min
  3. 3Two Pointers & StacksTwo more patterns that unlock a large share of easy and medium interview questions.🔒15 min
  4. 4The Sliding Window PatternSolve "best stretch of the array" problems in one pass instead of two loops.🔒12 min
  5. 5Binary SearchFind anything in a sorted list of a billion items in about 30 steps.🔒12 min
  6. 6Sorting Algorithms, VisualizedWatch bubble, selection and insertion sort run, then learn why real code uses O(n log n).🔒14 min
  7. 7Recursion, Step by StepFunctions that call themselves. Watch the call stack grow and shrink.🔒14 min
  8. 8Linked ListsNodes that point to the next node. A favorite for learning pointers and an interview classic.🔒12 min
  9. 9Trees & Binary Search TreesHierarchies of nodes, depth-first traversal, and searching in O(log n).🔒15 min
  10. 10Graphs: BFS & DFSModel networks of connections and find paths through them.🔒15 min
  11. 11Heaps & Priority QueuesAlways grab the smallest (or biggest) item fast. Perfect for "top K" problems.🔒10 min
  12. 12Dynamic Programming, DemystifiedStop recomputing the same answers. Memoization and tables, explained gently.🔒15 min
  13. 13The 45-Minute Interview, Start to FinishA repeatable script for any coding interview, practiced on a real question.🔒15 min
  14. 14Greedy algorithmsComing soon
  15. 15Backtracking: trying every optionComing soon
  16. 16Tries & string algorithmsComing soon
  17. 17Union-find & advanced graphsComing soon