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Completed 6 episodes ~ 1h 24m total read

Algorithm Interview 2026: Data Structures — Know Your Tools

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Episodes

6 items • ~1h 24m
  1. 1

    Arrays & Strings: The Interview Bread and Butter

    Updated

    Arrays and strings appear in 40%+ of interviews and hide surprising complexity. Master prefix sums, sliding windows, two pointers, and in-place tricks that turn O(n²) into O(n).

    Published Mar 10, 2026 • 15 min read
  2. 2

    Hash Maps & Hash Sets: Turn O(n²) Into O(n) Every Time

    Updated

    The hash map improves interview performance more than any other structure. Learn how it works, when O(1) breaks, and the 5 patterns covering 80% of hash-related problems.

    Published Mar 10, 2026 • 15 min read
  3. 3

    Linked Lists: The Data Structure That Trips Everyone Up

    Updated

    Linked lists look simple until live pressure hits. Master reversal, cycle detection, the runner technique, and merging — with the mental model that kills null pointer errors.

    Published Mar 11, 2026 • 13 min read
  4. 4

    Stacks & Queues: Simple to Learn, Sneaky to Master

    Updated

    Stacks feel easy until the interviewer asks for a queue using two stacks. Learn the monotonic stack, deque patterns, and the BFS connection that unlocks hard O(n) solutions.

    Published Mar 11, 2026 • 13 min read
  5. 5

    Trees & Binary Search Trees: The Interview Favorite

    Updated

    Trees are the most-tested structure in FAANG interviews. Master DFS, BFS, all traversals, LCA, path sums, and BST validation with a recursive framework that makes it click.

    Published Mar 12, 2026 • 13 min read
  6. 6

    Graphs: From Zero to BFS/DFS in One Post

    Updated

    Graphs intimidate more than any other topic — but most problems use just 4 techniques. Master BFS, DFS, topological sort, and union-find with a clear decision framework.

    Published Mar 12, 2026 • 15 min read