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Foundations and Linear Structures
Big-O analysis (time and space complexity); arrays and strings with two pointers and sliding window patterns; hashmaps and sets for lookup problems; stacks, queues, and monotonic stack patterns.
Module Content
Big-O & Complexity Analysis
The vocabulary interviewers use. Master O(1), O(log N), O(N), O(N log N), O(N²) and how to recognize each from code. FIND_VIDEO: search 'big O notation time complexity explained' — recommended channel: HackerRank / freeCodeCamp. Aim for 10 min or under.
Quiz: Reading Time and Space Complexity
How to look at code and immediately classify it. Plus the space cost of recursion and the common analysis traps.
Arrays & Strings: Two Pointers and Sliding Window
Two of the highest-yielding interview patterns. Recognize them and you'll solve a third of all array/string problems with O(N) algorithms. FIND_VIDEO: search 'two pointers sliding window pattern leetcode' — recommended channel: NeetCode / Tushar Roy. Aim for 12 min or under.
Quiz: Two Pointers and Sliding Window Patterns
When to reach for two pointers, when for sliding window, and the canonical problems each solves.
HashMaps & HashSets
The single most-used data structure in interview problems. Trade space for time; O(1) lookups unlock most solutions. FIND_VIDEO: search 'hashmap hashset interview problems' — recommended channel: NeetCode / Abdul Bari. Aim for 10 min or under.
Quiz: When to Reach for a HashMap
The mental signals that scream 'hashmap'. Plus the patterns that combine hashmaps with other techniques.
Stacks, Queues & Monotonic Stack
LIFO and FIFO patterns. The monotonic stack is the secret weapon for 'next greater element' style problems. FIND_VIDEO: search 'stack queue monotonic stack interview' — recommended channel: NeetCode / Tushar Roy. Aim for 11 min or under.
Quiz: Stack and Queue Patterns
When stack and queue help. The monotonic stack pattern that solves several seemingly different problems.
Linked Lists: Traversal, Reversal & Fast/Slow Pointers
Linked lists from the ground up: traversal, in-place reversal, and the fast/slow-pointer techniques (cycle detection, find-middle) Mock 2 requires.
Quiz: Linked List Patterns
Test your understanding of linked-list traversal, reversal, and fast/slow-pointer patterns.
Mock 1 — Arrays, Strings, Hashmaps (45 min)
Practice three timed array, string, and hashmap interview problems in the downloadable Jupyter notebook. Complete the functions, tests, complexity notes, and interview reflection, then submit the notebook.
Mock 2 — Linked Lists (45 min)
Practice three pointer-focused linked-list interview problems in the downloadable Jupyter notebook. Complete the functions, pointer trace, complexity notes, and reflection, then submit the notebook.