Data Structures

Lessons

1. 1

   Why Data Structures Matter

   Free

   Understand why the choice of data structure determines performance, and evaluate structures by their operation costs.

   Beginner·25 min
2. 2

   Arrays and Dynamic Arrays

   Explain array memory layout, why random access is O(1), and how dynamic arrays grow with amortized O(1) appends.

   Beginner·35 min
3. 3

   Linked Lists

   Implement singly, doubly, and circular linked lists; know when they beat arrays and when they do not.

   Beginner·40 min
4. 4

   Stacks

   Implement a stack and use it for balanced parentheses and expression evaluation.

   Beginner·40 min
5. 5

   Queues

   Implement queues with a deque, and recognize deques, priority queues, and their uses in BFS and job queues.

   Beginner·35 min
6. 6

   Hash Tables

   Explain hashing, collision handling, load factor, and why operations are O(1) average and O(n) worst case.

   Intermediate·45 min
7. 7

   Trees and Binary Search Trees

   Implement a BST with insert/search/delete and all four traversals; understand why balancing matters.

   Intermediate·50 min
8. 8

   Heaps

   Implement heap insertion and extraction, and use heaps for priority queues, heap sort, and the top-K pattern.

   Intermediate·40 min
9. 9

   Graphs

   Represent graphs and implement BFS and DFS from scratch.

   Intermediate·50 min
10. 10

    Tries

    Implement a basic trie and explain where prefix trees are used (autocomplete, spell check, IP routing).

    Intermediate·35 min
11. 11

    Segment Trees and Fenwick Trees

    Use segment trees and Fenwick (binary indexed) trees for O(log n) range queries and point updates.

    Advanced·50 min
12. 12

    Passion Project: Data Structures Library

    Build and publish a tested data structures library implementing the core structures from scratch.

    Advanced·240 min
13. 13

    Data Structures Job Readiness

    Translate data structures knowledge into resume bullets and confident interview answers.

    Beginner·30 min