Welcome! In this tutorial, you'll learn how to create a hash table from scratch in C. Hash tables are powerful data structures that let you store and retrieve data quickly. By following along, you'll gain hands-on experience and a deeper understanding of how hash tables work.
- Fast: Insert, search, and delete operations are quick.
- Useful: They're used in many computer science problems.
- Educational: Writing one yourself teaches you a lot about data structures and C.
- How hash tables work under the hood
- When to use hash tables—and when not to
- How to handle collisions and resizing
- Practical C programming skills
- Basic knowledge of C syntax
- Familiarity with compiling and running C programs
-
Start with the Introduction:
Learn what hash tables are and why they're important.
👉 Introduction -
Understand the Structure:
See how a hash table is organized in C.
👉 Hash table structure -
Write Hash Functions:
Learn how to convert keys into table indices.
👉 Hash functions -
Handle Collisions:
Discover how to deal with keys that hash to the same index.
👉 Handling collisions -
Implement Table Methods:
Add functions for inserting, searching, and deleting data.
👉 Hash table methods -
Resize the Table:
Make your hash table scalable by resizing it when needed.
👉 Resizing tables -
Explore Alternatives:
Check out other ways to handle collisions.
👉 Appendix: alternative collision handling
- If you get stuck, try searching online or open a GitHub Issue.
- The full implementation is about 200 lines of code and should take 1–2 hours.
Tutorial by James Routley
More at routley.io
Happy coding!