Competitive Programming in Haskell

on YouTube ↗01h 10m

" summary

Shows Haskell solving contest problems live: a working pipeline from input string to output using interact and lazy IO to treat the whole run as a pure function, a simple exponent-and-sum solution that passes samples, a shopping‑list intersection sped from TLE to accepted by switching to ByteString and Set optimisations, and a lazy recursive graph DP that leverages memoisation to count good endings. A 30‑minute contest runs with multiple accepted solutions and one team solves all problems.

AI-written summary · about

" chapters (24)

1. 0:00Introduction by the host and talk overview
2. 0:46What is competitive programming – core structure and constraints
3. 1:47Strange incentives – correctness over maintainability
4. 2:51Popular sites and Haskell resources
5. 3:22Contest announcement and setup
6. 4:30Problem 1 – Exponent parsing and summing
7. 5:52Using interact and Haskell’s functional approach
8. 6:52Writing a minimal solution for problem 1
9. 9:13Testing and submitting the first solution
10. 10:30Problem 2 – Common items in shopping lists
11. 12:08Using Set and Haskell containers
12. 14:16Performance tuning with ByteString
13. 17:14Re-submitting after optimisation
14. 18:06Problem 3 – Graph traversal and lazy evaluation
15. 21:52Contest rules explained
16. 22:50Contest starts
17. 54:48Contest winners and wrap-up
18. 55:17Q&A – Can Haskell win CFP contests
19. 57:12Useful parsing libraries and code snippets
20. 1:03:01Where Haskell struggles in contests
21. 1:05:03Educational use of competitive programming
22. 1:07:20Why not Parsec – tooling decisions
23. 1:07:53Recreational problem-solving without pressure
24. 1:08:29Final thanks and speaker applause

" related talks

• 01h 22mHaskell for Everyday ProgrammersVenkat Subramaniam · Functional Conf 2014
• 59mWeb Programming and Streaming Data in Haskell - Part 1 of 2Michael Snoyman · LambdaConf 2017
• 46mPainless software development with HaskellPawel Szulc · Lambda World Cádiz 2019
• 01h 02mHaskell for Java ProgrammersVenkat Subramaniam · Great Indian Developer Summit 2015
• 01h 04mHaskell - A Peek Inside the Ivory TowerDaniel Chambers · NDC Sydney 2018
• 39mCoder Decoder: Functional Programmer Lingo Explained, with PicturesKatie Miller · Strange Loop 2014
• 54mHaskell Project Showcase and Community ContributionsJasper Van der Jeugt · ZuriHac 2026
• 03h 04mHaskell for Beginners: Learn Functional Programming from ScratchMichael Sperber · ZuriHac 2026