An Insight from My Competitive Programming Journey

A bit of insight from somebody that never won competitive programming contest even once on the national level.

Transcript

1. An Insight from My Competitive Programming Journey epicurean @ Sep 11th, 2020
2. My Little Background First time doing competitive programming: Third year of senior high school. To be clear, I’m not a hardcore competitive programmer. I do competitive programming as a hobby. Never “win” even once. My highest rank as a team is 4th place in a provincial or maybe national level? I’m not really sure. I’m known as “epicurean” on the competitive programming platform. As a team, we usually going as “AnakRantauMenderita”.
3. Why doing competitive programming in the first place?
4. Why Am I Doing This? I love programming in general. I also love challenge. The easiest way to acquire those two are by doing competitive programming. We got both programming and challenge at the same time.
5. Remember that competitive programming is a problem solving competition, not a development related stuff.
6. So, should not bring your development habit onto competitive programming contest and vice versa.
7. How do I learn competitive programming?
8. Topics on Competitive Programming If you already participated in a competitive programming competition then you must be aware that there are a lot topics you need to know. Computational geometry, dynamic programming, greedy, number theory, game theory, sorting, graph theory, tree, and so on. Remember that the first step to solve a problem is to identify the problem first!
9. The question is how do we identify the problem? Spoiler: Identify the topic first.
10. Searching Sorting Greedy Dynamic Programming Number theory Computational Geometry
11. Searching Sorting Greedy Dynamic Programming Number theory Computational Geometry
12. Searching Sorting Greedy Dynamic Programming Number theory Computational Geometry Horizontal Learning
13. Searching Greedy Number theory Computational Geometry Vertical Learning Sorting Dynamic Programming
14. Learn the basic of as many topics as you can. Then, get to know more by learning & practicing on the several topics.
15. Algorithm Design & Analysis Identify what kind of algorithm you can apply in regard of the input size.
16. Algorithm Design & Analysis Identify what kind of algorithm you can apply in regard of the input size. This bad boy will be your best friend
17. Friendship ended with brute-force approach. Now big-O analysis is my best friend.
18. What is Big-O Anyway? To put it simply, big-O analysis usage is to identify the worst case of an algorithm. It count the number of computations needed to finish the algorithm. It shows us the upper bound of an algorithm. My rule of thumb: 100,000,000 computations are done in one second. You don’t need to dive too deep on this one although it would be great.
19. Big-O Time Table Source: The Algorithm Design Manual His rule thumb is that 1 billion computations is done in one second.
20. Big-O Time Table Source: Competitive Programmer Handbook
21. What’s left is to practice more and participate in an online competition. Do it solo first.
22. Then, find yourself a teammate to participate in a team based competitive programming competition.
23. How many competitions are out there?
24. There are actually a lot of online competitions on and many more...
25. As for the National competition, here in Indonesia we have and many more...
26. Each competition usually have their own characteristics. By that I mean a certain competition would bring a certain topics. Try to analyze the problems from years before and you will understand what I meant to say.
27. Also, don’t exhaust yourself before the competition. Take some rest the day before and you’re good to go.
28. What’s the benefit for me by doing this?
29. (Almost) Easy Online Coding Challenge & Technical Interview I got myself a high paying part-time job at I eventually secured myself an internship at
30. Although I’m saying this, please focus on your study. Don’t do part-time if you don’t need to. You are most welcome to do internship though.
31. Also, you got a better chance to work at the giant tech company such as Google, Facebook, Twitter, etc. Their first step on recruiting someone is to review the applicant’s resume. You got an upper hand if you do a lot of coding competitions. Moreover if you have won at least once. Winning in the ICPC is a great choice. The second step is online coding challenge. You are more likely able to do this well if you have a solid skill in competitive programming.
32. A similar coding problem from Bukalapak technical interview back then hackerrank.com/challenges/matrix-rotation-algo/problem
33. Alright, now, what’s next?
34. Practice more, duh. You need consistency.
35. Actually, reading about someone successful story in competitive programming is fun. Like, a story about Gennady “tourist” Korotkevich. A programming prodigy. It may motivate you.
36. That’s it. Any questions?