Hello Codeforces community,
We are excited to invite you to TOKI Indonesian NOI Open Contest 2024 — an online mirror contest for the Indonesian National Olympiad in Informatics 2024. This national olympiad is one of the stages required for our students to qualify to represent Indonesia in the International Olympiad in Informatics (IOI) 2025. You may have seen our past open olympiads (2015, 2016, 2017, 2018, 2019, 2020, 2021, 2022, 2023), and you can check our past problems here.
The contest is similar to IOI: 2 contest days (+ 1 trial session), each consisting of 3 IOI-style (partial, subtasks) problems to be solved in 5 hours. The schedule is as follows:
- Day 0: 27 August 2024 11:00 — 28 August 2023 06:00 UTC (trial session)
- Day 1: 28 August 2024 07:00 — 29 August 2023 06:00 UTC
- Day 2: 29 August 2024 07:00 — 30 August 2023 06:00 UTC
Each contestant can select any 5-hour window (2-hour for Day 0) within the time range to do the contest for each contest day. The 5-hour timer starts by clicking the "start" button within the contest duration, and no additional time is given if a contestant starts the contest less than 5 hours before the contest ends. The scoreboard will be hidden until the contest has ended.
All three contests are now available on TLX. Please register in those contests. You may need to register for a TLX account if you do not have one. For more detailed information and rules, see our official website.
See you on the leaderboard!
UPD: The open contest windows are over!
You can view the scoreboard for the open contest here. Upsolving and the editorials will be available once the final results of the official contest is announced.
if the probelms are as good as the problems were on toki open i will definately go:D
We have just published the problems and reset all contestant start times. Apologize for the inconvenience!
Hiya all! Don't forget to start your Day 1 contest before the time window ends! 😁
Good luck and have fun everyone! 🔥 🔥 🔥 🔥
As Scientific Committee of Indonesian NOI, I encourage you to participate on Open OSN. The problems for day 2 (today) are more interesting than day 1 (yesterday). Good Luck and Have Fun
still did not do day 2 but day 1 was really amazing,problems were so interesting especially A and B
How to solve Day 1 B?
Binary search on the minimum number elements you need to add. Lets say you want to check if you can with $$$X$$$ added, you do a sliding window of size $$$K-X$$$ (also you need to check the windows that loop around the array since you can do rotations) and see if you can add $$$X$$$ numbers in the range to make it consecutive numbers, to do that check if all elelemnts are unique and if $$$max - min + 1 \le K$$$, for min and max queries I used a sparse table
Thanks
Can upsolving be opened?