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IOI 2021 Predictions Part 2 & My Thoughts from Day 1 & Expectations about Day 2

Revision en1, by Mr_Tree_HLD_LCA_Master, 2021-06-24 11:20:54

Hello, my fellow coders, as you can see results of Day 1 turned out to be really unexpected to everyone.

Even I was so confused when I finished Day 1, got out of the room ad saw the results. I thought it was some kind of mistake cause I usually don't tend to get a better rank than Grandmasters in Codeforces and Olympiads and the same holds for IOI medalists.

However, on Day 1 this was not the case.

I was really happy to see that I had gotten a better rank than some really talented people in CP, but that didn't hold for long since it was only Day 1 and anything could happen in Day 2 which could lead me to get a really bad place or not getting a medal.

Apart from that, I have to note that I do not consider myself better than the people I mentioned. Now let's get on with Day 1 problems.

First of all, let's talk about the difficulty and then the quality If someone only sees the results he will think that the problems were surprisingly hard and I heard this opinion from many contestants who did good and bad in the contest, a lot of times.

Now I can not, of course, disagree with them but in the first half of the contest, the problems seemed pretty standard to me and easy for someone to score a pretty decent score.

For example when first I saw the problem "Distributing Candies" I thought that "Ok this seems like some Lazy Segment Tree problems or maybe we can do it with Sqrt Decomposition and in general use some advanced data structure". However, it was pretty hard and needed time (or at least for me) to score some good points.

Now for problem "Keys" the first 3 subtasks were pretty standard and easy for the majority of contestants, as they required some observations and some graph searching algorithms such as DFS or BFS.

The rest subtasks were hard for me to process in the little time left but overall in my opinion I still think of it as a nice medium graph problem even though it is hard.

Now for the last problem "Fountain Parks" I saw many contestants get 70 points which surprised me since my ideas in the contest only led me to around 15 to 35 points.

On the other hand, it was the only problem I didn't give much thought or time to it since I was obsessed with getting a good score in the problem "Keys".

Now my point is that "HARD" is not the most accurate word to describe the problems, cause as a matter of content they seem kind of easy, whereas I also support that they are hard as I explained above. Overall they are "WEIRD" and "HARD" but still, it is not that accurate.

Now about the quality, I find them REALLY good and the idea, story, and the problems, of course, themselves seem very interesting.

About that, I would also like to thank the authors of the problems and everyone who got involved in the process both with the problems and the IOI.

Now about Day 2, my opinion is that the problems are gonna be more normal and may be easier since there are a lot of equal scores which need to be distinct otherwise the medal distribution is gonna be hard.

All this is my opinion so you may find it silly or it may seem weird to you.

To close off, Good Luck to all teams on Day 2!!!

Tags #ioi2021, day 1, day 2, thoughts


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en2 English Mr_Tree_HLD_LCA_Master 2021-06-24 11:22:45 211
en1 English Mr_Tree_HLD_LCA_Master 2021-06-24 11:20:54 3333 Initial revision (published)