CROATIAN OPEN COMPETITION IN INFORMATICS
 
First round comments and statistics
 
Hello everyone,

this year we decided to give you back a bit more feedback on each round than we did before. Each round will be followed by a short editorial where we will try to present fun statistics, comment on events that have happened during the competition and applaud those that performed exceptionally. Although we will sometimes present solutions or fun ways to solve problems, we will not be posting full solutions here. They will be posted separately as they were previous years. If you have any fun stat that you would like to see posted here, or have any other idea for editorials or the competition itself feel free to contact us. You can send us an email on coci@hsin.hr.

Let's start by saying thank you to all 412 people that opened the competition. 271 of you submitted something, which is quite an increase compared to last year. Of the 412 people that opened the problems most were from Croatia (51), followed closely by Thailand (47). Third most present country was Vietnam with 32 competitors.

The winner of this round, with 443 points is Felipe Souza. CONGRATULATIONS!

As languages go there were 101 pure C submissions, 1548 C++ submissions and 301 Pascal submissions. Our new experimental Java had only 32 submissions.

We tried to make this round a bit easy since it is the first one this season and we would like to appeal to a wider audience. We are quite pleased with the results.
Here is a task by task statistics rundown:

TASK NOTE

Completely solved by 253 competitors NOTE was one of the two simplest problems in this round. Some people choose not to submit it at all, strange strange people :). All in all this is the type of problem we feel even people that participate for the first time in competitions can solve. We plan to have one or two tasks of this difficulty each round.
The fastest correct submit for it was only 1:26 after the competition started.

TASK DOMINO

Completely solved by 252 competitors DOMINO was the second simplest problem. It was a bit more difficult than NOTE but results show it was still manageable for most competitors, if not all.
The fastest correct submit for it was only 2:00 after the competition started.

TASK DOBRA

Completely solved by 105 competitors DOBRA was quite more difficult than NOTE and DOMINO. This task was a bit out of reach for first time competitors but was a breeze for more experienced. One did have to be a bit careful on it as the most trivial solutions did not pass.
An error on our part was discovered in testdata for this task. Two test cases were illegal. They have been corrected and the solutions reevaluated a few hours after the competition. Sorry about that.
The fastest correct submit for it was 15:55 after the competition started. Quite a change from 1:26 and 2:00.

TASK MALI

Completely solved by 53 competitors MALI was the second task we deemed hard for newcomers and at least enjoyable for experienced coders. After you get the idea it's not that difficult to code, but at least a few competitors lost points on tricky test cases.
The fastest correct submit for it was 6:29 after the competition started. One of those competitors that skipped the first two tasks, maybe?

TASK GENIJALAC

Completely solved by 53 competitors GENIJALAC appears to be just as hard as MALI. But looks can be deceiving. GENIJALAC is A LOT harder. Solving it required a good idea, and coding it is not trivial. It was also much harder to score points with incomplete solutions.
The fastest correct submit for it was 50:41 after the competition started. A bit fast for the fifth task.

TASK ALADIN

Completely solved by 0 competitors ALADIN is the task that broke the best. Included in the first round to offset the other 5 easy tasks, ALADIN gave the best a run for their money. The highest score was 91 points, by a single competitor. Runner up was on 52 points, also one competitor. 39 points were reachable for much more people. The author of this killer task was Goran Zuzic.
There were no correct submissions for this task. The high score submit was 2:48:13 after the competition started.

by, Marko Ivankovic ( @ivankovic_42 )