# Slovak Camp 2019

Impressions from the Slovak Camp 2019

Johannes Kapfhammer
News

We were invited by the Slovakian Olympiad in Informatics to join their IOI selection for training purposes. From April 30th til May 7th, we thus send a delegation lead by Johannes Kapfhammer and Luc Haller with the participants Joël Huber (Kantonsschule Freudenberg, ZH), Christopher Burckhardt (Mathematisch-Naturwissenschaftliches Gymnasium Rämibühl, ZH), Jijingru Yang (Gymnasium Neufeld, BE) and Rada Kamysheva (Schweizer Alpine Mittelschule Davos, GR). Their impressions of the camp are collected below.

## Monday (Chris)

This year we were going to travel to Bratislava by night-train, so we agreed to meet at the Zurich main station at 21:40. I was excited to travel by night-train, as this was a new experience for me. When I first arrived at the main station I was surprised by two SOI leaders, Stefanie and Benjamin. Both of them weren’t going to Slovakia with us, but had come to the main station to see us off. Together we had a fun conversation about various topics, ranging from algorithms to personal stories. When it was time to board the train, we waved goodbye to Stefanie and Benjamin and began our journey to Bratislava.

## Tuesday (Chris)

We arrived in Vienna early in the morning, where we had to take another train to Bratislava. After arriving in Bratislava we made our way to the university, where all the contests would be held. We ate lunch at the university cafeteria and prepared ourselves for the first contest. After a brief introduction to the contest format, the contest began. Three interesting problems awaited us, with three hours to solve them. The most difficult problem involved both graph theory and geometry. Although it was a difficult problem to solve, the task statement is relatively simple to understand. Given junctions on a 2D plane and roads which connect them, find a path from junction A to junction B, such that the maximum turning angle of the path is minimized. If there are multiple paths with the same maximum turning angle, the path with minimum length should be output.

After the contest we went to the hostel, were we unpacked our luggage. Only Luc had been to Bratislava before, so we decided to explore the city. All the houses were painted in bright colours. When it started to rain we decided to go into a restaurant and eat dinner. By the end of dinner it was already very late, so we went back to the hostel as quickly as possible.

## Wednesday (Jijingru)

In the morning, after a easy breakfast, we arrived the training room, but not in time. So there was no Warm-up any more. The tasks in the morning were not difficult, but very skillful. We had a nice lunch in the school dining hall. It’s lucky that I successfully got white rice for my lunch. Yummy! The tasks in the afternoon were even more difficult. One of them looks like Computing Geometry, but in fact it’s only need a math skills to make it easier to solve. For us, these tasks were very challenging.

After that, we went to the old town to have dinner. It took us long time to looking for the restaurant. On the way to the restaurant, we took a tour of Bratislava Castle. Although it’s very windy, but the view of the castle and river was so nice, especially before the sunset. But it’s unlucky that some parts of the castle were closed. Finally, we chose a local restaurant for dinner, which with a very special decoration. Most of us ordered the roasted duck. Definitely, it can not be the official Peking Duck. It was so huge, but delicious. We took the tram go back to the hotel very late, but we were enjoyed the night in Bratislava.

Group photo at the Bratislava Castle (Luc, Johannes, Chris, Rada, Joël, Jijingru).

“I just want to sleep and wait for another difficult day with horrible tasks.” That’s what I said before sleep. But this prophecy came true.

## Thursday (Jijingru)

Today the tasks were really hard. At first, we used 30 minutes to solve two easy Warm-Up problems on the paper. After that, the contest started normally. I have successfully got all scores in the morning contest. Most of us were very happy, because we got the pleasent scores. But it became bad after a not very nice lunch for Pasta. The contest in the afternoon was really the hardest one I have ever did. I wasted two hours try to solve the easiest one but got nothing variable. After the contests, we were listening to the solutions. For us, these questions didn’t sound very solvable. The main ideas of tasks were 2-Sat, Suffix Array and Nim Game with difficult tricks.

We went to a Pan-Cake restaurant for dinner. There were at least 20 kinds of Pan-cakes, or with Nutella, or with Sheep Cheese. Each of us ordered the Pan-cakes we want. After a enjoyable dinner, we went to a supermarket for shopping. Just buy some bottles of water! Almost everyone returned to the hotel with a box of mineral water. Now our rooms are full of mineral water. This does not look very harmonious, but funny.

Friday was the most implementing day for me. It is sometimes a bit annoying, though this time it was a very good practice. After 7 hours of contest we went to the city center and decided to take pizza and ice cream. We went for a walk in the park and listened to some music, it wasn’t that good, so we decided to go to the other side of the river. There was a very nice bridge with breathtaking view, so we took a few photos and went home to take some rest.

## Saturday 4.5.2019 (Chris)

Chris eating delicious chicken wings.

The morning started as always, we woke up at 7 o’clock, ate breakfast and made our way to the university. Today was different though, because in the afternoon we didn’t have a contest. Although I enjoyed the contests every day, it was tiring and I was looking forward to our free afternoon. I was especially excited because we planned on doing an escape room in the evening.

After the morning contest, we decided to go to one of our favourite restaurants and eat pancakes. The cheddar, bacon pancake was without a doubt my personal favourite. This time I also decided on getting an ice-cream milkshake, mostly because it was advertised as being made with four scoops of ice-cream. It tasted just as good as expected. We still had a lot of time before our escape room in the evening, so we went up to the castle. On our way there we passed a huge wedding. They even had live musicians and a few very large cameras. This time the castle garden was also open. The garden wasn’t too large, but it was still very pretty. The castle itself also looked more impressive from this angle with the garden in front of it.

Because we still had a lot of time until dinner, we decided to explore Bratislava some more. The city is a mixture between new glass buildings and old colourful houses. After a while we started to notice a pattern among the colourful houses, every green house was next to at least one orange house. This observation is probably just a coincidence, but on our whole trip we were not able to find any house where this was not the case. For dinner we had decided on hamburgers. From outside the burger restaurant was literally just a door in the wall with a sign above it, but on the inside it was fairly large restaurant. While everyone else decided to order burgers, I decided on chicken wings. The chicken wings were delicious, but it was impossible to eat them without getting your hands dirty. By the end of the meal my hands were full of barbecue sauce. Luckily the bathroom was just around the corner.

Beating the bunker in the escape room (Joël, Johannes, Rada)

It was finally time for the highlight of the day, the escape room. Because each room was only for up to four people, we split into two groups. One was Luc, Yjjr and I while the other was Johannes, Rada and Joel. Our escape room was about a deadly virus, which we needed to find the cure for. After being stuck at the beginning for a while, we were still able to finish the escape room just in time. There were lots of interesting new problems and it was really fun solving them together.