UKPA Open 2016: Individual Round

The UKPA Open 2016 was held in Croydon on February 27th-28th. Tom Collyer was the winner of the Sudoku competition, with Mark Goodliffe finishing in second and Heather Golding in third. Neil Zussman won the Puzzle competition, with Tom Collyer finishing in second and Steve Barge in third.

I contributed an individual round for the puzzle event and a team round. This post will contain all puzzles from the individual round. The team round will be posted in a separate post.

Puzzles can be found below.

Puzzle #180: Slitherlink; Filled Loop

This is the eighth practise puzzle for this year's UKPA Open.

This is what I feel is another inherently hard type. So I tried to at least create a few openings that were all based on purely Slitherlink logic. there is a point in the end usually where you aren't as free in choosing your Slitherlink clues as you still need to fit in all pentominos. I think in the end this one gets a bit harder, but if you take into account the "no three can meet" rule, you should still be able to work through.

Rules for Slitherlink

In this Slitherlink the loop has to be completely filled with the given pentominos. Each pentomino must be used exactly once. They may be rotated and reflected. Pentominos may only touch each other by a single edgNowhere do three or more pentominos meet at a point.

Example

Puzzle

14th 24 Hour Puzzle Championship

This year I wrote a set of puzzles together with Hns Eendebak. I was a bit tight on time with a holiday and other championships that I wasn't sure if I'd be able to write everything in time. I still ran a bit late getting everything together but it was in time for the championship.
This year's championship was won by Peter Hudak. Nikola Zivanovic and Zoltan Horvath finished second and third.
There were 30 competitors total in this year's championship, of which 29 did our set. The set was a bit on the long side this year with the Michael Mosshammer from Austria being the top scorer with 695 points. It would have been better if the top scorer had about 100-150 points more. The set contained 24 puzzles in total, so I should have probably cut 2 puzzles in the end.
In this post I will be adding all the puzzles I wrote. You can find the complete set and all other sets here. If you need to see the instruction booklets for any of the set you can find them in this forum post.

Puzzles can be found below.

Puzzle Competitions: ZeKa 2014

Last weekend was the ZeKa competition in Croatia. It featured both a individual and a team competition this year. The individual competition was won by Goran Vodopija; Marko Obradović and Dragan Tolomanoski finished second and third respectively . The team competition was won by Dragan Tolomanoski, Bojana Vojnović and Vanja Fornazar.
I provided one of the Team rounds this time. The theme of the round was Imposters. The round consisted of four classic puzzle types. Each type had 4 puzzles, where one of the puzzles was an Imposter. It wasn't actually solvable as that puzzle type, but was solvable under a different set of rules. The rules of this puzzle was provided. The imposters weren't designed to be logically deduced, but purely intended to break down under the original rules.
The four puzzle types were LITS, with Double Back as imposter; Shikaku, with Corral as imposter; Skyscrapers with Haido as imposter; Slitherlink, with Turning Fences as imposter. Two of these combinations have appeared on my blog as a Double Trouble puzzle. One of them appeared as such on Grant Fikes' blog. The other is probably possible as a Double Trouble puzzle, but haven't tried that yet.

Puzzles can be found below or in the following PDF.

Czech Team Puzzle Championship

In the weekend of 7-8 September, the Czech Sudoku and Puzzle Teams Championships were held. The championship was held in Brno. The teams competed in a number of team and individual rounds over the weekend. The Sudoku event was won by the team of Michaela Bieliková, Matúš Demiger, Zuzana Hromcová and Jakub Ondroušek. The puzzle event was won by the Hungarian team of Zoltan Horvath, Pal Madarassy, Major Boglár and Zoltan Nemeth. Full results can be found here.
All Sudokus and puzzles of the championship can be found here. I also provided some of the Sudokus and puzzles for that event. This post will contain all my puzzles.
All my puzzles featured in a single round, together with 2 other puzzles. I hadn't written these puzzles to be a complete round and just wrote a number of different puzzles. It was Karel's idea to use them all together. I chose to write a number of common puzzle types, a number of uncommon and a number of variants of common types. So it's a good mix of puzzles to be featured in a single round. They are mostly puzzle types I had written before, so I knew what to do with them. I'm happy how they turned out and think it was a good mix of easy and hard puzzle.

Puzzles can be found below.

Polish Puzzle Championships 2013

This week is a week full of puzzles on my blog. That is because the last two weekends there were two championships to which I contributed puzzles. Today I will post all puzzles from the Polish Puzzle Championship and Thursday will feature my puzzles for the UK Puzzle Championship.

The Polish Sudoku and Puzzle Championships were held in the weekend of 9 and 10 of March. Jan Mrozowski became the Polish Sudoku Champion. Przemysław Dębiak won the Polish Puzzle Championship. The puzzles for the Polish Sudoku Championship can be found here; the puzzles for thePolish Puzzle Championship can be found here. My puzzles were round 5 of the Puzzle championship. I also found a video of the Polish Puzzle Championship on Serkan Yurekli's blog. In the beginning you can see puzzlers working on my puzzle set. The end is the finals.

For the Polish Championship I employed a copycat theme. The puzzles came in pairs and each pair of puzzles had a similarity in the layout. Most of these types are very closely related in the puzzle type. The only pair that really isn't very close to the other were the Star Battle and Heyawake. I was happy to see that the puzzles were printed on bordering pages in the puzzle booklet, so solvers might notice the similarity.
The idea somewhat accidentally happened. I had made an easy Akari puzzle and wanted to make a harder regional Akari and opted to make one with the same black squares. When I finished those I wondered if I could keep doing that and went with a Liar Loop/Maxi Loop combo as that seemed most easily acchieved. And I'm pretty comfortable designing those, so made two with the same regions. The next puzzles I made were the Capsules and Ripple Effect puzzles, I posted earlier which ended up testing too hard. I really like constructing Ripple Effect puzzles, but clearly not that skilled at making them competition difficulty. I looked through my Double Trouble collection and thought Turning Fences and Slitherlink should be easily made look similar. I chose the same clue positions and about half the clues are the same. I already had 4 Loop puzzles, so that was all of those I could put in. I made a Tapa and Nurikabe with the same clue positions. I at first tried to also make the Nurikabe clues to be the sum of the Tapa clues, but that didn't prove to be very fruitful. I then started doodling a bit and made a Small Regions Star Battle and wondered what type I could use these cages for. I eventually settled on Heyawake as that would allow me to add some clues and see where it goes. The regions were still very restrictive on the Heyawake genre, but managed to push it out with just 2013 as clues. Lastly I needed some Magic Square genres. I thought first about doing Skyscraper/Haido, but figured with multiple similar types, maybe I should try a more different type. So I made a Skyscraper puzzle, to which I added a number of clues to turn it into an Easy as Japanese Sums puzzle. I felt I was somewhat missing a division type puzzle, but I couldn't find a nice way to make 2 that fit into the theme. And when I had the puzzles tested it seemed like there was enough to fill the hour slot already.

I also wrote a LITS puzzle to be used for the finals, except that one wasn't used. It willbe posted at the end of this post.

Puzzles can be found below.

Puzzle #67: Slitherlink

And this is the last puzzle that featured in my set of the 24 Hour Puzzle Championship. Somehow I don't see many people being surprised that it is a Slitherlink puzzles. This has always been one of my favourite genres. It just seems to work well with how I like to solve and design puzzles. I decided to make this one on the easier side. A lot of familiar patterns and short term inner loop deductions. It was one of the lower scoring puzzles in the test and meant as a nice opening puzzle to the test.

Rules for Slitherlink

Slitherlink Pattern Guide

This is an introduction to number patterns in Slitherlink. It's not a complete guide to how to solve these puzzles. It's about patterns I think are handy to recognise as it makes solving these puzzles easier. There's a few patterns that are very common, which most people who solve these puzzles are aware of. This is because they show up in about every other puzzle. I like to use the more unfamiliar patterns in my puzzles as it gives people new things to learn. In my opinion it doesn't actually make the puzzles more difficult, just takes more effort to solve as you have to discover the patterns first. If you already know them, they're not actually harder.

Puzzle #51: Slitherlink

After the WSC and WPC my puzzle energy has been really drained. I don't think I'll post regularly for a while. This puzzle is the only puzzle I wrote during the whole championship week. It is meant as a Slitherlink Pattern Tutorial. I wrote is as a response to my teammates asking if there were patterns they didn't know. So I showed a few I like to use in my puzzles. Then I decided to just create a puzzle around all of the ones I had shown. I added one or 2 more little tricks I also like to put in. It's not a complete package of tricks for my puzzles. I have put some others in puzzles too. But figuring out all patterns in this one should get you along a fair bit in my Slitherlink puzzles.

Rules for Slitherlink

Puzzle #49: Slitherlink; Liars

I'm not sure how much I will post in the next week or so. I will be flying out to Hungary on Sunday to participate in the World Sudoku Championships and World Puzzle Championships.

For this puzzle, the opening is trickier than my previous Liar Slitherlink puzzle.

Rules for Slitherlink

As an additional rule, exactly one clue in every row and column is incorrect.

Puzzle #35: Slitherlink; No Touch

These shifted square clue patterns I always like. I've employed it in many puzzle types. It doesn't work for everything as it always leaves a lot of room. With this type it works really well, as the clues give extra information for many of the unclued squares. I think this one worked out well, although the left bottom is tricky.

Rules for Slitherlink

As an extra rule, none of the given clues share a border with a square that has the same value. This only goes for the given clues, not the remaining squares.

Double Trouble #5: Slitherlink and Turning Fences

This combination of puzzles took the longest to get to work out of all Double Troubles so far. I couldn't get the end to work for most my tries. Maybe it didn't help that I was stubborn in wanting to use a preset layout. It's easier if I just place clues where they are needed.
These Turning Fences I haven't really seen many of. The only time that really comes to mind is a WPC. I'm thinking it was in Borovets, but not too sure. I just came to use it again recently and I figured it should be possible to make them looking like normal Slitherlink, so figured it might also be possible for one to actually be a Slitherlink.

Rules for Slitherlink

Rules for Turning Fences

So firstly it can be solved as a Slitherlink puzzle. this puzzle has its easy and hard parts.It still seems pretty typical for the style and difficulty I like to make them.
Secondly it can be solved as a Turning Fences puzzle. This one is about the same difficulty as the Slitherlink puzzle but as its the first on this blog it might feel harder.

Puzzle #24: Slitherlink; Liars

Many people will have seen this variant on Mellowmellon's blog. This was not the first place I encountered these puzzles though. Back in 2006 they appeared on the Dutch Puzzle Championships. We had a short round with 4 of these puzzles. I really liked the idea back then, but hadn't really come back much after that. I found it interesting to see the idea had popped back up afterwards.

Rules for Slitherlink

The clues work as a normal Slitherlink puzzle, except in every row and column exactly one clue is incorrect.

Puzzle #17: Slitherlink/Myopia

This puzzle is a combination of Slitherlink and Myopia, where both types of clues are present in the grid. This combination of these types I tried out for my LMI Hybrids test. I liked how they worked together, but I wanted a bit more of a combination of rules, instead of just clues from both types. When I came up with Pentopia, I figure that was a better use for the Myopia genre than this one.

Rules for Slitherlink

Rules for Myopia

Puzzle #12: Slitherlink; No Touch

Rules for Slitherlink

This puzzle is a variant on normal Slitherlink, which takes a bit from puzzles which have all of a certain number given. None of the given clues share a border with a square that has the same value. This only goes for the given clues, not the remaining squares.

Double Trouble #1: Slitherlink and Toroidal Slitherlink

I've always been interested in puzzles that can be solved under 2 different rules. It won't be a regular feature as I don't think I can pull it off every time I try. It's just something I find interesting and sometimes give a go. There's a lot of puzzle types out there that look the same at first sight, so there's enough options for me to try it with.

Rules for Slitherlink

This time it's two slitherlinks. You can solve this puzzle as a regular Slitherlink puzzle. It's not too difficult, but still fun.
You can also solve it as a Toroidal Slitherlink. Here the edges of the grid wrap around on eachother, which turns opposite edges of dots into the same line. This means the loop can run from one edge and continue on the other side.
Not every puzzle type will give the possibility to create a puzzle that is both regular and toroidal. This one works as in runs over the grid lines.

Puzzle #2: Slitherlink;Toroidal

Rules for Slitherlink

Here's a Slitherlink puzzle with a twist. This puzzle is toroidal. This means the edges of the grid wrap around. The top line of dots are the same line as the bottom line of dots; the same goes for the right and left line of dots. The loop can now run across an outer edge and continue on the other side.

Puzzle #1: Slitherlink

Rules for Slitherlink

This puzzle is a standard Slitherlink. I know I said I would post variations, but I figured I should at least post one normal puzzle if I'm going to post variations on certain puzzle types. This puzzle is anti-symmetric. Every square rotationally symmetric to a 0 has a 3 and vice versa. The same goes for all 1 and 2 clues.

Rules: Slitherlink

Slitherlink is a genre developed by Nikoli.

Draw a closed loop by connecting dots horizontally and vertically. The loop can't touch or cross itself. The numbers in the diagram indicate how many of the segments around it are used by the loop.

Below is an example with its solution.