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World Sudoku Championship 2009

The 4th World Sudoku Championship 2009 was held in Zilina, Slovakia from 24th-27th April, 2009.
Official Website

Download Instruction Booklet (Part 1)
Download Instruction Booklet (Part 2)

Download Puzzle Booklet A: Mix (Individual)
Download Puzzle Booklet B: Symbology (Individual)
Download Puzzle Booklet C: Snowman (Individual)
Download Puzzle Booklet D: World Record (Individual)
Download Puzzle Booklet E: Power Of Team (Team)
Download Puzzle Booklet F: Musketry (Team)
Download Puzzle Booklet G: Relay Race (Team)
Download Puzzle Booklet H: Play Off Extra (Individual)
Download Puzzle Booklet J: Little Final (Individual)
Download Puzzle Booklet K: Nightmare In Zilina (Individual)
Download Puzzle Booklet L: Strategy (Team)
Download Puzzle Booklet M: Semifinal (Individual)
Download Puzzle Booklet N: Final (Individual and Team)

Indian Participants

Team A
Ritesh Gupta (New Delhi)
Gaurav Korde (Mumbai)
Rohan Rao (Mumbai)

Ritesh Gupta, Rohan Rao, Gaurav Korde

Team B
Himanshu Mittal (New Delhi)
Lovely Krishna (Vijayawada)
Puneet Goenka (Mumbai)

Himanshu Mittal, Lovely Krishna Kattamuri, Puneet Goenka

23rd April, 2009
Gaurav, Puneet and I took a flight from Mumbai, while Ritesh, Himanshu and Lovely took a flight from Delhi around 5am to Vienna via Istanbul. All six of us met for the first time at Istanbul airport. We had a Mumbai Indians vs Delhi Daredevils sudoku competition!

On reaching Vienna, we unloaded our luggage at Euro Hotel, and went out for an evening walk. After a long walk down the lane and back, we had a final discussion of the sudoku puzzles and our team strategies followed by lazy 'Good Night's'.

24th April, 2009
We took a bus from Vienna airport to Bratislava bus station (capital of Slovakia) and then took a local bus to Zilina bus station. We stayed at Hotel Slovakia, two persons per room. The room-mates being Ritesh-Gaurav, Lovely-Puneet and Himanshu-Rohan. After relaxing for a couple of hours, we went for the Welcome Party, where all participants are introduced. We received our bags and WSC T-shirts. What stumped me was the large number of comments I got regarding this blog! Now I know so many of you view my blog :-)

The Q & A session regarding the IB wrapped up the day. There were lots of questions and doubts, some of them still unsolved! Some of the rules were unclear, funny and silly.

25th April, 2009
Competition day! It was great to know I was among the best sudoku solvers in the world. This was my first WSC. With all pencils sharpened, and all participants ready to have a shot at the title, the 4th World Sudoku Championship began.

Part A: Mix (Individual)
The round with maximum puzzles and maximum points. These were related puzzles, and most of puzzles were non-unique if solved individually. Many of the big guns goofed up in this round. The puzzles were good, tough and an interesting set.

Part B: Symbology (Individual)
The top 29 of this round qualified for Part H. There were just 3 puzzles in this round, and 28 participants finished 2 puzzles, me being one of them. No one could finish all three puzzles.

Part C: Snowman (Individual)
Personally, I found this the best puzzle of the championship. Many participants completed this linked puzzle before time, but I missed out on Pencilmark Sudoku.

Part D: World Record (Individual)
This round had one Classic Sudoku to be solved in 10mins. The time to beat to have the Guinness World Record was 5m 25s. Vincent Bertrand from Belgium was the only participant to finish it within 5m 25s and he now holds the world record of an amazing 3m 06s. Great speed and accuracy, I guess we all need to learn from him! Have a look at this Classic Sudoku and see if you can beat Mr. Bertrand.

Part E: Power Of Team (Team)
The concept of this part, i.e. one part of the puzzle per person, was quite nice. But the time was poorly decided. 25 of the teams finished this round before time, so, it made no sense.

Part F: Musketry (Team)
Just one puzzle in this round. Each team member gets 10mins on the same puzzle. Sounds easy right?
It was a great performance by the Hungarian team which was the only team to score points in this round!

Part G: Relay Race (Team)
A relay round which did not impress me. Most of the teams were unable to solve the 2nd puzzle, which was quite tough. Many did not even finish the 1st puzzle in the given 60mins.

Part H: Play Off Extra (Individual)
This was the semi-finals for the next round. There was one sudoku to be solved in 15mins. The top 9 qualify for the Little Finals. I completed the sudoku in 11mins but there were 16 participants quicker than me.

Part J: Little Final (Individual)
The top 9 of the previous round fought it out in this round for the Little Final crown.
Jaselsky Pavel from Slovakia was the quickest.

Part K: Nightmare in Zilina (Individual)
This was a tough round. The fact that this round ended at midnight only added to the difficulty.

After a long championship day... it was time for bed... :-)

26th April, 2009
The remaining rounds of the championship took place.

Part L: Strategy (Team)
This was one of the most disappointing rounds of the championship. 31 teams finished 9 out of 10 puzzles. The 10th puzzle (dominoes) was too tough! The Japanese team did wonders by getting two solutions to this puzzle but still failed to get any bonus points due to some silly rules of the championship.

Part M: Semi-Final (Individual)
The top 36 individual competitors qualified for the semi-final. The format of the Semi-Final was very unfair, especially to competitors like Thomas Snyder (USA) who had a big lead over the rest and yet failed to qualify to the final.

We went for a walk around the city with Slovakian girls who guided us. I think this was better than the championship! ;-)

The closing ceremony followed soon alongwith the Finals and some team rounds. 4D Sudoku was the talk of the evening. It is a very interesting puzzle. Only 3 people have ever solved it. Wei-Hua from USA was the 4th person to solve it. He did it in about 1 hour. Want to beat him? Try out a 4D Sudoku.

The top 8 competitors from the Semi-Final advanced to the Finals in which there were two sudokus. A clear winner emerged in the name of Jan Mrozowski.

27th April, 2009
Bags packed, we took a train to Vienna, and spent a day at Hotel Messe. Daniela Perlega, a member of the Austrian team helped us during our journey and gave us some imputs and ideas about how to spend the day. We did some sight-seeing, took a lot of photos, and wrapped up our trip on a good note. We visited an amusement park, a church, the Schronbrunn castle and many such tourist sites.

28th April, 2009
After a long and tiring trip, we took our respective flights back home to Mumbai and Delhi via Istanbul.

WSC 2009
WSC 09 was not a very big success. Some of the rules, were very unfair and silly. The pattern and points of various rounds were very unreasonable. Personally, the championship was not a very good one.

Puneet Goenka, Rohan Rao, Ritesh Gupta, Himanshu Mittal, Lovely Krishna Kattamuri


Individual Results

1. Jan Mrozowski (Poland)
2. Branko Ceranic (Serbia)
3. Robert Babilon (Czech Republic)
4. Nikola Zivanovic (Serbia)
5. Mehmet Murat Sevim (Turkey)
6. Sebastien Leroy (Belgium)
7. Ko Okamoto (Japan)
8. Goran Vodopija (Croatia)

Branko Ceranic, Jan Mrozowski, Robert Babilon

Indian Individual Results

13. Gaurav Korde (India)
20. Ritesh Gupta (India)
25. Rohan Rao (India)
53. Lovely Krishna Kattamuri (India)
71. Puneet Goenka (India)
78. Himanshu Mittal (India)

Team Results

1. Slovakia 1
2. Czech Republic 1
3. Serbia 1
4. Hungary 1
5. Japan 1
6. Czech Republic 2
7. China 1
8. USA
9. Belarus
10. Germany 2

20. India 1
22. India 2

Country Results

1. Slovakia
2. Czech Republic
3. Serbia
4. Hungary
5. Japan
6. China
7. USA
8. Belarus
9. Germany
10. France

16. India

Complete Individual Results
Complete Team Results
Complete Country Results

Congrats to everyone!

Special Thanks to Deb Mohanty and Rajesh Kumar for providing the Indian team with some good practise sudokus.

Looking forward to WSC 2010 in USA!


Tejal Phatak said...

Must have been a wonderful trip and a great learning experience in spite of some of the rules which were disappointing...U guys must have really enjoyed!

Congrats to all of you!!! :)

Rohan said...

Thank You Tejal!

It was a great experience, a superb trip, but a disappointing championship...

karel.jr said...

I have read about part with the world record...

I'm not sure, if there is something else than a tip, what we can learn from him...

This table is completely wrong for the competition which is solve by people... If there will be some for computers, so this puzzle will be ok :o(

And there was more mistakes with puzzles. And if we add the problems with bad rules, we can say, that this championship was poor and it was wasting of time of participants :o(

ZD said...

This was a very nice writeup by you, Rohan. I think you get right to the point about many of the highs (certain rounds, Slovak guides) and lows (team rounds, other rounds). I will finish writing my report and you should read it and see how *not* to write one of these reports. :)

You are right about some people getting tripped up on that first round (myself included), but I noticed that most people figured out what was going on rather quickly. I never really did, and am pretty ashamed. There are other problems with WSC 09, but those don't excuse my laziness here.

It was very nice to meet you and the rest of the Indian team. I hope to see you in Philadelphia!

Anonymous said...

In fact most of the participants are not happy with the unfair and silly scoring rules. Do read the review by Ritesh Gupta, one of the member of India team at .

Also one can download Sudoku made by me for Indian team practice at

akash said...

hi rohan . congrats for your performances in the wsc . thought of writing to you but somehow couldnt write. just wanted to know whether the puzzles in ur blog are the ones that appeared in the wsc ? and also wanted to know how u guys manage to solve the sudokus so fast online? i try doing them online but with each tries i get even more disappointed. i m more comfortable with pen and paper .

Rohan said...

The downloadable pdfs are the sudokus that appeared at WSC...

You can try them! :)

Anonymous said...

Hi, thank you for giving us the possibility to look at the championship it possible to know the maximum time allowed for each round in order to try to see how many of them we can solve in that time? :)

Rohan Rao said...

The downloadable pdfs (which is included in the start of the post) have the timing of each round quite clearly :-)
You can time yourself based on each round time and check your performance with the participants' which you can find in the pdfs in the end of the post :-)

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