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20 April 2008 @ 09:22 pm
WSC 3 Trip Report - This one goes to 11  
This one is goa-ing to be long, so I'll put it behind that friendly lj-cut.



Prechampionship -

Before WSC2 in Prague, the two most noteworthy things were that, given the national qualifying tests, I estimated I'd gotten 15% better over all kinds of sudoku since Lucca, and that I had really not practiced much before the championship itself as I was finishing writing and digitizing the puzzles for Battleship Sudoku which was due April 1st, during the championship itself.

Well, before WSC3 in Goa, I estimated I was not much better over most variants, but I had focused a lot on my classics and was maybe another 15% improved from last year. A lot of this came as I needed to focus on the USSC in Philadelphia and that first prize required classics performance. I also believed, given the tone of an essay from the WPF booklet handed out in Brazil, that a reaction by the Indian organizers would be to add more classics to the championship. In fact, just this last month, I probably did over a thousand TOUGH classics. I completed all 800 puzzles in Peter Gordon's "Mensa Guide to Solving Sudoku" book, completed all 101 puzzles in a number place book from Shinichi Aoki that I got last year, as well as maybe 25-30 remaining puzzles in another number place book edited by Tetsuya Nishio that I got last year as well. Vincent Riviere, captain of the French team, had been asking me for a lot of solving times throughout the year and had given me pdfs for some of his sudoku ultra puzzles et j'ai fait deux cent (six ou sept etoiles) sudoku aussi. Given the subtle differences of various puzzle sources, particularly hand-set versus computer-generated puzzles, I wanted to be battletested on anything I could see.

I had gotten tremendously comfortable with spotting both naked singles and hidden triples with my note system, accepted the $10,000 strategy of uniqueness as completely fair and do it without second thought now, and had further pushed back the line of where puzzles are too hard for me to solve in competition without bifurcation (guessing). I'd also, over the course of my Stanford video project, standardized some of the rules I'd been subconsciously using to get started in the puzzle and my new focused chute scanning was giving me quicker starts on a weakness of sometimes not getting "easy" placements.

However, to cover myself in case organizers took the difficulty of a sudoku to 11, I'd set my own standard of a "one-minute rule". If I felt I had not written a meaningful note or placement in a minute (most likely if you watched me thirty seconds as my sense of time is greatly slowed when I'm focused on a puzzle), then I would jump into a bifurcated track at a spot where I felt I would reach a contradiction soon or have the solution.

Overall, I felt more than ready for the championship. We had a strong team and I hoped for 1st.




Travel to Goa -

Having toughened myself with the hardest sudoku I had at hand, I saved a Geikakara sudoku book from Nikoli (their "very spicy" books) for the plane and pre-championship warm-up as well as a fresh copy of all the Indian puzzles to get back into a comfort state with their setters (all the puzzles seemed hand-set in my mind so specific practice with their constructors was key). Now, the Nikoli books have never given me a hard enough puzzle that I couldn't crack it logically. However, in general, if I spot their gimmicks soon enough, I can tear apart a puzzle real fast. I'd love a championship to be at the Geikakara level of difficulty. You'd see a lot of puzzles like puzzle 8 in the Stanford series - a hard puzzle that logic can trump bifurcation any day of the week and I may be even a minute or three clear of anyone else still.

My trip to Goa began with some anxious moments. A late trip to Fry's to get a fresh toner cartridge and power converter made me miss my ultra-conservative Caltrain that would have gotten me to the airport 2.5 h in advance. I caught the next train, but it had doors that wouldn't close right and, after it arrived 10 minutes late to my stop, it proceeded to lose another 3 minutes or so at each stop between there and the Millbrae BART connection. While I got through the BART efficiently, and ran through the international terminal to the British Airways desk, I was only 55 minutes early, closer than I'd want for an international flight. I fortunately still made my first 10+ hour red-eye flight and was on my way, eligible to defend my title.

I learned over this trip that I'm an aisle person. I maybe learned this the hard way after 5 window-seat and 1 center-seat experiences, but I really don't mind being the person who has to get up so you can go to the restroom. I do mind, when the person next to me is asleep, waking them up to get out to use the restroom myself. I cherish sleep - and rarely get any on a flight - so some part of me cannot wake someone up who is trying to get rest. Further, on those red-eyes, I hate the moments when the whole cabin is dark and you have to decide if turning on your reading light would wake up several around you or not. Again, I lean to betterment of others over my own satisfaction - I have a weird collective good utility function I suppose - and so I'd sit in the dark trapped in the center/window seat watching the in-flight entertainment.

I did get through some episodes of Extras which I hadn't seen before and some other more British entertainment that I hadn't seen. Still 10+ hours is a long flight, and then I had 9 hours to wait in Heathrow. I quickly got myself from terminal 5 to terminal 4, my ultimate departure stop, and found some power outlets to make the wait bearable. During that time, I finally finished "The Walmart Effect" by Charles Fishman which I highly recommend as a fair, but factual, analysis of the effects a massive cost-cutting store like Walmart has globally on suppliers and consumers. I read a good third of an instructional Bridge manual that would help me play bridge with the rest of my US team (when we weren't playing Race for the Galaxy), and also breezed through the Indian tests again.




Finally, my second ~10 hour flight, another red-eye, from London to Mumbai. Some of the German team had flown west to fly east so I was not alone, but my supposed SFO-based US partners Nick and Wei-Hwa, who all had different flights out to get to London, all had different flights out of London within a half-hour of my departure time and so none of us were together yet. A whole extra hour was spent at the gateway after we had planed before we taxied. Again, the window seat was not the smartest choice for me, and the in-flight options were more limited, so I got to see that Book of Secrets film a couple more times.

Arriving in Mumbai gave another chance to stretch the legs, and a first feel for the heat and humidity of India in April. An hour-long coach ride got us from the international terminal over to the domestic terminal where I finally rendezvoused with Nick and Wei-Hwa for the hour connection to Goa. The most noteworthy spotting at that airport was a bookshop named "Crossword." I make a habit of not taking photos in airports as a means of not getting arrested for security reasons, but this was one of two airport sightings I wish I had taken.

The Jet Airways flight from Mumbai to Goa amazingly gave us a meal even though it was one hour long, and service started early with a lemon juice drink that could have stood just sugar or just salt but not both. Nick and Wei-Hwa and I discussed some of their recent events (they had just done the Gathering for Gartner 8, and Wei-Hwa was coming from Mensa Mind Games, we'd all done Midnight Madness) and other puzzle-related matters. 36 hours after leaving my door, we finally landed in Goa, but still had an hour bus-ride to get to the hotel, and with the drastic changes in speed to avoid road bumps (seemingly meant to slow traffic so you'd have to stop near street vendors, although that might be correlative and not causative) and oncoming traffic that decided to pass in our lane of a super narrow road, we arrived at the Holiday Inn Resort in Goa.




The hotel was a welcome sight. After I got my red dot on my forehead when entering, I joked it would last about five minutes as I was going to instantly shower and change clothes after so long traveling. However, as we left our passports at the desk, we waited for about an hour and a half to learn the fate of our rooms. Apparently, the hotel was overbooked and even some of the rooms that had been arranged for us were unavailable for maintenance reasons. We learned this first from our US teammates, not the hotel staff, as Will had sacrificed the single he couldn't get to add an extra bed into Jason and Jonathan's room. As we were sitting, the hotel manager came over and asked "could you sit down so we could talk". I answered - "I am sitting" - but he meant for me to go somewhere else with all the others without rooms. He had the bar bring over some water and beer, proving we were entering a quick and power-less negotiation mode. Fortunately, for the ~9 of us across many groups including the US, Japan, Germany, and Belarus, they would only not have rooms for the first night (after which everyone got into the Holiday Inn). More fortunate for us, they actually had one unassigned double and since Wei-Hwa and I were the only two expecting to get a double and not a single, we took it. It lead us to what we'd call "Cell block E", room 190 over in block E which is not pointed to in any of the signs unless you know it is in a house on the edge of the property in block E. Cell Block E became the most memorable way then to describe where we were. It was a nice room, and we kept it rather cool. It had a candle in the bathroom. I find this noteworthy. Wei-Hwa finds it noteworthy and usable and lights it each day, although I did use it once in this way, checking an unexpected item off my list of things I'd never done in a bathroom. There is a single big bed and we manage to share it without disturbing each other.




A quick shower and change into my Philly sudoku tourney t-shirt (they did sponsor my travel, so they deserved to be captured in the first wave of fan photography at the championship), we headed outside for the welcome dinner and reception. A band covered some bad eighties anthems while we dined on some mostly Indian (some Chinese) cuisine. Overall, the Indian food throughout the championship was good, buffet-style, and with many meat and vegetarian choices, just as I'd expect coming from Cambridge where some iBuff was always a weekly lunch. Wei-Hwa ended up a bit disappointed that the dishes weren't more "authentic" than what you can get in the states, but I'm glad to have palatable meals that do not make you ill when traveling abroad. Oh, and they had ice cream every meal. Even when it was outside in the heat. A special server would carefully stand and close the ice cream vat except when it needed to be served from there. The buffets also had a great selection of fruits made even better on the last night when a fresh fruit choice was there and I could watch a whole pineapple be sliced in front of me to my delight.




After dinner, an instruction meeting continued. I didn't have many questions that would be answered there (although I was desperate for any information on what the playoffs would entail, what the format was, even what the puzzle(s) might be). So, I solved my Nikoli book. Tetsuya and the Japanese team sat around me and Tetsuya and I would discuss in his limited English how easy the puzzles in the Nikoli book were compared to his. He kindly left me two more of his books and shared with me some of his pennames in Japanese so I can recognize them when I'm solving the books. Given how good they were as practice before this event, these books are "gold" for future championships. I also got red-magician, who was actually on the Japanese team, to point out one of his puzzles in the Nikoli puzzle book I was solving. I saved it for the next morning at breakfast but it was a good sudoku puzzle, fair but difficult with some nice placements. I did notice though, as I was solving puzzles next to the "Godfather" of sudoku, that I was making careless errors on the puzzles a fair bit, and actually erased through to the end of the one pencil I'd brought to the instruction meeting so I'd be forced to stop before going on. I hoped this wasn't a portent of things to come.

A mostly restless night led to breakfast before the competition. Wei-Hwa had constructed and brought with him a brilliant manipulative puzzle (to form a 9x9 colored square) from an idea someone else had shared with him. It seems hard but has a bunch of simple ahas you can either discover or be told to break into it. I'd been a bit spoiled in that I overheard the main goal I was meant to do from him as he described it to the Japanese, but I set over breakfast working it out as Nick asked yes/no questions to try to get what the rules were. The yes/no questions were not working well for him, but I eventually solved the puzzle, got out my camera to take a picture, and then started practicing sudoku to get warmed up.




We gathered our things to get to the test room and I took a seat in the back, near Hideaki Jo and Daisuke Taike who I expected would be rather competitive to give me a good time-sense in a round of how well I'd done. Nick came over to ask for my camera since he hadn't brought his and wanted to do team photography. I searched and searched and searched but it wasn't in my bag. I ran over to breakfast but it wasn't on the table. As the organizers were handing out booklets and Round 1 was beginning to start, I could not help but think "S%$^" in some part of my mind that I'd just left behind a $500 camera, let alone the sole chance to have good photo-journalism from the event for the US team.


Individual Competition:

Round 1 - Welcome Round
Score (315 of 450)
Placement (3 - 20 points behind leader)
Puzzles Broken while solving: 2 (Even, Pencil Marks)
Outstanding Puzzles: Outside Sum, Pencil Marks

Round 1 was a welcome round and I expected simpler puzzles to serve as a warm-up. I was not performing well at the start though as I proceeded to break the even sudoku in the first three minutes. Pulling out my big eraser, I cleaned the whole grid. I jumped down to the alphabet sudoku before redoing the even to clear my mind but that puzzle was hard too. Eventually, I got through that page and then got through the next as well. The Outside Sum did something nice that I'm not sure I've seen a lot before - giving you 2 of every 3 sums per box. This means it gives you 3 of every 3 sums really, but you have to work a teeny bit for the third. Four puzzles down, I took my first peak at the Pencilmark Sudoku which is a type I've done twice before including the one instruction example. This one took forever to get started. I hoped desperately that the cool "3" that was not in pencilmark space might be a "meta"-placement number to keep in mind. It did get me a 3, but soon after the 7's and 3's I was working with collided and about 30% in I was hopelessly busted. I did the Numeral sudoku but it took awhile and then with ~3 minutes to go decided to try to power through the 15 point classic at the back to get some value from the time since the Pencil Marks couldn't be fixed in that time and then proceeded to not even finish that puzzle under the wire. Not a good start. Fortunately, the attitude in the room (confirmed by seeing what others had written on their instruction sheets as possible scores) showed everyone had a rough "welcome" to India.

Looking around the room, I saw no camera or case in Nick's hand so I assumed the worst. Oh well, its just a camera, and I can certainly get another, but I hate to think that my carelessness got it stolen. I mean, I'd been observing the Indian waiters swooping in at a moment's notice to take your plate as soon as your fork was left unheld on top of it. I should have known better. But no time to worry. The first big round (since there was a classics-only competition) was coming up.



Round 2 - Classics Round
Score (450 of 450 + 45 points of time bonus)
Placement (2 - 75 points behind leader)
Puzzles Broken while solving: 1 (# 10)
Number of times using uniqueness: 3
Number of puzzles guessed at: 5
Outstanding Puzzles: Not sure of any

Its hard to identify outstanding puzzles in a round in which I start at the back, and find my "one-minute rule" triggered and have to guess. And then that guess is wrong and I take the worst of a variance hit. Then that repeats on the second-to-last. While the guesses would sometimes hit by five from the end, my paper will attest to the fact I still have some underlines down there for all of 8-12. So 5 of 12 puzzles triggered the "one-minute rule" of me running out of things I felt I could do before impatience and anxiety got the better of me. Admittedly, I could just not be sharp, and I am currently in a "no sudoku zone" so I won't retest these for another couple weeks at least, but nothing gelled with me here. Fortunately, once I hit puzzle 7 the sudoku got progressively easier and all within my skills and I blazed through the last 7 in maybe 15 minutes to finish with just under 5 minutes on the clock. Learning about all or none bonus at WSC 2, I checked my grids. I found an empty square on puzzle 5 that I filled in, which triggered a second set of checking past my first potential four minute turn in cut-off of bonus, since one careless error sometimes bespeaks another. Having checked all 12 grids by rows and columns (but not boxes, and yes I can check that fast if my handwriting is ok), I turned in at 3:03 remaining. I apparently was the second done in the round behind Jakub Ondrousek of the Czech Republic. I knew him from this YouTube video I found while scouting out my series with Stanford with a solving soundtrack (maybe that's what mine need to up the hit rate), but did not know if he was for real or not.

Seconds after I turned in, Nick walked up to the desk to say good job on finishing and flashed that he had my camera in his hand. I could have hugged him - that was a big save (maybe not as big as the Round 2 arbitration at Rio, but Nick has a way of taking a crappy day and suddenly making it seem worthwhile). This was a weight off my chest, although I was still disheartened to be breaking puzzles and more disheartened that the organizers were throwing many difficult puzzles, both variants and classics, out at us so that this championship would be far from easy.


Round 3 - Odd/Even Round
Score (395 of 400)
Placement (1 - 25 points ahead of Michael Ley of Germany)
Puzzles Broken while solving: 1 (Odd Sum Pair)
Outstanding Puzzles: Odd/Even Sudoku (Ocean/Sun Theme) - maybe my favorite, Odd Sum Pair, Odd Even Sudoku




So the odd/even round was here, another mostly classic-like round with what I felt would be good going-into-lunch puzzles. It turned out to have most of my favorite puzzles of any WSC ever. After hitting the normal odd sudoku, I ran into an Odd/Even that finally made the Blue/Orange coloring make sense. In my first Art of Sudoku post, I included two puzzles that used odd elements as graphically meaningful pixels in either a 1+1=2 or tic-tac-toe based puzzle, combining art and logic satisfactorily. Well, in this puzzle I was staring at an orange (even) sun, setting over a blue (odd) ocean. It was brilliant. The presence of 4/5 odd cells in some boxes would give particular kinds of information. The givens except for one 3 were all in the sky, maybe like clouds, which forced you to work downwards through the geometry into the bottom of the grid where you had just about nothing. I solved at break-neck pace, but this was fun.

Moving on, the next odd/even reverted to the old first WSC style where all the odd/even cells are shaded, although every competitor gave a wrong answer according to the rules as the odd cells were orange, not blue, and even cells were blue, not orange, compared to the instructions. That and the all odd or all even in a box were pretty standard slogs. Then a really fun odd sum pair came up, a type I haven't done too much, but that essentially requires you to place one odd and one even in each of the few 2x1 cages in the grid, and this had a lot of good requirements of using a "where must the evens/odds" be throughout. I busted it, but learned that I'd been too hasty in the box 5 region to assume where the even part went and so I went more carefully the next time and avoided this mistake. A great puzzle. The Odd Even View on the bottom was the most WPC-like of the puzzles here in Goa, but a really brilliant (and new) variant that made it noteworthy. Done with the variants, I did three of the sudoku in the back and then with about a minute left, decided to check the big value puzzles in the front and, thankfully, caught that on the ocean/sun puzzle I was too busy enjoying the picture to write big digits for a 59 pair in the upper left. Filling those two technically blank cells would save me 55 points which getting one more 5 pointer in the back wouldn't have. So unlike last year, I was catching errors. Still, considering my top performance in the round, it is a shame that I didn't get the equivalent of 15 points per minute of bonus like before - I calculate more like 5 points per minute - as I could only solve the back sudoku puzzles at about that rate.


Lunch gave a welcome break from a tiring and tough set of puzzles, but already a noteworthy group of puzzles, for this WSC. It also brought the one instance of chicken tikka masala at the whole championship, which speaks I think to the fact the Holiday Inn Resort caters to English tourists (as well as Russian), since I consider Tikka Masala to be the heart of England's cuisine. Maybe just above crustless half-sandwiches like cheese and pickle in grocery store cold cases.

I switched seats with Wei-Hwa for the afternoon rounds, in part because the cameras/location was bothering him, and in part because I felt the upper-left of the room would be a good change of pace even if the cameras would find me much more easily.



Round 4 - Standard Variations
Score (390 of 400)
Placement (3 - 10 points behind leader)
Puzzles Broken while solving: 1 (Sum/Killer Sudoku)
Outstanding Puzzles: None - okay maybe the diagonal as the only one I really remember, but that was for having the surprise of having just one diagonal constraint, which itself is not outstanding as it makes a variant even more like a classic and isn't that the problem the organizers want to address. An even with one shaded square isn't much of a variant in my mind either (not that that happened in this round).

Standard variations are good for me. This round should have been good for me. It started ok, I blazed through the first two pages, but the sum sudoku broke my heart. I got all the hard work ins, used innies and outies, used creative pairs, got from the lower left over to lower right, up to the top right, and somewhere near the end made an error. Unfortunately, its hard to tell where an error is in a sum (unlike in classics where I am getting error-correction abilities actually), so I had to erase it all and then go through the whole path meticulously again. I wasted easily 8 extra minutes on it by breaking it, and while I got all but the 5 pointers done in the back, this was the one round I should have completed and had time to check and then twiddle thumbs. Inexcusable.



Round 5 - Neighbours
Score (450 of 600 - no group sum, and a 2 cell transposal in a 25 point classic)
Placement (T5 - 40 points behind leader)
Puzzles Broken while solving: 1 (Group Sum)
Outstanding Puzzles: 4 - No Knight Step, Fortress Sudoku [which together comprise my favorite page of the championship], Group Sum Sudoku, Nonconsecutive (although I think I will always call nonconsecutive noteworthy as they are my favorite variant)

This was going to be the tough round. Not only an hour long, but with a lot of puzzles that just always take work. The first sudoku XV was not a trivial example of what is usually a trivial type. I want to build an anti-XV sudoku now to show I can do it. The quad max was actually easier than the example in the instructions which may be the only time this happened the whole championship so its noteworthy. The No Knight Step tends to be a throwaway type to me as its very classic-y and the knight constraint may be used only a couple times. This one used the knight constraint many times. Most importantly, the givens were in the shape of a knight. Its like they read my blog! Wow! I noticed this shape during the competition. I did not notice the one on the bottom, the fortress sudoku, had its fortress shaped like a rook, but it is a great shape and matches the knight so well. I am unaware of the word fortress being used for "castle" in any English speaking language for the chess piece, but fortress = castle works across the language to transition a "castle" arrangement happily for me. It also is a real fun variant that I'm glad to have discovered from forsmarts last year. I think its a Vladimir original, but since he was competing in Goa this was an Indian designer taking his type. It nicely shades some squares which then must have a digit larger than any digit in white that touches it adjacently. I got all but 10 paired cells in rows 4 and 6 placed and was sure it was not unique, until I caught a sneaky 4 fortress constraint that forced 1 solution. Taking a minute in the endgame to spot the 4 was too bad, and a sign my brain might be mush at this point in a championship, but these were great puzzles.

The inequality though gets a huge thumbs-down. I've had long discussions with Wei-Hwa on how to easily express < or > in a puzzle and even among the ways I've seen it, this is hard here. It also was a simply nasty puzzle and unassuring in a real tough round. The nonconsecutive below it was rather fun and nicely constructed with just an X for the givens. I've seen nonconsecutives with many fewer digits, but this seemed to have a really nice flow as you worked counterclockwise around the grid to make progress.



The group sum then took me back to sophomore year at Caltech and I lost my will to continue for a very short bit and needed a break. I even caught a super cool placement by using a "these 4 sums leave these 2 cells to be 11 for a total sum in the columns of 90" rule, but that only got me one 9 and no other sure placements. After 8-10 minutes with just that 9, and no likely good next path, I did a classic to feel better about myself. This is kind of why I like the unlimited time finals at Caltech. Don't like this final - go play video games for 15 minutes and come back. Fortunately I never let 15 minutes become 15 hours as others did over sophomore year, and I did rather well in school, but a break from something kicking your butt is often needed. I actually did all the classics (although, as noted above, I reversed a 4 and a 6 on the big 25 pointer which I didn't check). I then got back to the Group Sum with 8 more minutes left and caught a second magical placement in the center - "well, these two sums share a cell and share a sum of 51. Given the need for 45 = 51 - X + Y + Z, X must be 9 and YZ are 12 in some order. Again, an unusual way to get just one number. Wow. Two ridiculously non-standard work-ins in one puzzle. It simply took me too much time to find them, and I could not advance to a solution before the time ran out in this round even though its only about 10 minutes of work after you found those phenomenal 9s. The Group Sum is a good puzzle, but timed horribly in a round that was already straining my brain to get solved at the competition. My choice of banking all the classic sudoku here and not getting the group sum sooner probably cost me (in my mind) the individual championship given my lack of a classic-sudoku counterpunch. It was a great puzzle meant for an inspired solve. I apologize to the author that I couldn't deliver it here. I will talk it up here though as a worthy foe for the likes of me, and I appreciate designers targeting different competitors with different puzzles.

15 minutes between rounds to 1) find bathroom - AC-room version in cell block E seemed the best choice and 2) forget about that round. The second all-important classics round was coming up.



Round 6 - Relay
Score (300 of 300 - :29 seconds left = no time bonus)
Placement (T6 - 180 points behind leader with a ridiculous 12 minutes (40% of round) time bonus)
Puzzles Broken while solving: 2 (R1-2, R1-3)
Outstanding Puzzles: Concept behind relay 1 (although I'd seen it before), R2-1 by itself

I've wanted a relay for three years at the WSC. The first one at Lucca seemed to tease at one in its earlier promotional material, but it never materialized. I'd love a relay to be used in a horse-race playoff, but a relay everyone sees in a regular round is perfect too. This round had two four-puzzle relays. The first reused a theme I'd seen in this puzzle Wei-Hwa had given (from Puzzler or another sudoku mag) to mathpuzzle.com a long time ago; namely, the givens in 1 were in the shape of a 1 (mostly) which give givens in the second in the shape of a 2, which give givens in the third in the shape of a 3, .... These were somewhat fair puzzles, only 3 ended up underlined on my paper, but I really botched two of them. A careless 2 misplacement on the bottom of R1-2 left me with a clearly deadly pattern that would have a non-unique answer. Checking the 3rd puzzle showed it wasn't going to be fixed by its existence in a relay (although this should really not matter - but you always wonder if the relay resolves non-uniqueness), and then I caught where my error was. I think it took a minute, but this one I fixed without erasing, my one miraculous save of the tournament. R1-3 became a complete disaster though. When you break a puzzle, and it is a guessing puzzle as well, you are totally in trouble. Your contradictions now may or may not be true as you've got an error in the grid. I wasted 6+ minutes before I got out the eraser and cleared the whole mess and began again. Still, I got through relay 1 with 12 minutes left. Ok, time to work some magic. R2-1 had a really nice set of work-ins. I'm glad I took a brief moment to appreciate them, as its a very nice puzzle. By the end, rushing for time, R2-4 became a guess puzzle sooner than it should have, but I finished both relays. A quick check for blank cells and a turn in gave me no time bonus, but thankfully a complete round. With my solid round 2, I could stand to give up ground here in round 6 and still make the classics trophy (even if I was terribly afraid of that trophy given how hard the round 2 puzzles were. I've never won a championship by guessing - although I have lost one by being late and unlucky to start guessing - so I did not like the shape the classics trophy playoff would be taking.)

Just one last round to go, a tough twins round.


Round 7 - Twins
Score (400 of 400)
Placement (1 - 45 points ahead of Zoltan Gyimessi of Hungary)
Puzzles Broken while solving: 0 (A first!!!)
Outstanding Puzzles: Concept behind grading of three of the puzzles (not a puzzle you say? well, it has seemed a puzzle to past organizers), Classic/Irregular twin and Sum twin


I made one mistake in this round. I forgot completely what the round points were for all the puzzles. This was the one variant round without classic buffer puzzles at the back, so I was silly to do a straight forward from the front, I'm-doing-them-all-anyway strategy, as I almost didn't get through them and I spent more time on a 45-point hard sum sudoku when the tough sum > 8 twin at 85 points was actually, by comparison, much much easier.

Still, here the organizers (except maybe on the useless difference 1/8 twins which was effectively, +/- 1 with wrapping, the same grid) did something smart. On the alphabetical substitution, where the grid is the same on the left and right (except A might be 7 or C might be 4), you only needed to complete 1 grid although you'd certainly use info from each. The same went for the classic/irregular and sum twins. If the grids are the same, even modulo some transformation, you should not need to recopy the whole thing to get marks. I don't mean to call out the Czechs - ok I do - but Twins (part 1), Zigzag (part 3), Mirror (team part 2) or how you graded Cross Sudoku (part 3)? Do you get the difference between solving a puzzle, and what you can hand off to you 2-year old kid to "finish"? Thank you Indian organizers for knowing how to grade these twin puzzles! Oh, and also how to write a twin sudoku where the two sides mattered to each other a lot.

Ok, diatribe over.

Difference 1/8 as mentioned above was basically silly but the rest were good. I went through them efficiently, save maybe the sum that seemed to take longer than 45 points was worth as the "easiest in the round", but got freaked out when I realized with 6 minutes left I'd left the 85-point sum > 8 untouched. Fortunately, it was easy, so I got through it with 25 seconds on the clock. Even adding back the 10 seconds I was given when the power went out in this round, I still was just under the wire. Their round timing was impeccable, if I haven't mentioned it yet.

Oh, and that leads to another thing I haven't mentioned, a peculiarity of the time in India, there would be quick but unexpected blackouts. They'd last 1-10 seconds, and then order would be restored to the world. This happened many times during the individual tests, maybe 4 in total and never more than once a round. I wondered to myself what I'd do if that happened during the playoffs. I can see in the dark, but other competitors might not. Then again, the image of the sudoku they are solving should still be in their heads so is lights out = time out?


Individual day over - I was fairly disappointed in the number of puzzles I botched that cost me (8 total over 7 rounds). Maybe I sound like Tiger Woods explaining how his 68 really should have been a 60, how he ground out an okay round to survive on a day that really just meant survival, but I bet the combination of jetlag and lost camera worry and other things was playing a bit of a role in the early going. I certainly was really unsatisfied with my round 6 time bonus (of 0) and unsatisfied I hadn't cracked the group sum during round 5, but I had no round I really bombed (as you can see above - no round I did worse than 6th, and on average my placement in each round was 3 which was better than anyone else by far, even if my gap in rounds 2/6 could not be overcome to catch Jakub Ondrousek for the individual title. I wouldn't know that yet, though, as scores were just being released. Round 1 was out before I went to dinner, played some games of race, and went to bed. But no other scores yet.
 
 
( 5 comments — Leave a comment )
thedan on April 21st, 2008 01:38 pm (UTC)
Question I've been meaning to ask (if you care to reveal): What notation do you use when you bifurcate? Right now I place number-possibilities-for-square (usually only if there's two) in the upper left corner, and square-possibilities-for-number (the 2 goes here or here) in the lower right. I feel like if I guessed in another corner, squares would become cluttered very quickly...
motrismotris on April 21st, 2008 05:13 pm (UTC)
I've hardly perfected the notation, and what I do will sound silly, but I basically write it as a large number with an underline beneath it, as if it were a regular digit (except for that underline). This leads to no question of what the numbers are for a judge and no need to rewrite them. It often means I need to erase over all my notes as well, but that is not so bad a loss most of the time as you often write notes after the guess and may forget to erase those and that will further break the puzzle.

I am considering using a multi-color strategy - maybe erasable blue pen switching to pencil - if it becomes something I need to actually work more on - but hope bifurcating is a rarity in future events.
jdyer on April 21st, 2008 11:35 pm (UTC)
That explains the underline notation in your book for water squares (which I'm still trying to get the hang of).
motrismotris on April 21st, 2008 11:48 pm (UTC)
Well, I think underlining (and overlining) are things you will notice, and notice as different, while still letting numbers in the grid. My dad has described a use of colored pencils for my book and that might be even better although erasures are limited. Come up with your own style, but definitely learn to track ship information versus number information
thedan on April 22nd, 2008 04:41 am (UTC)
I've been making light diagonal lines. It makes it a little hard to see the numbers, but I just can't process the underlines.

I usually draw small circled numbers for guesses if I do... based on your suggestion, I'll probably start using large circled numbers and just erase the circled ones if I hit a contradiction (with an asterisk on the initial assumption, natch).

I don't suppose Jonathan missed the plane back and is stranded in The Country That Will Not Be Named. That would be helpful in June.
( 5 comments — Leave a comment )