It looks like some players, especially the ones solving on paper, are submitting all Sudokus at the end. Please remember that the points are halved after 40 minutes. So if you have solved some sudokus before 40 minutes, it is important to submit them before the 'penalty period' starts.

what is the password for opening the document

It is written in red right below the buttons 'start classics' and 'start variants' after you have hit such a button.

Beginners' November is over. The top 3 Beginners are hjkl18 (Czech Republic), DavidCollison (UK) and lukasz6500 (Poland). hjkl18's highly impressive runaway performance means he now has 2 consecutive top performances on these contests, and will be bumped up to the Seasoners' category because of this. adityasaraf007 had the best Indian performance among the Beginners.

Among Seasoners, jaku111 and Gotroch make it a Czech 1-2, with Kota finishing at 3rd place.

Thank you all for participating, and thanks to Fred Stalder for providing some beautifully constructed grids. On a personal note, the Outside 1-9 theme was my favorite :)

Thanks Fred for writing the Beginners contest. It certainly helps me a lot, when I don't have to write 8 sudokus every month

With a highest score of 110.65 (compared to 126 in Sep / 118 in Oct), this contest was certainly more difficult even for top solvers. Some of the puzzles were time-consuming to fill so many digits (Outside / Consecutive), if not very difficult. The result was not completely surprising, in fact Fred and me were mostly expecting it. At some point before the test, Prasanna even had suggested increasing time limit.

Anyway, the point I'm trying to make is that beginners shouldn't get demotivated if they scored less in this test compared to previous ones.


Edited by debmohanty 2012-11-16 10:40 PM

Just a few words about the puzzles:

Classics: Not lot of things to say. 4th sudoku was the hardest, with a naked single in R8C2. Once this found, it doesn't require hard step, but the logical path is narrow, so it explains surely that some players spent some time on this one.
I hope that you have seen what I tried to do aesthetically on these grids.

Variants: I was asked by Deb and Prasanna to create a 7*7 toroidal, a consecutive sudoku, an outside sudoku and a killer sudoku. After test solving the set, we found that it was a bit too difficult compared to previous tests, especially killer sudoku. I could have created an easier one, but I don't find very exciting to create very easy killer sudoku. In my opinion, killer sudoku is not an easy variant, and even the easy ones, without hard logical step, take some time to be solved. So we decided that I create another variant: It seemed more appropriate to create an easy antiknight sudoku.

Toroidal sudoku: Most of the time, I like to create toroidal sudoku with the same shape for all regions. This is perhaps because it's impossible with irregular sudoku that I find it interesting.
Outside sudoku: I feared that it could be hard to create something aesthetic for this one. In fact, that is the first outside sudoku I created. I didn't want to put digits inside the grid (otherwise, why name it outside sudoku), and I didn't want to have too much digits outside the grid. I decided the 1-9 stuff for the upper side and right side,and tried to have no more than 2 digits for each row/column in the bottom and left sides. This construction has the effect that the end of the solving is the regions 2,3,5,6. The hardest steps here were two pairs (13 in region 2 and 89 in region 6), that make the puzzle rather medium than easy. (The players that took part in the last WSC know that it's possible to create hard outside sudokus !)
Consecutive sudoku: I chosed the theme being my name's initials: FS. I constructed the puzzle trying to have these letters clearly visible, so trying to have the least possible of consecutive digits outside of the digits making the letters. I tried to "push" the consecutive digits in the regions 3 and 7, where I also placed the digits.
The puzzle doesn't need some hard step to be solved, but it is also, as the outside sudoku, more a medium one than an easy one.

Finally the antiknight sudoku. I think it is not hard, but requires lot of placement using the antiknight rule. The hardest step was to find the pair 25 in region 2 due to the antiknight placement for the 5.

I hope every player have fun, especially those who spent lot of time (spending lot of time without having fun is not an ideal entertainment) !

Fred

Reading you would be the author of a beginners contest, I already thought it would be harder than average. I thought the same during solving. I was very much aware of the ability for naked singles, so I didn't find the 4th sudoku harder than the others.

For the variants, I can confirm some bottlenecks you described; the pair 13 in box 2 in the outside sudoku was hard to spot. This one certainly took most time. The consecutive was not that hard. The long series in column 7 provided much info, and the absence of a lot of bars means you often have to place two consecutive digits with one cell in between.
I have almost no experience in solving anti knights. For your test I practised a few, and learned some typical tricks, most of them being elimination steps. That helped, and I found the pair 25 pretty soon.

I had a lot of fun with the puzzles. Also afterwards, when I noticed my relative good scoring. But during the test the same feelings crossed my mind as Deb wrote above.

Anyway: thanks for the test!

I certainly have a tough act to follow in Fred, but I've tried my best to put together a nice set. I don't think it will be quite as challenging in difficulty as November! I suppose if you look at my blog you'll see I haven't posted sudoku variants for quite a while, so it was lots of fun putting some sudoku together for a change. Hopefully you'll see that when you get to solve the puzzles :)

As everyone knows , the grids of Fred shake the neurons .. ....Ah !Ah ! but we like our agitator of brain, of course !!!



That's very kind of you to prepare the grids for (the past) and next Edition of Lmi beginners.
Thanks to the authors , we make progress .
Thank you very much.

Nice clean sudokus, thanks for the puzzles Tom. :)

---------
So 5 minutes 36 seconds is the time to beat.

Edited by debmohanty 2012-12-13 5:05 PM

Nice sudokus, Tom. Thanks !

My pleasure. I hope everyone's neurons have been tickled, rather than shaken, so far :)

Thanks for the puzzles

Nice puzzles! I had a horrendously difficult time with the Outside until I noticed that I had failed to use one of the clues. The classics were all pretty nice puzzles, the no knight was rather clever, and the killer was really beautiful but I think pretty difficult for a beginner contest! It took a while to see how to make use of the layout most effectively.

In first , the possibility of playing online is really comfortable with the zoom , I see as well as a mole !!!
Thank you Deb .
I thought that I had no chance I never play untouch , anti knight and killer , but the grids were very nice , not easy but not too difficult .(I confirm tickles only...Ah!Ah!)
unfortunately about the killer (I confirm more that tickles in spite of 15 in the middle) ..... I close my mouth because I played as a smurfette , to the right ...to the left ....etc but never at the right place !!!!! result.....far too many time .
The classics were great especially the third and the fourth .
Thank you Tom

Edited by distri 2012-12-16 4:23 PM

All of the puzzles were very nice, though I broke the Killer a couple of times, gave up, came back the next day, and solved it. Also, I spent a few minutes staring at a nearly-completed AntiKnight puzzle before realizing that I had forgotten to use the 2 in the bottom-centre grid.

December Beginners' Contest is over now. Passwords removed from booklets.

adityasaraf007 and khuski move to seasoners after Decembers contest.

I guess I'll had some of my own thoughts, as Fred did last month.

Classics: in general I quite like writing easy classics as you can really put a lot of thought into the design. With puzzle #1 I was hoping to get the digits 1-8, rather than 2-9 around the edge of the puzzle, but sometimes it doesn't quite work out like that. #2 featured some diagonal stripes - and this meant there were very few opportunities to put singles into the puzzle. Instead it was more profitable to solve by focussing on one or two digits at a time. This was supposed to be true of #3 as well, but it turned out even easier than that. I was astonished to see several sub-minute solves, with some as quick as 40 seconds! #4 was supposed to be a little trickier, and is based upon a favourite design of mine. I've used it in tests before, and as perhaps die hard fans of my blog will tell you, is (almost) the pattern I used for my first ever puzzle!

Variants: sometimes you just throw down a design and see where it gets you. With the added constraints that a variant can give, you often have a puzzle that needs very little tweaking. You can clearly see this is what I was after with the untouch puzzle. I was hoping not to need those digits in the 5th column, but didn't quite manage it. The killer was my favourite of the lot. Actually I was a little dopey when initially sketching out the cages and left blank spaces at R1C5, R5C1, R5C9 and R9C1. When I came to extend the cages that now contain those cells, I found that the puzzle still solved perfectly well. A pet hate of mine with killers is where you have to do too much adding up. I guess you have to do a bit to get yourself started here with the "cross" in the middle, but I much prefer to rely on logic that involves restricting a cage to a potential set of numbers and then using them as mini extra regions. So once you worked out how the L shaped 16 and 17 cages in the middle interacted, you were well on your way to solving. I suppose the outside was probably my least favourite of the set. I can't say I'm totally in love with this variant, but I tried to give a good clean solve and leave things well presented. The unfortunate thing with this sort of variant is that often you can miss the significance of one particular clue and be left scratching you head for a while until you come to re-examine it. Finally the anti-knight. I initially tried a design very similar to the untouch, but couldn't get it to work. In a fit of desperation (it was getting quite late that evening and i wanted to finish everything off), I had a look at Fred's completed grid from last month, permuted the digits and gave it a rotation, and then sketched out a striking design which I thought would solve uniquely. Without too much tweaking I got what I wanted. There are lots of subtle interactions with the antiknight logic for certain cells in the grid, and so if you knew what you were looking for the solve was fairly straightforward.

Anyhow, I hope everyone enjoyed the puzzles, congratulations to the winners, and my thanks to LMI for giving me the opportunity to showcase some of my puzzles :)

Tom

Thanks Tom for providing a nice set to solve. The detailed post about creating the grids is really interesting and useful too.

Anyway, the top 3 Beginners are zbych (Poland), DavidCollison (UK) and elena_tens (Greece). dp_94 had the best Indian performance among the Beginners.

Among Seasoners, no one got close to the fairly early "time to beat" set by jaku111 (Czech Republic). Timothy (France) and Gotroch (Czech Republic) are the "best of the rest" with 2nd and 3rd place respectively.

Congrats to all the winners, and thank you all for participating. :)

About Untouch Sudoku, can identical digits touch each other "diagonally"?
I can understand it's not allowed (by observing the Example), but I think some "beginner"s can't.