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Killer Shootout — LMI August Sudoku Test #2 — 25th-28th August75 posts • Page 3 of 3 • 1 2 3
@ 2012-08-26 6:44 PM (#8392 - in reply to #8245) (#8392) Top

debmohanty




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debmohanty posted @ 2012-08-26 6:44 PM

Congrats Sylvain for a very impressive performance.
It looks like most players missed the trick in Non Consecutive sudoku - even though it is only 20 points, it is solved by very few players.
@ 2012-08-26 9:51 PM (#8394 - in reply to #8388) (#8394) Top

neerajmehrotra



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neerajmehrotra posted @ 2012-08-26 9:51 PM

prasanna16391 - 2012-08-26 3:27 PM

Neeraj -

I didn't see this till after the test but, its quite easy. Sum up all the given diagonals, and since the main diagonal is 45, all the rest of them should add up to 360. This gives you, for example, R1C1 + R9C9 = 4, because all the other diagonal clues above and below the grid add up to 356. I'm hoping you already figured out that R1C1 is 1/4 (because the 8 clue is either 3-5 or 2-6, which eliminates all those numbers for R1C1)


Thanks Prasanna,will try now.
@ 2012-08-27 12:07 AM (#8401 - in reply to #8245) (#8401) Top

Ours brun




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Ours brun posted @ 2012-08-27 12:07 AM

Of course you are all wrong, since the hardest one was obviously the Dots Killer. I needed 30' to solve it, more than any other puzzle. But maybe that is because it had no solution. I am not kidding. When there are only two options and that both lead to contradictions, there is obviously a problem. And when, after 15', you realize you had missed a third option and that this one also proves impossible, there remains no doubt : there definitely is a problem.

And there was !

There really was a problem !

There was a big problem !

There was a huge problem named me and me needed 10 more minutes to understand that there was a fourth option - a perfectly valid one.

So, a total of 30' on this only puzzle; 64 on the other 6; 2 minutes to copy the codes, and today is not yet the day when I will say :

@ 2012-08-27 12:25 AM (#8402 - in reply to #8245) (#8402) Top

Ours brun




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Ours brun posted @ 2012-08-27 12:25 AM

Disappointment apart, this was a really good test, with some superb puzzles. All of them were nice, but a few were truly excellent. The "Bird" was of course tough but very interesting to solve. The "Odd Even" was perhaps my favorite; as Sylvain said, the puzzle was very homogeneous in its difficulty and the path was very pleasant to discover and follow. No big trouble for me on the "Fish", I did just as Sylvain and summed the diagonals; still, it was probably not the fastest one for me. The "Dots" was nice too; the best proof is that I liked it despite the big amount of time I wasted on it! Just a remark about the "Navigation" : if my memory doesn't abuse me, I did not use the two sums at the top of the grid; only the two at the bottom. They really did not seem of any help to me, so I guess I somehow deviated from the intended path.

Anyway - thanks a lot Stefan. I join Neeraj : it is obvious that you spent a lot of time on this set. Now take some deserved rest.
@ 2012-08-27 12:54 AM (#8403 - in reply to #8401) (#8403) Top

prasanna16391



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prasanna16391 posted @ 2012-08-27 12:54 AM

Ours brun - 2012-08-27 12:07 AM

Of course you are all wrong, since the hardest one was obviously the Dots Killer. I needed 30' to solve it


Heh? I took 104 minutes on one. I win. No one else. No arguments.
@ 2012-08-27 2:28 AM (#8405 - in reply to #8403) (#8405) Top

Richard



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Richard posted @ 2012-08-27 2:28 AM

Little Killers are not really among my favorite ones. I think that has to do with the possible repetition of digits anlong the diagonals, and the 'unnatural' looking to (non-visible) diagonals, instead of the more 'natural' rows, colums and blocks. Whenever possible, I skipped them. So far.
When I saw the IB this week I had two feelings.
1) It is a test from Stefan, who I know from past German Sudoku Championships, so I should give this test a try and
2) OK, I will have to step over my feelings towards little killers and practise a few.

So I did. I found a few older LK's, started practising and found a few tricks and thought of a few other possible tricks. I wrote them down and that was quite a good idea. Pretty helpful for some grids in the test.

Before the test I thougt the 41-pointer and the dots-killer were highest on my 'most wanted' list.
I decided, when I would finish these two puzzles within 75 minutes it would be wise to try to do the 56 pointer too.

But like others, I got stuck in it. The birds-values were easy determined, but after that progress didn't come, so I decided to finish the other grids first. The last 15 minutes I have been busy with it again, but without finishing it.
Now that I am typing this message, I feel I am tired of the marathon concentration.

But all in all I had a good evening, with 6 out of 7 grids solved.

I have one question about the planning of this test. LMI is encouraging unexperienced players to participate and is even organizing beginners' tests. And then one of the first real tests beginners can participate in, is this one with pretty tough puzzles. Is there a reason for this? I guess so...
@ 2012-08-27 4:23 AM (#8408 - in reply to #8388) (#8408) Top

ashar



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ashar posted @ 2012-08-27 4:23 AM

prasanna16391 - 2012-08-26 11:27 AM

Neeraj -

I didn't see this till after the test but, its quite easy. Sum up all the given diagonals, and since the main diagonal is 45, all the rest of them should add up to 360. This gives you, for example, R1C1 + R9C9 = 4, because all the other diagonal clues above and below the grid add up to 356. I'm hoping you already figured out that R1C1 is 1/4 (because the 8 clue is either 3-5 or 2-6, which eliminates all those numbers for R1C1)


Thanks for the hint, now that I tried after the test, it went really quickly. During the test, I just didn't see any way to get started so I didn't even attempt it seriously...

All in all, a really nice test, what I did manage to do was really fun to solve, though I'm still a bit shaky with little killers. I liked having lots of time to solve, as I could just keep working on a grid without feeling like I'm wasting the time if I don't make quick progress all the time.

The non-little killers I mostly just breezed through, with a bit of a hiccup on Navigation. Bird I ended up brute-forcing by bifurcating heavily: The eventual solution was the second try from the third try at the top. Still, it was very well constructed, as the solving progressed very nicely from each try and the contradictions did come up. I was a bit disappointed that it was so easy to figure out which bird gives which sum, though.

Apart from the Fish, I also missed out on the Odd Even. I hadn't thought about the solving techniques properly and ended up having to discover most of them during the solving. When I finally got my act together on that, it wasn't too difficult to solve, but by then I'd already run out of time by several minutes.
@ 2012-08-27 6:47 AM (#8410 - in reply to #8405) (#8410) Top

prasanna16391



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prasanna16391 posted @ 2012-08-27 6:47 AM

Richard - 2012-08-27 2:28 AM

I have one question about the planning of this test. LMI is encouraging unexperienced players to participate and is even organizing beginners' tests. And then one of the first real tests beginners can participate in, is this one with pretty tough puzzles. Is there a reason for this? I guess so...


Well the monthly tests are difficult. While we do encourage players who do well in the Beginners' test to participate in these, it is a big step from being successful at that level to being one of the top solvers at this level. The Beginners' Contest deals with the basics and fundamentals. I believe, if an inexperienced player clears those the person will at least be better equipped to deal with these harder monthly tests, even if not Time-solving them.

The Beginners' tests will keep going every month, and such a good set of grids should not be passed over because of that, so I feel, no better time than now ;) Of course its a tad bit too difficult since we've not yet introduced Killer/LK into the Beginners' Contests, but we can't really change up schedules and what not because of that and we just hope the Beginners who had too much of a difficulty with this one will understand that. If any of them do have a doubt with any grid, they can definitely ask over here.
@ 2012-08-27 4:49 PM (#8418 - in reply to #8245) (#8418) Top

Akuma21



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Akuma21 posted @ 2012-08-27 4:49 PM

Hi, can someone send me dots killer's solution?
@ 2012-08-27 4:53 PM (#8419 - in reply to #8245) (#8419) Top

Administrator



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Administrator posted @ 2012-08-27 4:53 PM

Sent to your registered email id (yahoo).
@ 2012-08-27 5:00 PM (#8420 - in reply to #8245) (#8420) Top

Ours brun




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Ours brun posted @ 2012-08-27 5:00 PM

Oops, didn't notice the answer. I just sent it via PM.
@ 2012-08-27 5:51 PM (#8422 - in reply to #8245) (#8422) Top

Akuma21



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Akuma21 posted @ 2012-08-27 5:51 PM

Thanks! now i understand.... not all dots were given....
@ 2012-08-27 6:24 PM (#8423 - in reply to #8245) (#8423) Top

Ours brun




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Ours brun posted @ 2012-08-27 6:24 PM

All dots were given, but they only applied to vertically adjacent consecutive digits.

Always read very carefully the instructions!
@ 2012-08-27 9:29 PM (#8428 - in reply to #8245) (#8428) Top

Akuma21



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Akuma21 posted @ 2012-08-27 9:29 PM

Damn!! You are right! Thanks for the precisation!
@ 2012-08-28 1:15 AM (#8436 - in reply to #8245) (#8436) Top

euklid



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euklid posted @ 2012-08-28 1:15 AM

I think I am alone with the problem that I had:
I have completely overlooked the "non-consecutive" constraint at the little odd fish killer! :-)
Without this constraint the puzzle was pretty unsolvable (of course :-) although I had counted the diagonals and knew the corner numbers pretty fast...

Could have finished this test but I am happy with my result anyways.
@ 2012-08-28 1:33 AM (#8437 - in reply to #8245) (#8437) Top

Ours brun




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Ours brun posted @ 2012-08-28 1:33 AM

Do not feel alone, I faced the same problem for a few minutes before I got it!
@ 2012-08-28 4:03 AM (#8438 - in reply to #8423) (#8438) Top

Fred76




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Fred76 posted @ 2012-08-28 4:03 AM

Ours brun - 2012-08-27 6:24 PM

Always read very carefully the instructions!
@ 2012-08-28 5:41 AM (#8440 - in reply to #8245) (#8440) Top

Ours brun




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Ours brun posted @ 2012-08-28 5:41 AM

In my case I could just have read the title... but I guess it wasn't written big enough.
@ 2012-08-28 9:41 AM (#8441 - in reply to #8245) (#8441) Top

Administrator



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Administrator posted @ 2012-08-28 9:41 AM

Reminder to Participants


This is a reminder that Killer Shootout has not ended, and you may still participate over the next 20 hours.


@ 2012-08-29 6:46 AM (#8446 - in reply to #8441) (#8446) Top

Administrator



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Administrator posted @ 2012-08-29 6:46 AM

Killer Shootout is now over. Congratulations to Nikola, Sylvain and Hideaki for taking the top 3 spots. Sylvain took 2.5 minutes to check his answers which probably cost what-could-have-been his first LMI title.

22 players finished all 7 puzzles in the allocated 3 hours. Many others submitted 6 puzzles (there are 20 scores of 144, being separated by submission times)

Thanks Stefan for the Sudoku set, and we hope to hear from you about your experience as well.

ETA : Password removed from test pdf file.
@ 2012-08-29 3:30 PM (#8448 - in reply to #8405) (#8448) Top

Richard



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Richard posted @ 2012-08-29 3:30 PM

Richard - 2012-08-27 2:28 AM

So I did. I found a few older LK's, started practising and found a few tricks and thought of a few other possible tricks. I wrote them down and that was quite a good idea. Pretty helpful for some grids in the test.

Some of the possible techniques for the Little Irregular Killer that I had written down were not necessary to use in the test.
Since it is possible to have a nice co-operation between chaos areas and diagonals I have made two puzzles for the puzzle portal Germany in which those techniques have to be applied. The easier version solves much faster if you apply the technique, the harder one is very tough if you don’t apply the technique.
Have fun!
@ 2012-08-29 5:00 PM (#8449 - in reply to #8245) (#8449) Top

RASHI



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RASHI posted @ 2012-08-29 5:00 PM

any1 can tell the solution of all puzzles?
@ 2012-08-29 5:25 PM (#8450 - in reply to #8245) (#8450) Top

Stefan_Heine



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Country : Germany

Stefan_Heine posted @ 2012-08-29 5:25 PM

Thank you all very much for participating at my first LMI Test! It was very exciting to watch what you do. I hope you all liked the puzzles and if there is anything in general, that I could have done better - please tell me so that I can learn from this.

Congratulations to Nikola, Sylvain and Hideaki - you were sooo fast - incredible!

I hope to see many of you in Croatia.

Thank you!
Stefan
@ 2012-08-29 6:00 PM (#8451 - in reply to #8448) (#8451) Top

Ours brun




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Ours brun posted @ 2012-08-29 6:00 PM

Richard - 2012-08-29 11:30 AM

Some of the possible techniques for the Little Irregular Killer that I had written down were not necessary to use in the test.
Since it is possible to have a nice co-operation between chaos areas and diagonals I have made two puzzles for the puzzle portal Germany in which those techniques have to be applied. The easier version solves much faster if you apply the technique, the harder one is very tough if you don’t apply the technique.
Have fun!

I can only advise you to have a look at them; both are very nice, the harder one being truly excellent (and quite tough even with the right technique).
@ 2012-08-31 12:08 AM (#8466 - in reply to #8448) (#8466) Top

prasanna16391



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prasanna16391 posted @ 2012-08-31 12:08 AM

Richard - 2012-08-29 3:30 PM

Richard - 2012-08-27 2:28 AM

So I did. I found a few older LK's, started practising and found a few tricks and thought of a few other possible tricks. I wrote them down and that was quite a good idea. Pretty helpful for some grids in the test.

Some of the possible techniques for the Little Irregular Killer that I had written down were not necessary to use in the test.
Since it is possible to have a nice co-operation between chaos areas and diagonals I have made two puzzles for the puzzle portal Germany in which those techniques have to be applied. The easier version solves much faster if you apply the technique, the harder one is very tough if you don’t apply the technique.
Have fun!


Solved both. Were great fun. Nice usage of the technique. Thanks Richard :)
Killer Shootout — LMI August Sudoku Test #2 — 25th-28th August75 posts • Page 3 of 3 • 1 2 3
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