Well, the point of the IB, as the name suggests, is only to instruct. As long as you understand the rules it's done its job. If you want to practice Killer Sudoku, we had a Killer Variations test earlier. http://logicmastersindia.com/lmitests/?test=M201204S (obviously, not with the same variants, but you'll get more familiar with Killer anyway)

Edited by prasanna16391 2012-08-23 10:42 PM

And yes, there is a particular reason to this fact, which is quite obvious : preparing one set of 9x9 puzzles is already lots of work; preparing two, even if the examples are of a simpler conception, means of course that much more work.

Thank you!

Some of the contest puzzles took me more than one week of work. Another reason is that I want to give at least 100% to create the best I achieve from the variant setting. To produce an other 9x9 set for the IB would result puzzles that could not meet my claim.

One remark: In the 'Non consecutive little odd fish killer' (what a name...) you write something abaout the "main diagonals", but it isn't true at all...

Greetings to Hamburg: Jörg

It is true! :-) But in 6x6 it is not possible (I think) to create an non consecutive with not repeating numbers on the main diagonals. That is why I wrote "In the example, digits on both main diagonals may be repeated" as the last sentence in the IB.

Definitely impossible indeed, since 6x6 nonconsecutive sudokus have to obey one of these two patterns :

Superb grids. Its really difficult to set a time for difficult puzzles, because one puzzle may cost you quite a lot when you finish...

Edited by prasanna16391 2012-08-26 4:11 AM

So players who have already participated can freely post about the puzzles / difficulties / anything else about the test, and they are encouraged to do so now, without having to wait till end of the test.

fellas ...got really depressed and dejected solving these sudokus...clearly these sudokus were not meant for beginners or people who have just crossed the beginner stage..the sudokus were in a totally different level to an amateur like me...broke my head over 3-4 sudokus and eventually managed to solve just one though i partially filled the others...could not even get a look at the 41 and the 56 point sudokus...solving these types of killer sudokus makes me think that guessing is not after all a bad alternative ....all in all these sudokus looked insanely tough atleast to me...but nevertheless a good experience!!!

Great. I'll start off by saying, I enjoyed the test as far as solving goes. As for the 3 hour format, well I personally think this would've been great in a Marathon-like format. I solved 6 of the grids in 70 minutes before starting the Non Cons- Odd Fish variant, and I got stuck on that one for the remaining 100+ minutes. In between(after some 60 minutes of trying), I decided to submit the other 6, and then take a break. Got back in 5 minutes, and then completed it with 8 minutes to spare. Totally, 104 minutes.

I'm not saying it was that difficult, I got back and solved it with a fresh mind later and it is just as "easy" as the others. Its just that, out of the 7, I did 6 pretty fast and I feel like thats all been wasted due to the 7th one. I see janoslaw had a similar experience, and maybe Kota too in the middle, I don't know. If this were a single-Sudoku-submit format like Puzzle Marathon, Sylvain and Hideaki would still be at the top, but at least the gap won't be so huge for those of us who just blundered in one puzzle, as we'd still get the bonus for the rest at least. A really difficult set does that, you miss one thing and you end up staring for long spaces of time.

All in all, probably my favorite set of Killer variants ever(which is saying a lot since Killer's my favorite Sudoku variant anyway), but I'm not happy with my performance, and also don't feel like I got full value for it, even though I finished an LMI test for the first time.

@kishy72, Thanks for your feedback. I have no hesitation in agreeing that this is very tough test if you are a beginner or have limited experience with Sudokus.
At the same time, every test offers different experience and I'm glad that you enjoyed the ride.

Full marks to you for such wonderful grids..... efforts put in are clearly visible....thanks for the nice test!!!

Now coming to the difficulty of the grids.......infact non consecutive fish is very difficult compared to the points allotted to it.....atleast i could not crack it till now....i am not able to get the right start....even birds i have to try again....i wasted full 1hour in these two puzzles and achieved nothing....
But getting continuous 3 hrs spare time is really difficult atleast for me.....
But overall a wonderful test.

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)

A wonderful test and such a new experience of different level of sudokus.
I started 1 by 1 and finished first 3 grids within 1hr and now 4grids were left with 2+ hrs to spare.
I then went to "little odd even diagonal" as this is my favourite one and comfortable over that and finished it well.
Then i started "little diagonal bird killer" i immediately figured out which bird has to what total, but then no inch ahead except 2-3 numbers in place.
Now almost 1.5 hrs were left and i then moved to" non consecutive" but stuck for 10-15 min and didnt get anything then i tried "dots killer" again nothing for 10-15 min. basically for almost 2 hrs i was stuck with these 3 grids breaking head to get atleast start at least. Just 5 min left i got dots killer but could not submit it on time i needed just 30 sec more to submit the answer. And "non consecutive" as prasanna said above i didnt think in that way and so was not getting the start. Now will try remaining ones. :)
Nice experience i would say. Thanks to LMI AND Stefan_Heine.
Regarding difficulty i would they were not hard but tricky. Well i am still learning new things so 4 is ok for me or 5(unofficially) :p


Edited by swaroop2011 2012-08-26 4:27 PM

Nice set of sudokus.

My favorite was the little odd even diagonal which has a regular level of difficulty during all the solving. Dots, Non consecutive and birds were more difficult to start but when you find the starting point there is no great difficulty to continue the grid.
For example, when I saw non consecutive, I thought that there was many numbers outside for a variant (non consevutive) which often didn't need many digits to start. That's why I immediately used the sum of diagonals to find L1C1 + L9C9 and L1C9 + L9C1. I think that it was the sudoku I need the least time to solve.

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.

Thanks Prasanna,will try now.

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 :

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.

Heh? I took 104 minutes on one. I win. No one else. No arguments.

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...