There were quite a few comments from our visitors, especially on the Daily Killer Sudoku page, which makes that and other pages load slow. Therefore, I have moved some of the old comments to this new category.
If you’d like to read what other people had to say about our puzzles you may find the old comment by clicking on the “comments” link below or here.
UPDATE (some 5 years later): I reopened the comments on all pages. Feel free to add your comments there, it means a lot to me!
Fdkr, Udosuk
Thank you for your help – puzzles correct – I will try your Excel method.
I ran through this puzzle again last night and noticed a lot of inferences that I had missed in my first attempt, so I finished it in about half an hour. However I of course knew the major fault line in the puzzle.
I have been doing KiMos for about a month now and have many thoughts on them, however I will keep most of them to myself for now, as I know many of you will enjoy starting from scratch. Two thoughts that I will share are: the daily TiKi is much more fun in KiMo mode, and unlike Gaynor I love it when Djape puts up an Easy.
Ever Onwards
Hatman (the second hasher on the site)
Gaynor
I live in Rhode Island (USA). Our winters are usually snowbound, but this has been an exceptionally warm winter (so far), with temps in the 40s & low 50s at times. Today is another one with temps in the low 40s. Will be out there again.
Hatman,
I assume “TiKi” means “Times Killer” ? For a second, I thought you’d found a new daily sources of killers !
I managed to do your puzzle in about half-an-hour. It was fairly straightforward to do – mainly because most of the cages were just 2 cells. This meant that some cage totals were already determined, and also when one of the cells was known (or had a list of candidates), then the other value (or candidates) was also known. Had the cages been 3 or more cells, then it would have been much trickier. Innies/outies are also more restrictive, as we need to have a single innie/outie to be sure of the value, whereas with a normal killer, a pair of innies (or outies) totalling (eg) 3 has to be 1 and 2.
As to the layout, I don’t mind whether the total is at the left or right, as I just wrote it in again and circled it when i knew the definite value. It also made it quite easy to see which cages were still undetermined.
It’s an interesting theory that all valid killers also have a unique modulo solution. It owuld be interesting for someone to prove this one way or another… maybe using one of DJApe’s Insane puzzles !
Downloaded Hatman’s Kimo 1 this morning at about 9.30. Next thing I knew it was 11.15!! Finished! Excellent. Will read others comments on how they solved it, but my major break through, after the top right nonet, was working out that the cage on the bottom of column 8 had to be 4 and 5, and the cage above’s total was 6. Sort of trial and error I suppose, but only as an extension of normal logic. Very enjoyable, would like more of these, please. (I used the format from http://www.members.shaw.ca/fdkr2/ – so thanks for that.)
Don – lucky you! More frost forecast here! Some of my friends did brave the frost yesterday – but temporary greens and no trolleys, yuck.
Today’s Times has a nice example of J-C’s overlap technique (row 5 + col 5):
http://www.timesonline.co.uk/section/0,,18209,00.html
Hi Gaynor
I am still on the ‘normal’ ones, lol.
Pat was in withdrawal as I went away with daughter to a country music festival so he is catching up now tho.
He is a mad golfer too but only plays twice a week.
Adele
Australia
Hatman
When you say you solve the Killers KiMo style do you ‘erase’ the first digit (when 2 digits) before printing? I did that with an old easy Killer, and also moved the remaining digit to the top right corner – a bit tedious but it did take longer to solve, and more interesting.
I also tried the one on http://www.apathysketchpad.com/images/uploads/doublekiller.png I thought I’d cracked it, but no – can’t get the top centre nonet to work ‘my’ way. Back to the drawing board (or else GIVE UP!). Any clues????????
What’s with all the golfers all of a sudden? I play golf too, but because it costs more to have a round (75 pounds) than to buy a full set of clubs (25 pounds – second-hand), my chances are limited.
Mike Japan
Message to Hatman:
We should form a ‘Killer Hash’.
I’ll drink to that.
Hasher
Udosuk
I set up my spreadsheet as you suggested – it works very well for generating a printable format. I would like one for walk-through as well rather than two separate formats, but I cannot seem to workout how.
I will have this loaded up soon with my original, very cumbersome, solution.
As I reformat the others I will put them up.
AFJT – not quite “unique” – I believe that if you create a killer it will almost always be unique in KiMo form. However, I am sure that you can construct a puzzle that is not unique, only I do not have the faintest idea how to do it.
So courtesy of AFJT, HATMAN’s first KiMo challenge:
Construct a unique killer puzzle that has multiple KiMo solutions.
Gaynor – that would be the ideal approach, however I leave them in and approach the solution by eliminating the “wrong” cage sums and marking the correct ones when I have done this. This is because I have been travelling into London for a few days and actually doing them in the paper.
Ever Onwards
HATMAN
Message to Hasher
Not sure the two things mix, anyway after UK Nash Hash in August I went off the booze, did Turkish Nash Hash in October dry (which was somewhat strange), and am still off it. Perhaps this is why I have so much time for samunamupure.
Note Udosuk would fit in at one of my hashes:
http://www.oxfordh3.org/
I am still trying to get sorted out for Chiang Mai – the usual long distance bureaucracy problems – will you be going?
On On
Hatman
gaynor, what was your approach to the apathy sketchpad ‘double killer’ ? so far I have figured out a ’65’ rule – ? i am rather lost.
wait! could the trick to apathysketchpad be fractions??
Cara – the way to start the double killer is to add together nonets 2 and 5 and divide by 2. That tells you that the sum of the 9 numbers is 65. Then you have to figure out what they are. Apply the 65 rule to col 1 and 2 gives you one number. Apply the 65 rule to col 7, 8, and 9 gives you the next.
yeah Frank, I had gotten that far, have 7 numbers filled in, potentially. but can’t quite get it to work, not sure if I “get the trick” … in nonet 3 box, “13” “13” and 6? innie from 41 box would be 2 … leaving a sum of 31 in 11 box and 20 box to be made up from 45789 .. 20 box could be 5,7,8 but 4,9 does not make 11 …. and what to do with 19 box in column 7?
Embarrassed to admit I am struggling with yesterday’s Thinker (44297).
After resolving the central three nonets (1,5 and 8) there seems nowhere to go. Innies/ outies ther are none.
Some trick perhaps? Or am I just thick (don’t answer that)?
onon
Hasher
Hi Hasher ¡¡ i agree with you…. i did the same….. and dont know haw continues….best regards Mercedes
I didn’t have a problem with Thinker (44297), and I’ve done a number from the Sudoku-a-day archive since as well, so consequently I can’t recall how I did it.
However, it might be worth noting that the puzzle is a Killer-X – had you both overlooked this ?
yessssssss of course ¡¡¡ i did
Hi Hatman,
had a lot of fun with your KIMO.
It took me about 2 hours, but after the first difficulties it cleared up.
Has anyone else found the killer sumarai DJ posted this week. There goes the weekend!
All
I will shortly be putting up three new KiMos and my first attempt at the uniqueness (or not) question.
Spiral puzzles: two very simple two-cell cage puzzles that allow you to practice basic techniques.
Miyuki Misawa: an adaptation of her 8 minute puzzle – I have still not solved the original in KiMo format and for now I am only putting up puzzles that I have solved.
Uniqueness: my first attempt failed – this either leads to a uniqueness proof or an extremely complicated solution.
A problem I am finding with KiMos, once you are a bit used to them, is that they tend to jump from being slightly more difficult than the underlying killer, to being practically impossible.
Enjoy your weekend
Hatman
sorry forgot to refer again to the KiMo website
http://www.diceboard.co.uk
Hatman
So is nobody else having problems with todays killer? My coworkers and I have only been able to get 3 numbers … a 1 in the 4th nonet, and a 6 and 5 in the 7th nonet. Hints to continue … ?
Archive suggestion
Why limit to five puzzles? I want to download all of the puzzles that are there, I sometimes don’t get in here and can easily miss puzzles. Is there any harm to having a complete archive since we cannot download the Killer generator software?
Besides, I am sure they are there, you just removed the links. ^_~
Hi Killer fans,
I designed yet another killer. A pretty hard indeed… Some will say darn hard or even impossible ! But it can be solved by logic since I created it by logic 😉
Here is it :
http://sudoku.apinc.org/article.php3?id_article=9
PS Perfect Sudoku confimed it has a unique solution.
Have fun.
Jean-Christophe
Regarding the problem of people not knowing when puzzles are of the ‘X’ variety, I think that it’s down to low-quality home printers. The ‘X’ line is quite faint and it is only visible on puzzles printed on my cheapo personal laser if printed when hot. Most of the time I print ’em cold so the line cannot be seen. Making the line bolder or adding an X to the bottom title (so it says THINKER X) should do the trick.
P.S. DJ’s puzzles are the best!
Richard (UK)
ASTjitters – I’m still wrestling with today’s puzzle, but I’ve gotten further than you. You can use innies-and-outies to get a bunch of pairs that you know the sum in R3 and R7. (e.g. R3C5 + R3C8 = 8) Then look around naked pairs and relationships that give you naked pairs.
At this point, I’ve 5 numbers fixed in N7, 2 in N8, 7 in N9, 2 in N6, and 2 in N3. Unfortunately, at this point I seem to be rather stuck.
I have a strong suspicion that there is something rather fundamental that I am missing. Last week’s Insane puzzle didn’t seem this hard. Anybody else care to share some tips???
-Cindy-
Arg. I hate type-os. That should “that you know the sum OF in R3 and R7” and “R3C5 + R3C8 = 8 )”
Cindy
I hated to do it but I resorted to “Trial & Error”. My first try was to make R3C5 = 3. The whole problem evaporated & was completed easily from that point.
Cool killer, Jean Christophe,
Took about 2 hours !!!
Once again I needed to invent new solving methods to solve your puzzle…
Shai
Jean Chistophe
I’ve just spent 4 hours (my longest time ever for a killer) solving your puzzle. Had to re-start twice. The first 2 times I tried to do it from top to bottom. The last time I did it from the bottom to the top.
Phew! Now for a rest! What?! Djape’s got a weekend killer butterfly X?! Well, who needs sleep!
Mike Japan
Mike Japan
Hi Jean Chistophe,
when I tried to go to your reference I got only:
Fatal error: Call to undefined function: entites_html() in /space_3/bonsaimi/www/sudoku/formulaires/inc-formulaire_recherche.php3 on line 21
Any idea why I can’t open the new puzzle?
Greetings from Germany
zauspon
Cindy, apply 45 rule on row 1 to consider possibilities of cells outside of the 20-cage.
If it help you feel any better, I haven’t finished IQ 396437 yet either.
Bob, USA
Sadly the FTP server went down while I was transfering a critical file. Still down after several hours. :-S
Hopefully the HTTP server is still up.
Here is the link to the puzzle :
http://sudoku.apinc.org/IMG/png/KillerB2.png
Hint on opening this puzzle : Think of the overlap technique… And understand why I prefer to call it “overlap” and not “double count”.
hey j-c,
did your puzzle.. took several hours. took guesses at two points, somehow was right and never had to restart … not sure how i did it, but awesome. i started out by figuring that the 5 border cells in nonet 1 had to be 43 in 6 with one doubled… does that make sense? could have been two possibilities: doubled 8 (in corner) and then some numbers (forget them now) or doubled 9 (in corner) and then some numbers (also forget those!) that was guess 1. guess 2 was that in nonet 4, 9 had to be in top row. very cool puzzle! had to use sum sheet, but that’s ok by me. look forward to seeing the ‘logical’ solution.
Thought Friday’s puzzle (IQ 396437) was excellent! Took me almost two hours to complete. Very difficult puzzle, but it can be solved logically (no trial and error). I started it by splitting the cages in R3 and R7 (should be 3 split cages each in both rows). It takes quite a while to “break through”, though…
Looking forward to Jean-Christophe’s new puzzle, and also the new killer butterfly.
Thanks for the great puzzles!
nd .. where’s your 8th? can’t wait.
Hi Bob,
with your tip, I finished IQ 396437 from 2006/01/27.
Thanks
zauspon
Yup, loved Friday’s IQ as well. No trial and error needed… I broke through after thinking about the 20-cage in the first row, but after spending way too much time down the bottom of the puzzle! Thanks, DJ!
I eventually figured out that analysis of R1 would get me moving again, which is Bob’s advice.
For anyone who is interested, here is my method for solving Friday’s puzzle without doing any guessing.
Using innies-and-outies, you can find a bunch of pairs that you know the sum of: R7C1 + R7C3 = 11, R7C2 + R7C5 = 3, R7C4 + R7C6 = 10, R3C5 + R3C8 = 8, R3C7 + R3C9 = 13, R3C4 + R3C6 = 9.
R7C2 and R7C5 each are {12}, so we have a naked pair for R7, so R7C1 = {67} and R7C3 = {45}, so the 1 in N7 must be R7C2, and R7C5 = 2. The 3 in R7 must be in C4 or C5, so they are each {37}, forming a naked pair, so R7C1 = 6, R7C3 = 5, R6C3 = 1. R8C45 = {48} (naked pair), so R8C3 = 9, R9C3 = 4.
R7C789 = {489}. The 1 in N9 must be in the 9-cage. The 1 in N6 is in R45C9, so R8C8 = 1. R89C9 = {2358}. R8C6 = {56}, R8C7 = {23}. So, the {23} are in R89C9 and R8C7, so they are not R9C78, so the 2 in C8 is in R6. R12C7 = {12} (naked pair), so R8C7 = 3, R8C6 = 5, R9C456 = {169}, so R9C9 = 2, R8C9 = 6.
R12C7 = {12}, so R3C8 = {3567}, so R3C5 = {1235}, but it is in 20/3 cage so it must be > 2, so R3C5 = {35} and R3C8 = {35} (naked pair). R3C7 = 4, R4C7 = 8, R3C9 = 9, R7C7 = 9.
The 9 in N6 must be in the 19/3 cage, so R4C7 = {67}. R6C7 = {67} (so another naked pair), so R9C7 = 5, R9C8 = 7.
R1C189 is 23 or 24, so it must contain 8 and 9, so R1C1 = 9. R1C89 = {6,7,*8}.
The 4 in N2 must be in R1, so the 4 in N1 must be in 18/3 cage, so R2C12 = {45} (naked pair). The 5 in R1 must be in N2, so R3C5 = 3, R3C9 = 5, R2C56 = {89}, R3C46 = {27}. R3C123 = {168}, R3C1 = 1. The 8 in C1 is in R9, R9C2 = 3, 3 in R1 is in C3.
The 9 in C4 is in R9. The 7 in C1 is in R8. From here, it’s a matter of plugging away.
This was a really challenging puzzle. Personally, it felt harder than last week’s insane one, even during the second time I did the puzzle to figure out my solving method for a write up.
-Cindy-
cara: just posted up the much-gestated #8. Have fun! It’s not one of my hardest puzzles, but should still take a little finesse to crack. I look forward to working on DJApe’s newest IQ & the new Godart puzzle, which I’ve been holding off on till I got my own one finished…
& just posted up the FIXED version (found a typo in it). Just in case anyone downloaded it within the first 20-30 minutes after I posted it… Sorry about that!
Cindy – I can’t see how you arrive at “so the 1 in N7 must be R7C2”. Am I missing something obvious?
Phil
After Jean Christophe’s mind-blower, Nate’s #8 was a walk in the park. Haven’t finished Djape’s butterfly killer X yet. Thanks for the weekend extras.
Mike Japan
Mike
how do I get to DJape’s butterfly killer?
Don, try visiting other pages of this site – for example the home page :).
Hi,
Here is a step by step solution to my killer “B2”:
http://www.freesoft.be/jc/KillerB2Soln.html
PS There seems to be big problems with a router somewhere because I can’t access two differents servers since 2 days. And I had to use yet another server…
Phil,
Oops! I arrived “so the 1 in N7 must be R7C2” via logic that works if the 21 cage has 4 cells, rather than the 5 cells in the puzzle. Phooey! I don’t know if I made the same logic error the first time I did the puzzle. Arg, I hate mistakes like this.
-Cindy-
Jean-Christophe,
I’m working through your solution for your B2 puzzle, and in step 15, I don’t understand why you don’t need to consider the possibility of R23C7 = {79} before you move on to conclude that the 7 must be in R23C8. Am I missing something?
-Cindy-