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!
Oh NO! Can’t we just have our daily dose of normal killer instead of this double one?
Okay now – can todays be solved as 2 separate puzzles. I am think of printing it our twice and cutting it into 2. Will it work?
Adele, this puzzle can’t be solved as two separate puzzles. But you should give it a go – everything is the same as usual and in fact this one is fairly easy, you don’t need to do anything fancy.
Don’t be afraid to try the new things 🙂
Enjoy!
Those 4 SINGLE killers were were really fantastic.Found #3 just as hard as 4 if not more so.also not sure about this overlap one but will give it a go.
Thanks dj. Hubby giving it a go now. Had to talk him into trying tho.
Old dogs hate new tricks, lol
Re Gnatzkopp’s question. I’m glad you asked this. For some time now I have been refusing to assume that a number cannot be repeated within a cage which goes across a boundary and I haven’t had to make such an assumption to solve any killer.
For what it’s worth, I see the function of the cage as a clue mechanism not a forcing mechanism. Why should it be necessary to impose an additional requirement on the pattern just because of a certain clue?
This also goes against the principle that you could make any Sudoku easier to solve by adding more clues – if you split such a cage to make it easier this would change the solution. This can’t be right surely.
In any event doesn’t it remove an element of the challenge?
Excellent today – some beautifully intricate innies and outies in the centre four blocks.
As you said relatively easy as the cross was only necessary for the last 1-9 pair.
Djape, as a variation have you compiled any killer puzzles were you only give the last digit of each cage total? (i.e. sum modulo 10) I assume it has already been done, but I have not been able to find any example of this type of puzzle. Have you come accross these?
You said it was fairly easy – too easy, in fact. Happy to have a ‘double killer’, but please make it harder next time – us addicts need a daily ‘fix’ of having to think! Really enjoyed N Dorward’s 4th puzzle – how about one like that on a Friday to keep us going until Monday. Or maybe as an extra one….
Thanks for the new idea of overlapping killers. Will give it a go for sure! But I missed Wednesday’s Daily Killer and to my despair they’re not available in the archive…
Hopefully I could find them in the next visit as the mere thought of missing any single one of your daily killer puzzles makes me shiver…
To Russell and Gnatzkopp, I could understand your desire for a bigger challenge by allowing duplicates within cages… why not make your own puzzles with that property and name them as “murderer sudokus”?
Enjoyed the double killer X. I remembered that where there are 4 nonets the numbers are on the same row in the 2 outer nonets (Udosuk sudoku kudos, UK – this anagram works coz I’m from the UK), so it was relatively easy. I’m really looking forward to our special xmas day insane banzai samurai bushido Honda pachinko sushi killer.
Mike Japan
Just found the Wednesday Brain Killer in the archive! Maybe it was there earlier too but my eyes missed it. Sorry!
Mike – thanks for your anagram… for the ND #4 killer, I still need some more clarification. So hopefully you could help me out there. I’ll post another message there later. Thanks!
Enjoyed the double Killer today – Nice one DJ! Can we have some harder ones please? An Insane Double?
PS I’m still stuck on ND’s 4th puzzle! Think I’ll have to give in and go seek some hints on his site.
My hubby is still stuck on NDs 4th too.
dj – The Lord of the Sudokus book – can these puzzles be done as separate ones or must you do each page by page.
Ta
What are these 4 ND killers people are writing about, are they on another site? If so can you tell me where? Any extra fix for the weekend is desperately needed!
Must say again, brilliant site. Your killers are the best!
Adele, the LOTS book – you should do the puzzles in the given sequence, but if you get stuck there is a list of missing numbers given in the end of the book, so you can continue from any puzzle you like.
Hi Djape,
I find your calculator very helpful in solving killer puzzles and wondered whether you might hold details of each of the numerical options for cages in a form that could be downloaded and printed for use when commuting etc.
Apologies if this seems very lazy of me but sometimes the maths is a bit of a slog.
Kind regards and thanks for some cracking puzzles.
David
I was hoping it was the sort I could tear out a page and give hubby one page at a time, especially when there is none at the weekends.
He hovers over me at the computer saying ‘it must be there by now’.
I cannpt do these puzzles at all and he cannot work a computer.
Sara, here’s the links to the 4 ND killers:
http://www.ndorward.com/blog/?p=64
http://www.ndorward.com/blog/?p=66
http://www.ndorward.com/blog/?p=67
http://www.ndorward.com/blog/?p=69
Enjoy!
Today’s puzzle should probably be rated higher than “IQ” (and you know what that means), but these days I’m reluctant to call anything “extremely difficult” because someone will come up and say “it’s a piece of cake”. 🙂
Enjoy your weekend!
Finally solved ND’s 4th yesterday evening after getting some tips from the messages on his web page – Bob gave links earlier, and assuming it’s the same Bob, it was his tips that really helped!
Today’s IQ looks interesting – much better than so-called Deadly in The Times today.
David
I think this site is what you need
http://www7a.biglobe.ne.jp/~sumnumberplace/31642733/
Where do I find your book????
Is the solution found by inverting the numbers in R2C4 and R2C5, R6C4 and R6C5, and R12C4 and R12C5 valid? If it is, then yesterday’s puzzle has 2 solutions.
You can find the book in Portugal :).
There has been a delay in making a PDF version available due to technical side of things. The PDF book will be available before Christmas, that’s the best I can tell you right now. Hopefully it will be online next week but I can’t promise.
Mayundo, yesterday’s puzzle was an “X”. Therefore, the solution you’re suggesting is not valid.
Re; David’s comment
I developed my own crib-sheet with lists of possible permutations for 3 cages. Then I found the calculator in the archives and cut and pasted onto my crib-sheet – of which I have several prints – I do a lots when travelling.
If you dont have a crib sheet then you will end up repeating possible combinations for numbers over and over again and this is mechanical and not what Killers are for (brain power).
My crib-sheet is a bit hodge podge and scrappy but it is functional. I would be happy to share it, but bet DJ has something much slicker…
Sorry, but I finished today’s quite quickly – no problems at all, just kept going without pause. Enjoyed it though, as I always do (except the really easy ones). Perhaps you could try less ‘couplets’.
I managed to finish your first Triple eventually, but had to resort to trial and error on the second one – should I have been able to do it all using logic?
Today’s IQ was interesting – just finished it, definitely one of the more difficult ones…
Having done quite a few kakoru over the last few weeks I almost (but not quite) have a crib sheet in my head – definitely for the lower and higher value 3s and 4s…
I copied DJApe’s “calculator” to my desktop (well the code for it) and run 3 or 4 copies from there at one time to help with Kakoru & killer…
P.S. loved the double X killer from yesterday, there is a bit of a trick to solving them though, one thing I noticed was that if you have a number on one of the outside rows/columns you KNOW that it has to be on the opposite side row/column too.
(I.e. on the other side of the overlap).
Hi Susan,
Many thanks for the link in your post 22. Much appreciated.
David
IQ took hubby 20 mins today – not very hard at all he says.
Still working in that 4th one.
Do we get a weekend one this time round?
IMHO, a better list of killer cage combos – larger font, no commas – appears on this site:
http://homepage3.nifty.com/funahashi/game/game676e_hlp.html
[scroll down to view the combinations]
Friday’s IQ was relatively straightforward, but puzzle 92 from Djape’s killer book has got me stumped. Four times I have tried it and four times it has all gone pear-shaped in the top left nonet. I will persevere and hopefully finish it, one day.
Mike Japan
RE: my comment #31 -I meant “no addition signs”, not “no commas”.
[my brain was tired at the time of that entry, having just finished Friday’s IQ and apparently having a harder time than Gaynor, Argon, Mike, and Adele’s hubby]
Actually I shall start to call him Pat instead of hubby, sounds much better.
I just don’t want you all to think it is me attempting these ‘things’.
I do not understand them at all.
Re 31, Cheers Bob.
David
Can someone tell me where the Killer book is available. Thanks.
you can find the book in the page of times on line , best regards
Is that DJApe’s book?
Can you access previous comments in this column. I’ve looked at the archive but cannot find them.
Anyone tried today’s (Monday 12 Dec) Times moderate? There are 3 cages of 8 cells, each cage being a 3×3 with one corner removed. I haven’t finished it yet but interestingly I have proved (unless I’ve made a blunder) that the cage which totals 43 doesn’t allow a 2 in the missing corner. This means there must be a repetition in the cage. I thought someone said previously that the Times always sets puzzles where you can assume no repetition.
Are these getting easier or are we getting too ‘good’? Don’t think it’s the latter.
However, still struggling with your other sudoku’s – xwing20051126_2 and trouble20051130_2. Do you have to resort to trial and error to solve them? Am trying not to do that, but am stuck otherwise.
Russell – I completed the Times moderate this morning though it took me longer than usual. A somewhat rare occurrence of the Times Killer taking longer than DJape’s! – today’s ‘Brain’ was not difficult by comparison.
My solution didn’t have any repetition. I don’t have it with me at present but will check when I get home and post again.
Today’s Times moderate took me a while, probably somewhere near their deadly. Actually there are 4 8 cell cages (I forgot the one at the bottom!). 2 of them have repetition. This is actually obvious for the one at the bottom since the cage sum is 41 and the missing corner is part of a two cell cage totalling 4.
I think they must have got their puzzles mixed up, this is nowhere near a 12 minute puzzle, except for geniuses.
not to be one of the complainers about ratings, but maybe you could explain how today’s is a ‘brain’ .. I have had to use pencil marks for some of the Easys before but I did todays in about 20 minutes in my head. I usually try to do puzzles in my head when I think they might be to easy the other way as to make them last longer. This puzzle had good construction but was like a Times moderate I think. Anyway, looking forward to the book!
The Times puzzle of 12-12 doesn’t have any repetition in its solution Russell. You cannot assume that the number that doesn’t go in the 8-cell cage has to go in the ‘missing corner’ because the cages overlap two nonets. In my solution, for example, I have 6 in the missing corner of the 43 cage on the left hand side. I still have numbers 1-9 in nonet 4 and 1,3,4,5,6,7,8,9 in the 43 cage! Let me know if you want me to try and post the full solution. It did take me about half an hour whereas I normally manage them in less than the suggested time so I think it was definitely harder than ‘Moderate’ (not that I’m complaining about having more difficult puzzles in The Times!!).
Bob
Thanks for the link, it really filled my weekend!
Just worried now how I’m going to cope without the extra killers next weekend!
Yes you’re quite right Cathy. Silly me, I was looking at the cage with the extra corner added! I guess what I was looking for was whether I could assume the 3×3 with the missing corner added would add up to 45. I recognised that it didn’t so that the number in the corner would be repeated in the cage, but the cage itself didn’t have any repeat.
Still it took me around an hour. I think I missed a key placement until later on, when I noticed something which had been there a while and which allowed the solution to run easily from there.
Phyllis, previous comments are available here.
There is only about 400 of them. Good luck!
Regarding the book: my book is at the moment only available in Portugal. It will be available online in PDF form before Christmas.
Thanks for your patience.
Pat says the Brain one took him 20 mins. Definately getting easier to do.
Need a challenge guys.