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!
Djape,
Thanks for that – I usually only vist the killer page.
I’m puzzled about the file size issue though. On my pc, png files open microsoft photo editor. When I go to print, today’s killer (and the triple X) appear as very small (3.5 cm sqaure approx), whereas when I open previous killers, then are 11cm square. If I save off the files, and look at the properties, they are all the same size.
To solve the double trouble puzzle I used two 9×9 grids and treated it as two seperate puzzles. I did as much as I could on one, transferred the information to the other, did as much as possile then transferred back etc etc. So, I didn’t realise that opposite ends of 4 boxes must be in the same row. No wonder it was so difficult and time consuming!
Great software and daily puzzles of different varieties. Thank you.
One question: With Perfect Sudoku version 0.4, can I create puzzles with other than the 3×3 blocks? I like puzzles that have odd-shaped blocks in them. I also like puzzles that are 6×6, 7×7, 8×8, etc. Are these possible with Pefect Sudoku? If so, how do I create them?
Thanks for your forecoming response.
Regards,
George
George, with Perfect Sudoku v0.4 you can create classic and diagonal, symmetrical and non-symmetrical Sudoku puzzles in any MxN size, as long as MxN is less or equal to 25. So you can create 5×5 but also 2×12 puzzles for example.
Please provide the solution to the SAMURAI SUDOKU from Friday, 11/18/05, Express/Washington,DC Weekend Lookout section, page E15. Thank you.
I agree with ajft. I use Adobe Photshop elements to print this out and the image was much smaller than usual in the print preview pane until I stretched it out to normal size – then it’s fine. So I don’t have a problem but thought you ought to know there is something different about this file compared to previous ones.
Tried the double – twice – still gone wrong! I much prefer the killers, but enjoy the occasional different one (until I go wrong twice!)
I agree that the puzzle today was much smaller than usual when imported into Corel Draw. It was also not black and white but grey and black so not as easy to see my pencilled numbers, much prefer ‘old’ method. The double puzzle was also grey and black, and very small until enlarged.
afjt, I don’t know what kind of a problem you’re having with today’s puzzle – it’s exactly the same as before.
You should try visiting other pages of this website – for instance, there are a few puzzles under the “overlapping puzzles” section including the “Double Trouble X” puzzle.
There is also “Triple X” posted today.
Enjoy! 🙂
Linda and Annette, sorry for not responding earlier. The solution to the Samurai Sudoku posted in Washington Express will be published this coming Friday in Washington Express. That was the agreement between us and the Express.
There will also be another Samurai puzzle on Friday. Last Friday there was no puzzle because of the Thanksgiving holliday.
Thanks for your patience :).
I’ve just tried a few of the Times Online Killers. Each one takes about 15 minutes, you can’t fill the numbers in quick enough. Thank god for this site which offers a real challenge.
Hi Mr DJ,
Have you or will you be posting a killer samurai? If you have, can you pop on the link.
Thanks
I haven’t posted any killer samurai… yet 😉
Thanks mate, look forward to it when it comes……
I agree w/ Phyllis.
DJ Ape makes the best killers, far more challenging than the Times.
11-29-05 Brain was excellent!
Thank you DJ Ape!!
Too easy today. If you must have ones as simple as this, could we have a harder one as well please?
Ok I knew that there will be complaints that today’s puzzle was too easy.
This is why I just uploaded another overlapping puzzle – this time it’s “Triple Trouble X”, which is different from the Triple puzzle posted earlier.
It’s more like the “Double Trouble X” posted a few days ago. And the “new solving technique” also applies to this one.
It’s quite difficult – I hope you enjoy it!
It can be found on Daily Sudoku page: http://www.djapedjape.com/?page_id=37
Today I had a revelation. Usually, even on the easy puzzles, I use a photo-copied grid with the numbers 1-9 in each square and eliminate numbers as I go eg; 3 would mean I eliminate all 1s and 2s in the row etc. The Times Nov 30 puzzle I did in my head without any eliminations, and in a fraction of my normal time.
Mike Japan
Very nice thinker X again, kept me busy for a -long- while
keep up the good work, dj
The Sudoku Killers here are really great… the normal sudokus are soooooooo boring since I discovered the killer.
But is this really the only place to find them…?
It would mean that I have to spend the weekends without a Killer…?
Keep up the good work…
Ron, originally from Holland, but now mainly living in Argentina and Sweden
Nice site, and love the perfect suduko software. It would be great if the archive for the Killer Sudokus also contained the text file for upload into the perfect sudoku software.
Regards
Michael.
Enjoyed today’s puzzle – must have stared at it for a good half hour wondering if I was going to have to resort to ‘trial and error’ when it clicked – R9C1 couldn’t be 9, and it all followed from there.
Will try your new triple – gave up with the last one, much to my disgust, obviously missing something with that one.
Ron, http://www.timesonline.co.uk has daily killers but they are much easier and also not available at the weekend. Also sudoku.heebie.co.uk has 5 killers.
Mike Japan
I love these Killer problems. I can’t wait for the next morning when I can get the next one. I’m not as efficient as some of the responses I see. It usually takes me 2-3 hours to finish them. Today’s problem had 2 solutions. The 6 & 7 in rows 7 & 8, columns 6 & 7 are interchangeable.
Don, yesterday’s problem had only one solution.
What you are saying would be correct if it were not a diagonal “X” puzzle. But, since Thursday puzzle was an X it must have all numbers 1-9 on the diagonals. One of your solutions doesn’t conform to that rule.
Just received Djape’s killer book. Possibly the best 7 Euros I’ve ever spent. There’s only one insane but plenty of IQs and Brains to keep you going until the cows come home. 10/10,
*****, recommended.
Mike Japan
I’ve been grabbing the killers two-at-a-time to double the fun (although it’s only half as often), and during today’s visit I noticed that the 12/1 killer isn’t in the archive. Or is it and I just missed it?
ZD, thanks for noticing that. I just uploaded Thursday puzzle into archive. Sorry. 🙂
12/2 IQ quite difficult – no innie or outie singles to get started.
Friday 2cnd killer excellent. Got the dust off the brain after an easy week of killers.How about that weekend killer we all need…..
Thanks for the IQ again, solved with some effort…
For those who’re bored without any weekend killers, I suggest they try out ND’s killer puzzles, especially the newly released 4th one… I have to resort to “colouring” to solve it, and would like to know if somebody managed to solve it using “purer” techniques?
http://www.ndorward.com
Udosuk
Do you mean the tough (40 minutes – 4th puzzle) or the deadly (68 minutes – 5th puzzle)?
Mike Japan
PS. What is colouring?
PPS. On Friday’s IQ, was the first number you got 1 in the bottom left nonet?
PPPS. I did a Djape Easy, Brain and IQ today. Buy the book!
Djape’s book, puzzle 90, IQ, took me 2 hours to do!
Mike Japan
Mike–oh, you’re looking at the puzzles from the Times I linked to (their initial article on the topic of killer sudoku with specimen puzzles). No: udosuk’s referring to the puzzles I’ve been designing myself:
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
The last one listed is #4, which is as hard as I can make it; this is for those who enjoy the Insane puzzles on this site.
udosuk – thanks for that link
nate,
hubby has been at your 4 all day. So far he’s finished one of them. He reckons they are real tough.
Do you plan to do more?
Adele–yes, I certainly will be doing more of them, though I haven’t set myself a fixed schedule–it’s just whenever I have an idea & start working it out on paper, usually lunchbreak at work when I’m bored. I started creating them because I finished all the Tough, Tricky & Deadly puzzles in the Times book & so was looking around for what to do next. Also, I wanted to make puzzles that would require more advanced/oblique techniques, some of which I’d come across via this site’s puzzles & discussions. Puzzles #3 & #4 make use of a divide-&-conquer strategy for combinations that I generalized from one of udosuk’s posts. Puzzles #1 & #2 are bagatelles based on the “plus-minus” technique that I’ve set out at the bottom of the “tips” page on my blog. I have been working gradually on trying to eliminate “dominoes”–2-cell cages–from the puzzles in order to keep them equally difficult all the way through. (Otherwise, once a few numbers are filled in, the dominoes tend to be easy to solve, & the puzzle quickly cracks open.)
One thing I like about these kinds of puzzles is that their interest doesn’t die once they’re solved: in point of fact I often like to re-solve puzzles to find more efficient routes to their solution. The best puzzles are like good films or chess problems, you can watch/do them many times & still be gratified.
Nate, well said about the resolving of puzzles… I like to redo quality puzzles to and refine the solving process. I might write a detailed walkthrough on your 4th puzzle later… So did you find the steps to solve it with simpler techniques?
Answering mike’s questions:
Main one: Nate has answered for me…
PS: AngusJ’s site (http://www.angusj.com) should provide enough info…
PPS: I couldn’t recall my first number, just did a whole lot of eliminations until I found some cells to fill in… I’m sure with some time & effort you’ll conquer it no problem…
PPPS: Too many “free” puzzles to deal with these days (plus a heavier workload near X’mas time), so I’ll pass the book. But I’m sure it’s a marvelous book and anyone’ll enjoy it!
Nate
Your puzzle #4 was very tricky, but I solved it (took all day) with only a pen and paper and NO guess work.For me there were 2 crucial moves. Firstly, realising that the 23 (row 1, top right nonet) had to be 123467. Secondly, I created a new cage in the top centre nonet of r1c5, r2c5, r3c5 and r2c6 which equalled 22. This enabled me to eliminate 9 from this new cage and it also meant that r1c4 had to be one less digit than r3c5.
I’ll give the others a go now.
Cheers
Mike Japan
Just solved Friday’s IQ. Failed dismally first time but sailed through on the second attempt. I really enjoyed this one; you really had to think laterally. It took me ages to get the first number but after that it was plain sailing. Is the book available yet???
I can solve all your killers (including Insane) in 2 hours maximum. But your latest brain from 11/29, oh man, it took me ages! Djape, congratulations from my wife, you indirectly solved our arguments about the TV show to be watched in the living room…TV, what is that?
Hi!
I love your Killer Sudokus, I’ve been an almost daily guest since October twentyfirst.
I have been waiting for the solution to the overlapping puzzle trouble20051130_2, but now I can’t even find the puzzle any longer. Are you going to file them under overlapping puzzles?
I will answer your overlapping puzzle question when I have tried them all … :o)
I look forward to the PDF-version of your book, (will it be announced in the Shop?)!
Thanks for your excellent puzzles!
Karin
Phyllis
I gave up on waiting for pdf and contacted Luis at
viaoptima@mail.telepac.pt
I think Mike posted the link a while back – easy to do I just paid paypal and am now waiting on it to come.
Thanks for the new Double Trouble X… but I couldn’t find the solution to the Triple Trouble X posted on Nov 30 (as a “Daily Sudoku”)… could you kindly post it up please? Thanks DJApe!
Udosuk, I uploaded the Triple Trouble X puzzle and the solution to the Archive (under “Sudoku”).
Karin, I uploaded the Triple Trouble X puzzles and the solution to the archive
Hi,
I have a question about the rules of killer sudoku. I understand that the numbers in the oddly shaped areas have to add up to the total given there. Is that all or is another constraint that within such areas numbers also have to be unique? Theoretically, if such area stretches over more than one box/row/column it could contain a certain number more than once without violating standard sudoku rules.
All your killer sudoku puzzles over the last couple of days had a unique solution without applying this additional rule, but todays (Dec 7) one has not.
Thanks,
Gnatzkopp
Gnatzkopp, there has been a lot of discussion on the same question that you asked, both here and on other sites.
The general consensus is that you CANNOT repeat a number within a cage. Certainly the solutions to the puzzles that we post on this site must conform to that rule.
It is possible that there could be another solution if you don’t follow that rule.
I will update the top of this page to make this clear.
I seem to have found multiple solutions to this killer puzzle.
The UNIQUE one that perfect sudoku gives, plus these two.
Since I’m probably wrong, please point it out to me! (I can provide a screenshot..)
834125697
796483152
251679348
165397824
329841765
487562931
543716289
918234576
672958413
834125697
796483152
251679348
465397821
329841765
187562934
543716289
918234576
672958413
Cancel my previous. I’ve just seen that I have 6 twice in the 18 cage!
In the reply to Clive, you mention plans to update the top of the page. When you’re making changes, may I suggest you remove the date “October 3, 2005” which seems to be a permanent fixture above the words “Daily Killer”?
Once again, THANK YOU for great killers.
Same as Clive, (ref: Brain 64791)
I was convinced there were at least two solutions because the r4 c1+c9 and r6 c1 + c9 formed an ‘interchangeable X wing’ where the 1’s and 4’s could be swapped round. I too have a second six in the 18 cage. Sorry for daring to doubt you, Mr Ape.
I did find this one a bit tricky around the middle. The upper and lower nonets came out after a bit of effort but I had to resort to ‘X wings’ to make progress in the middle. X-wings are still a bit tricky for me and like Clive that seems to be where I went wrong. Will try again when I have a couple f hours to spare.