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!
Zauspon,
Unfortunately, in v0.4 it isn’t possible to save the solving progress of a Killer Puzzle – only the starting position. This is something that I will definitely have to implement for v0.5.
The “Show” frame is used as a helper tool. If you click on “pencilmarks” it will only show the pencilmarks that you made in the puzzle (by right-clicking). If you click on “legal values” it will only show the possible values for each cell. You can select different solving techniques – the more techniques you select the more possible values will be eliminated.
So, for example, if you click on “legal values” and select only “innies/outies” it will show you all “innies/outies” that can be found in the puzzle.
Cheers!
I finally cracked this week’s “Brain” when I realised that R5, C3 had to be 9 (same reasoning as Babs). From there it was plain sailing.
Amazing isn’t it? I did it completely differently and quite complex. Suffice it to say it was deducing that R6C3 could only be 5 or 6 – and testing 6 made things go wrong. So putting in the 5 unlocked everything.
today’s iq is impossible:
6th row – the 10 has to be 46 or 28 BUT in the first block, the 17 is a 269…..
unsolveable?
Cheryl,
you’re right about the 17 and you’re right about the 10, but your conclusion is wrong – what if in the cage with the sum 17 you put 2 in R5C2? The cage with the sum 10 can still be 2+8 in row 6.
Think about it 🙂
Hi djape,
thanks for your answer, but…
I tried my fortune with EASY(6915) from 2005/11/02;
in the design mode I drew the cages and filled in the sums;
so far so good !
Then I changed to the solving mode and put my first pencilmarks and solved some field values regarding innies and outies: okay?
But choosing the legal value option in the „Show“ frame I saw all possible values from 1 to 9 in each field no matter what I did with the field before or which techniques I selected.
Is this normal? I suspect that I only need a little hint.
Apropos hint: this feature the message „the puzzle has no solutions – can’t give you a hint“.
Perhaps an important detail: the elemintion switch isn’t switchable and only in bright grey colour.
Tried a new download and installation of Perfect Sudoku, but no change!
By the way, is there a possibility to load the daily killer for Perfect Sudoko without designing it new?
Sorry for waisting your time but I need some help.
Tschues Zauspon
right. had the 5 no 26 squoint. got it now
Friday’s IQ killer;absoluteley awesome;3 hours 15 minutes.Keep them coming djape.
Friday’s killer in the Times was meant to be a “Tough”, but your “Easy”s are more difficult. How about publishing a killer book for xmas?
Mike Japan
Regarding the Tue Nov 1 “BRAIN” killer X, it’s indeed quite challenging to solve but not too hard. After a bit of analysis I’ve summarised a few key points as described below:
1. Obviously R1C[3,4]=4,1 and R9C[6,7]=9,8. And as djape instructed, innies from R[1-4] and R[6-9] will give R4C8=4, R6C2=3.
2. After some more eliminations, R6C1 should be a hidden single of 4, forcing R7C1=9 (13-cage). Then R[7,8]C3 becomes a naked pair of {7,8}.
3. So R4C[3,4] must be {5,8} or {6,7}. Also, R6C3+R[7,8]C4=(26-7-8)=11 (5 cells 26-cage), so 9 must be eliminated from these 3 cells.
4. With C[1-2], R[2,3,9]C3={1,2,3} (outies sum to 6). Then R5C3=9 (hidden single). This will narrow down many cells in rows 4-6.
5. In particular, R5C[4-7] should be 4 out of {2,3,4,5,6} and sum to 26-9=17, which must be {2,4,5,6}, forcing R5C7=6 and R4C6=3 (naked triple).
6. Similarly, a few steps later the 17-cage up top should be 3 out of {2,4,5,6,7}, which can only be {4,6,7}, and that cage should be solved immediately.
From that point on it should be very straight forward using the diagonal property.
I’m proposing a trick which I think many players already knew, but I’ll formalize it here anyway. I call it “subtraction combo”.
For example, in step 5 above we narrow down R5C[4-7]=17 to be 4 out of {2,3,4,5,6} which sum to 20. Since 20-17=3, 3 must be the odd candidate out, leaving {2,4,5,6}.
In step 6, a 3-cell 17-cage must come from {2,4,5,6,7}, which sum to 24. Since the 2 odd ones out must sum to 24-17=7, which can only be {2,5} here, we must have {4,6,7}.
I find this technique quite useful in solving difficult killer puzzles, although it could only be applied after a cage is narrowed down to a few candidates.
Hope other users will find it useful too! And if djape likes it you can describe this in details in your solving techniques column…
I gotta tell ya, there’s nothing quite like your killers. I do those almost exclusively now. I agree about the killer book for Christmas. I promise to be good the rest of the year!! lmao
Thanks for the great site. Definately my most used “Favorites” webpage.
I have many solutions to Brain November 1st.
1st row: 8,9 or 9,8
5th row: 3,8 or 8,3
8th row: 9,3 or 3,9
3rd column: 1,2 or 2,1
6th column: 2,5 or 5,2
8th column: 5,1 or 1,5
Atapuerca, did you take into consideration that the November 1st Brain was actually “Brain X”, meaning a diagonal puzzle which must have all of the digits 1-9 on BOTH diagonals, which are marked in the puzzle by grey lines that look like an “X”?
There are precisely 4 diagonal&non-diagonal solutions to this puzzle. There is precisely ONE solution when you know that it’s an “X”. Please bear that in mind!
I wrote a post knowing that new visitors could be consfused by the “X” variation that I (exclusively?) create. It can be found here:
http://www.djapedjape.com/?p=89
Cheers!
WOW! Are these puzzles getting harder and harder or is my brain slowing down. Really struggled with some from last week. Keep up the good work!
either im getting smarter or todays killer was by far the easiest yet! did it in under 15 mins. Makes a nice change!
¡¡¡FANTASTIC SITE!!! I love the killer sudokus. What about the sundays? My brain doesn´t rest.
Congratulations from Spain. I´m waiting your killer sudoku book.
P.D. Please, More insane killers. The puzzles are getting easier each day.
Thank you, djape. I didn’t know about that X variation.
Congratulations for you site!
Thought you’d beaten me today, but finally worked it out. A book for Christmas would be good, though my husband might not agree!!
Hello djape,
nearly every day I look for your new puzzle and I’m a real fan of your site.
I found the method again to fill your puzzle in your Perfect Sudoku Program (txt-file), but I can’t find a way to use the program in an appropriate manner. Haven’t you seen my post in the contact category from Nov 4th and my questions how to get only the legal values (and not all values)?
Would by glad to hear from you!
Zauspon, I finally realized what you’re asking.
Basically, if your puzzle has no solutions, you will always get all values 1-9 when you select “show values”. So there must be something wrong with the puzzle you’re creating. Check with the “killer.txt” file that can be downloaded from this page and you’ll see that it does show only some legal values depending on which solving technique you choose.
Regarding the “elimination switch” – it’s checked and disabled, meaning that elimination is always on. This means that if one cell is solved, than that number won’t appear in the list of legal values in that row, column and nonet.
Obviously, you can’t get a hint if the puzzle has no solutions.
I hope it’s now clear enough.
Cheers!
What is the order of the ratings from highest to lowest?
ASTjitters, the order is exactly as it’s shown in the poll (upper left corner of the site).
Thank djape,
now it works wonderful!
My first attempt to design a puzzle wasn’t very coordinated and so I managed to receive an invalid value „:0:„ in the txt-file.
That have to be the origin of all my problems but now I am cured.
Try looking in the top left hand corner of this page.
Just trying out this to solve a puzzle I got stuck on – believing it unsolveable. Your software gave me the whole (unique) answer but I still have no clue how it is solveable.
Is it possible to solve a puzzle step by step? If so how?
Also having input the puzzle and switched to ‘sole’ mode and switching on innies/outies I dont see any showing – even though there are at least two.
btw the ‘on-line help’ just directs back to your web page.
Hope you see the above as constructive – I very much enjoy your site.
Thanks
Brian
Brian,
To see how which cells are solved and which possible values are removed using different solving methods, you must first select “legal values” and then the solving methods you want to use. This answers your 2nd question and in part 1st. By selecting different methods you see how far you get, so it’s “sort of” step-by-step.
At the moment, I have so many things which are all related to GENERATING different sorts of puzzles that I do not have time to focus on my software. That is why I made it free. It’s the only software that solves Killer Sudokus and that should be it’s primary use. For the time being I do not intend to enhance other features, but I will surely do that at some later stage. There are so many other programs that do that, anyway.
Terrific killer today. Took me almost an hour. Nice change after the easy and cool killers you’ve published this week.
I was away on holidays and missed the Insane puzzle from the 28th October. I can’t find it anywhere on the site. Anybody help?
Judging by the poll, the most popular killer is the insane. As you don’t post any killers over the weekend, why not post an insane every Friday so us “killerholics” can have the whole weekend to solve it?
(PS. An IQ every Thursday would also be nice)
Hey, thanks a lot for the Insane today! Can’t wait to solve it!
Hi, The yesterday IQ sudoku is great. I took hours to solve it. I have done it just a few minutes ago. Thanks
Hi, the IQ puzzle from 20051110 was a good challenge. I enjoyed it and it brought me from a bad to a good mood.
However, I solved the todays insane in just minutes. why!!
Was that a real INSANE today or am I getting better? – I found it far easier than recent BRAINS. More tough ones please.
congrats for this page ¡¡¡ i love it ¡¡
Eamon i have this insane from 28 october, if you give me your email, i send you, best regards
I agree with Agueda,yesterdays I.Q. much harder.perhaps because its Friday.Yahoooooo!
Why?
Hello eamonn
here is the insane from 20051028:
*–**–**–**–**——**——**–*
|16||6 ||12||17||10 ~ ||9 ~ ||14|
| || || || |*——**——*| |
| || || || |*——**——-* |
|~ ||~ ||~ ||~ ||16 ~ ||~ ~ ~ |
*–**–*| || |*—* |*———-*
*——*| || |*–*| |*——**–*
|11 ~ ||~ ||~ ||36||~ ||15 ~ ||22|
*——**–**–*| |*–**——*| |
*–**–**——*| *—**–**—* *
|11||16||21 ~ ||~ ~ ||26||~ ~ |
* || || || *—*| |*——*
* || || || |*—* |*–**–*
|~ ||~ ||~ ~ ||~ ||~ ~ ||9 ||4 |
*–**–*| *—*| || || || |
*——*| |*—* || || || |
|7 ~ ||~ ||~ ~ ||~ ~ ||~ ||~ |
| *—**–**—* |*——**–**–*
| |*——**–*| |*–**–**——*
|~ ||13 ~ ||13||~ ||15||18||8 ~ |
*–**——*| |*–*| || |*——*
*———-*| *—*| || |*–**–*
|20 ~ ~ ||~ ~ ||~ ||~ ||5 ||14|
| *——-**——*| || || || |
| |*——**——*| || || || |
|~ ||11 ~ ||10 ~ ||~ ||~ ||~ ||~ |
*–**——**——**–**–**–**–*
SORRY,this doesn’t look very well! Perhaps you can copy it and report it in a non-proportional type like “Courier”.
Alright everyone, if you’re claiming today’s insane was easy, please let me know how you solved it (the first few steps explained in your words). I’d like to see if I’m missing something in my rating system so I could improve it.
If I get a few good explanations for this I will reward you with another insane, out of schedule, posted on Sunday.
Thanks in advance everyone! 🙂
Enjoy your weekend!
It took me 30 mins to get a number on the insane (started top left), but after that, it was plain sailing. It must be the way I solve them coz despite what other people say,Thursday’s IQ was much easier.
Mike Japan
I want a Sunday killer so;
Top left nonet innie = 17
Top left nonet 22 = 985 or 976
R3C2/3 can’t be 98/97/96/ also can’t be 85/76 coz of R2 13. Must be 95 so R3C4 = 8
Mike Japan
yes, today was very easy, i started with the third nonets.. and the rest was very logic
I cannot get the print button to work. Any advice?
Love the puzzles. This page is my first hit each morning.
I found today’s Insane easier than yesterday’s IQ.
I started with the top right box. The 2 squares outside the box had to add up to 7.
The “4” had to be 1/3 or 3/1. It couldn’t be 3/1 as a 4 cannot go in a 2 square “8”.
So the “4” was 1/3 and the “8” was 6/2.
This meant that the “7” had to be either 1/6 or 6/1.
As stated by Mike the two squares on the far right have to be 8/9 or 9/8.
The top right box is now:
2-8/9-8/9
3-4/5-4/5/7
1/6-1/6-4/5/7
I too would like an extra puzzle on Sunday 🙂
Chris
The IQ killer on 11/10/05 was a masterpiece.
thanks again for a great site!
when can I order your book of killers?
Just catching up on the Killers for this week and thought I’d jump in the deep end and do the Insane first!
Initial moves:
r1,c8&9 must sum to 17 therefore 8,9 candidates.
4-cage (r2,c6&7) has to be (1,3) or (3,1)
Box 3 innies sum to 5 – either 1,4 or 2,3. r1,c7 can’t be 4 because it’s an 8-cage, therefore r1,c7 must be 2 and r1,c6 is 6, therefore r2,c7 is 3 and r2c6 is 1.
7-cage in box 3 must be 1,6 candidates.
r2,c8 (4,5); r2c9 (4,5,7); r3c9 (4,5,7)
22-cage in row 3 is 5+8+9 or 6+7+9 – must contain 9.
10-cage (r1,c1&2) must be 3,7 candidates, leaving r1,c3 as only place for 1 in row 1.
r1,c4&5 must be 4,5 candidates.
9 cage in row 2 must be 2,7 candidates -> remove 7 as candidate from r2c9 -> 7 entered in r3c9.
Enter remaining candidates for box 2. 14-cage must use 9+2+3 -> 8 entered in r3c4.
22-cage in row 3 – remaining candidates must be 5,9 -> 4 entered r3c1.
Thus top 3 rows:
(37)(37) 1 (45)(45) 6 2 (89)(89)
(68) (68) 2 7 9 1 3 (45)(45)
4 (59)(59) 8 (23)(23)(16)(16) 7
It’s taken me far longer to type all this out than to do it – approx 5 minutes to that stage!!
Now – can we have a Sunday bonus, please?!!
I’m confused 🙂
All explanations here are sound. Cathy’s explanation is exactly the way I intended the puzzle to be solved. Mike’s explanation is beyond insane if I may say – it’s more difficult that way. 🙂
But still, this doesn’t help me. I thought these initial moves were very hard to find. But what is it that you found so difficult about the IQ puzzle posted yesterday then? What makes it more difficult than today’s?
To me, the only difference between those two puzzles is that IQ has 6 cells that can be solved by simple innies/outies. It also requires cage splitting which I now see you don’t have any problems using.
So I still don’t get it 🙁
In a killer sudoku, can two cells in the same cage have the the same value?
example r3c3,r4c3,r4c4
If the sum is 17, is (4,9,4) a possibility?
Eric, the answer to your question is NO.
At least this is true for the puzzles that I post on this site. There’s been some discussion about that on other sites as well as here and the general consensus is that, even that it is possible, it shouldn’t be allowed. It makes Killer Sudokus more in line with classic Sudokus.