Samurai Sudoku rules
I’ve been asked a few times to post some Samurai sudoku solving tips. Well - there aren’t any special tips that apply exclusively to Samurai. Standard Sudoku rules apply, but to make things clear for newcomers, I’d like to give a brief set of instructions.
Rules:
1. Each Samurai Sudoku puzzle consists of 5 overlapping “classic” 9×9 Sudoku sub-puzzles.
2. Each 9×9 sub-puzzle must be solved according to the rules of Sudoku: each row, column and 3×3 box must contain all digits from 1 to 9 – therefore, digits cannot be repeated.
3. Each Samurai Sudoku puzzle has one solution only.
Warnings:
1. DO NOT ATTEMPT to completely solve each sub-puzzle as an individual puzzle!
2. Each 9×9 sub-puzzle when solved individually could have more than one solution.
3. Never resort to guessing – our puzzles can be solved using deduction logic.
Solving suggestions:
1. Work on the puzzle as a whole.
2. Start with one sub-puzzle and solve as many cells as you can, until you can’t go further (do not guess!)
3. Move on to the next sub-puzzle. Use clues from the previous sub-puzzle.
4. Repeat step 2 for that sub-puzzle.
5. Keep repeating steps 2-3-4 until you solve the whole puzzle!
6. Do not start with the center sub-puzzle. They usually have fewer clues than other sub-puzzles.
Usual classic Sudoku techniques are required to solve these puzzles: naked and hidden singles, naked and hidden subsets (pairs, triplets etc) and “row/column and box interactions”. For the hardest of puzzles X-Wing and Swordfish techniques might be needed.
Killer Sudoku fans
February 13th, 2006 at 11:18 pm
For newcomers — what are naked and hidden singles, naked and hidden subsets, etc, as mentioned above? Or where can I find out where they are — your help only tells you how to solve sudoku x puzzles, not regular ones (or samarai).
February 28th, 2006 at 5:36 pm
Now, I´m looking for link to your discus forum.
March 6th, 2006 at 3:42 pm
[…] 1. For Samurai puzzles, read this article: http://www.djape.net/sudoku/wp/?p=144 2. For other puzzles, make sure the puzzle is not an “X” (diagonal) 3. For puzzles from The Washington Post and The Express, read this: http://www.djape.net/sudoku/forum/viewtopic.php?t=87 (and also read the article from point 1). […]
April 17th, 2006 at 5:15 am
I’m gonna work out this Sunday’s solution. I love a logical challenge on paper.
April 18th, 2006 at 5:45 pm
I have been looking for about an hour now and can not find the solution to the 4-14-2006 Express Lookout Weekend Samurai Sudoku puzzle. My friend has 3 of the 5 puzzles done and has an error. I was going to help her find it. Can you tell me where the solution is located. Thanks!
April 19th, 2006 at 1:37 am
Terry, I’m sorry but we only post solutions for the puzzles printed in The Post. We don’t post those from The Express. That’s the deal we made.
May 2nd, 2006 at 8:47 pm
Dear DJape,
I lost my solution to the online samuri game from April 25. Is it possible for me to get the solution again?
Thank you,
Cristina
May 4th, 2006 at 1:54 am
My brother Mom and i have just started these puzzles and are going crazy to try and finish them. they are so addicting and fun!!!!!!!!
August 24th, 2006 at 12:34 pm
I would like to get a blank copy of the puzzle that is posted in the sunday post.
August 24th, 2006 at 1:22 pm
Hi Mary,
Sorry, we cannot show puzzles from The Washington Post on our website. You can get a blank Samurai grid here: http://www.djape.net/sudoku/wp/index.php?dl=images/samuraigrid.png
Download it, print it and copy the given numbers from the puzzle that you have.
Good luck!
:)
September 26th, 2006 at 9:22 am
Thanx 4 the rules/tips that you listed. They give more than any other site has listed of any kind.It may not be needed for everyone but in the Samuarai the clues give some more help. Thanx. Rich
December 18th, 2006 at 10:20 pm
Hello. I am solving this Sunday’s (12/17) Samurai Sudoku puzzle in The Washington Post and i was wondering, is it possible to solve it without using the X-Wing or Swordfish Techniques? (it says its a 2 out of 5). Also is whats printed the post Samurai Sudoku X or Killer? And what exactly is the difference between the the three versions?
December 20th, 2006 at 4:06 am
I would still like an answer to my first question. Also at the top you said “Well - there aren’t any special tips that apply exclusively to Samurai.” well i believe i have found one that does. Well it would work for any large puzzle that overlaps in at least one nonet. It has to do with how numbers repeat because of the overlap. I can explain in detail if you want.
January 25th, 2007 at 7:07 pm
Hi Chris,
Sorry for responding this late…
Yes, 12/17 Samurai puzzle from The Post can be solved without X-Wing and/or Swordfish.
It requires either naked/hidden subsets OR row/column and nonet interactions. There are a couple of approaches to solving it.
In fact, about one half of the puzzle can be solved using only naked/hidden singles.
To answer your other question:
- Samurai Sudoku puzzles are those that you can see in The Post every Sunday.
- Samurai X puzzles are similar but with one additional rule: each diagonal (there are 10 diagonals in each Samurai puzzle) must contain all numbers from 1-9, just as any row/column/nonet.
- Killer Samurai: those are completely different. You don’t have any given numbers, instead you have “cages” (fences) with a number which indicates the sum of the numbers within a cage. Don’t worry about Killer Samurai - if you are interested, you should first practice Killer Sudoku which you can find every day on my “Daily Killer” page: http://www.djape.net/sudoku/wp/index.php/daily-killer/
If you have any further questions it is best to ask them in the forum: http://www.djape.net/sudoku/forum
Have fun!
Djape
February 26th, 2007 at 4:39 am
Can you explain or point me to a reference to explain what are naked/hidden singles or subsets. I am a new player. Thanks
February 26th, 2007 at 10:57 am
Norbert Dee, you can find that in the classic sudoku techniques section: http://www.djape.net/sudoku/wp/?p=157
djape
July 16th, 2007 at 12:37 am
Hello,
I was out of town on June 17, 2007.
Is there any way I can get a copy of the samurai sudoku from the Washington
Post?
Thank you,
Emma Lee
July 16th, 2007 at 1:52 pm
Hi Emma Lee,
Unfortunately, the answer is no. The deal with The Washington Post is to show only solutions for the puzzles and not the puzzles themselves. This is simply because those puzzles have been designed exclusively for the readers of The Post and if I showed them on my site they would be available to anyone.
I hope you find some other puzzle on my site that you find interesting.
August 9th, 2007 at 7:07 am
I do the sudoku alot with 5 others from work. I found a Samurai sudoku and made copies for the others i do them with.. we all are still working on the same Samuri sudoku for the past two weeks and none of us have been able to figure it out yet.. There ready to kill me.. HELP.. ( this samuri sudoku is only a 2 out of 5 )
August 16th, 2007 at 8:19 pm
Hi, i’m a newcomer to this website but not to sudoku…..but i just started working on samurai sudoku puzzles…..and from what i seen so far from this website, i see there are a lot of techniques that i never knew of, when i was doing regular sudoku puzzles…i was just wondering if you had a page just explaining all the different types of techniques and their names that you can use?
August 25th, 2007 at 10:51 pm
Hi,
I am a samurai wizard and never spend more than a leasurely hour on anything under a 4 but the last 2 puzzles (August 18, and todays, August 25) have gotten me at a total stand still with nothing more to do than start guessing and they are ‘2′. I never guess. Is someone else writing these?
Thanks …
August 25th, 2007 at 11:46 pm
Hi Janet,
No, it’s still me creating these puzzles.
I don’t think the difficulty of the two puzzles you mention is any different from other puzzles.
Where did you get stuck? No guessing is required, I can assure of that. Perhaps it was just your bad day?
Good luck!
Dj.
September 15th, 2007 at 6:54 pm
I am curious to know whether a “5″ rating means it’s harder than the lower ratings. I have also found that a 4 rating appears easier than a 2 rating. Can anyone tell me which is the hardest rating?
September 16th, 2007 at 3:02 pm
Manny, yes, a higher number means that the puzzle is more difficult. However, the difficulty of a puzzle is a very personal thing, to some people some puzzles are easier than other, while some people would find the opposite.
Do not pay too much attention to the indicated difficulty. Try to solve the puzzle and enjoy doing it!
Good luck.
January 21st, 2008 at 9:27 pm
Dear Sir,
While attempting to solve the Samurai Sudoku (Wash. Post, Sunday 1/20/2008) I seemed to have arrived at non-unique solutions). Four of the 9×9 puzzles solve uniquely and are consistent amongst themselves. The fifth 9×9 puzzle (bottom right seems to have multiple solutions) with two non-unique rectangles for the digit pairs 54 & 89.
My solution for the this lower right puzzle is with x=54, y=89
192 3xx 876
853 671 429
746 y2y 135
427 583 691
368 192 547
519 467 283
634 y1y 752
285 736 914
971 2xx 368
FYI, the center puzzle solved as
861 234 579
523 789 416
479 156 238
634 527 981
952 861 347
718 943 625
386 475 192
147 692 853
295 318 746
Could you please comment on the uniqueness of this Samurai puzzle,
Thank You
Peter M. Smith
January 22nd, 2008 at 10:44 am
Dear Peter, the problem is with your solution of the center puzzle. You have two 6s in the last column of the center puzzle, which, of course, is against the rules.
January 23rd, 2008 at 3:04 am
Hey… so I was looking for something to check my one of my sub-puzzle things.. so is there anyplace I can go to check my work?
April 7th, 2008 at 9:22 pm
After trying to solve one of these since january, I was finally able to solve the 3/30/08 edition in the wash Post. after working on it for over a week! I have a hard time understanding the written explainations on tips to solve. I am reminded of the Louis Armstrong Quote about What is jazz? “If you have to ask you’ll never know? That’s how I feel about x wing and sword fish,and naked triples. I think i need a live chat version of solving tips:) I just don’t understand the explainations.! anyway, I’m off to try my luck with the 4/7 edition!!!
April 7th, 2008 at 10:20 pm
Claudia, X-Wing and Swordfish techniques are never needed in the puzzles that are published in The Washington Post and/or Express.
Naked/hidden triplets might occasionally come about and they can be difficult to spot, but with a little practice you should be fine.
The best advice I can give - practice those advanced techniques (such as naked/hidden subsets) on regular Sudoku puzzles and then move on to the Samurai puzzles.
Good luck and let us know how you’re doing!
June 30th, 2008 at 3:05 am
How do you determine the difficulty, example 0-5? Have you ever had a 0? Is 5 the most difficult?
September 30th, 2008 at 2:05 pm
Has anyone solved the puzzle from Wash. Post 9/28/08. I am stuck on the top right boxes. What did you get?
September 30th, 2008 at 2:59 pm
Dennis, you can find the solution on the http://www.djape.net/sudoku/wp/index.php/solutions/ solutions page.