The Soduko Craze
Part of my daily routine is to try and sit down each night and read the paper I get delivered. I'm not much of a crossword person, so I normally skip the puzzles page. Then I noticed all this talk of the Sudoku "craze" that was "sweeping the nation". It's only recently that I started actually playing it and found myself literally swept away with it.
Here's what a typical puzzle looks like:

The rules are simple. Each row, column and 3*3 grid must contain the digits 1 to 9.
In the week or so I've been playing I've gone from repeated failed attempts to being able to solve the basic puzzles in ten minutes or so. I've learnt a few tricks and methods but I like to think it's the daily mental workouts that have paid off. Apparently regular use of the brain can help with memory, concentration and other things that start failing at our age.
Being a Domino developer often require the use of logic, but more often than not there's little required. Hopefully, the next time I'm three loops deep in LotusScript my brain will be back to that of an eighteen year old.
If you want to learn more about Sudoku there's a Wikipedia page, Sudoku.com and even a Sudoku blog.
Apparently there are 6,670,903,752,021,072,936,960 possible games. I can't even say that number!
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{Link}
Have fun :-)
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Like you I am well hooked on the damn things. If you are after other logic puzzles then can I suggest www.kaser.com for a wide range of different puzzles. Descartes Enigma is certainly one that I have been playing for about 4 years.
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Very interesting. I think the addictive quality is how it snowballs once you get a few rows/columns/grids all set.
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There goes the rest of my productivity for the day.
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Wonder if it is valuable to start by practicing with a 4x4 matrix and digits 1-4?
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We've got these in the Australian papers now too. Pretty addictive indeed! The one above is a very basic one, took be about 8 minutes to do. Having a computer program makes it a bit more manageable once you start having to make marks as to what the possibilities of a square are.
Back to work now.. ;)
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My girlfriend is Japanese. She is pregnant and not feeling very well much of the time, so I thought that this puzzle would be a nice distraction.
Well... she solved it in about 1 minute. She didn't hesitate once and every digit was in the right spot the first time. Therefor there must be a system although she denies it of course :-) She just said that there are different grades of Soduko and this was an easy one...
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Henk. Here's yesterday's expert level Sudoku from the paper: {Link}.
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Thank you very much Jake!
This one was a much bigger challenge, she even had to take some notes. It took her about 15 minutes to solve. The basic one took me 10 minutes or so, I better save the expert one until after work ;-)
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I've not even got as far as Intermediate yet Henk. Never mind expert!
The thing I can't work out is if you should have to guess any numbers at any point or whether you should always be able to deduce each number.
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Well, she told me that sometimes you have to guess with the really difficult ones. She could deduce everything with the one you linked to above though. A few times I thought there were several options to place a digit in a grid, but she looked more ahead than I did and solved it by reasoning. I choose to think that it's just a matter of experience, otherwise I'm just dumb :-)
Thanks again for the link, fascinating stuff!
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Yup, 17 mins for that expert one, Jake. Change papers - the Daily Telegraph do a level above expert. They call it diabolical. It takes days and requires lots of holding logic in the grey matter: this can't be 2 or 4 so that must be 2 or 4 so it can't be 5 so that must be 5, sort of logic. Horrific!
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Caroline. On the weekends The Indy does one called Godoku {Link} which is the same but in hex. The mind boggles.
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@ Henk - One Minute?! I was so very proud of my 14 minute score, too. Havn't tried the expert one yet... waiting till later today. Godoku looks like more fun. But the logic involved is the same always - you just have more to remember when persuing a path of reasoning... and adding hex doesn't mean you need to be able to undestand hex, so fear not. It's still the same logic. :-) I'm actually more interested in writing my own javascript puzzle maker and solver. THAT would be a fun challenge.
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@Henk - I don't think there's a system, but I do think it requires a certain kind of brain to be able to finish one quickly - the same kind of brain that can solve a Rubik's Cube or one of those plastic sliding number puzzles in a minute or two. People like that just see patterns where the rest of us don't. It doesn't mean we're dumb. I've only just started the first one Jake posted - this hasn't caught on in the States that I know of, so I'll have to find them online if I want them, but I do believe that, as Jake says, it can become an exercise. And any exercise that is performed regularly becomes easier. So eventually I should be able to solve one. Eventually.
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I have been doing Suduko puzzles now for just a few months now, and am still quite enthralled by them; l do not seem to tire of doing them.
Can anybody tell me what differenties an Easy or Hard or even a Difficult Puzzle?
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As far as I can tell (but I'm no expert) the difficult Sudokus can have more than one valid answer. They seem to have similar chartacteristics to combinational logic with 'race hazards'. I have a theory that all Sudokus can be solved using 'product and sum' (ie AND and OR) Boolean logic equations - but I wouldn't fancy trying it! My JavaScript solver at www.tingletron.com steps through the same logical processes that you might use yourself. It's not particularly elegant code-wise, but I haven't found a valid 9x9 Sudoku that it won't solve... Perhaps you'd like to prove me wrong!!! And yes, some people can do this sort of logic in their heads. Scary!
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Solving simple Soduko is:
- 9 query's
- short and simple VB-script
- 30 seconds.
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Here's a Soduko page worth looking at:
{Link}
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Our newish javascript solver program has been available at
{Link} for a few weeks now.
Features include optional hints, both vague ones (box to look at only)
and ordinary ones (both box and number),
as well as single step and all at once solving capability.
Possibilities or pencilmarks for each empty square can be shown or hidden.
We also have a daily rated puzzle in the range mild, moderate, hard, or wicked,
and an archive of past puzzles.
We are developing small, medium, and large grids that look better
for small 800x600, medium 1024x768, and large 1152x864+ screen resolutions.
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Hi,
On the same lines, I got hooked and have now developed a site:
{Link}
Sudoku-san is an online Assistant; it gives 'intelligent' advice if asked and tries to show how you need to think to solve them. We also generate four puzzles every day and you can print the puzzles out (if you think better when scribbling).
It's a fairly new site, so all feedback very much appreciated.
cheers,
Alastair
www.sudokusan.com
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Until recently I used to buy my daily newsletter to keep up with what was happening in the world; now I go straight for the three puzzles...... and that keeps me occupied for most of the rest of the day
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Hi
they are great fun and I found it really adictive.It keeps me busy for the rest of the day after i`ve bought my paper !
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I'm only really new at these...but I think I am hooked!!
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My Dad introduced me to this in the Newspaper today and I'm hooked already!
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i just seen this on this website i downloaded it to work on. 1 for my girlfriend and 1 for myself she finished it in under 5 mins i finished it in 20 mins which i thought was very good considering this is the first one i have seen and attempted at doing...
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really cool puzzles im only 10 and i can do them
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i love crosswords, especially sodukos. if any one else likes sodukos well done!
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Hey I think SuDuko is a really fun puzzle. Even though I am 15 I think that this game is very addictive.
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easy peasy
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I am literally amazed by how this game has taken off. I heard someone say that in the old days you were considered a nerd and not cool if you played logic type games with numbers.But these days its cool to be good with logic. .......
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I am using this site for quite a while, they send a new sudoku to your mail every day.
Peace
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if anyone wants hints, newspapers, site, the above link has them all :P enjoy!
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i love doing these puzzles and im only 13. i have filled many books od the puzzles!
elainex
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What website "above"? Anyway check out {Link} for a directory of sites to Sudoku.
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My javascript based so-duko solver, show workings as it runs, and allows you to pause and print at anytime.
{Link}
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i started to get adicted to these a few weeks ago when i was ill one day and the first one i did was just impossible but i didnt want to let it beat me!!
i tryed for about 2 days and i just gave up!!!! but the next one i did took me 4 mins i was proud!!! lol
nikki b xxx
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Here is a gr8 link for all sudoku lovers <a href="http://www.sudoku.name">sudoku</a>
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Greetings,
I'm a radio producer for a new public radio show, Open Source. I'm producing a show on the love of numbers:www.radioopensource.org. If you love numbers or know someone who does please email me and/or post on our site. We would love to hear from you--especially if you call in to the live broadcast.
Many thanks, Chelsea Merz chelsea@radioopensource.org
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check out {Link}
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I also heard all the talk about this new craze 'sudoku' - so while on holiday I bought a sudoku puzzle book. Within hours I was hooked, all you need for these puzzles is a pencil and an eraser and a little bit of brain power.
I can't believe how relaxing they are to do - I usually stuggle with crosswords, find crisscross or wordsearch no challenge but with sudoku I know I might struggle but I can do them.
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I am so glad to know that I am not the only one whose is addicted to these damn things. I love it. Each time I play I figure out a new way to fill everthing in. I love it!
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i like this verry mutch
i like to know other games like this
i can sole it within 10-15 min
thanku
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what do we actually do dude =\
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i am only 13 but these sudokus have really grabbed me. i kind of have a real interest in these kind of games cos i play chess alot.
only thing about sudokus is they're so easy!! does anyone know where you can get harder ones??
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wonderful game for your brain
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I'm hooked, too!
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yeah we are all hucked
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Sodukos are plain fun! I made a webpage where you can solve new sodukos online - or you can use it to get the solution for a soduko that's causing you trouble. All online and for free!
Check it out:
{Link}
Cheers, Frederik.
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Omg I cannot stop playing them. Every time I see a newspaper I flick straight to the puzzles page to see if anyone's done the sudoku or not! They are so addictive.
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very easy and nice .it was the best. i liked it.i do it every day. i want more.
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cool
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this website is ok
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Weighing in a bit late, having just stumbled upon this page: if you're looking for free sudoku, THE place to go online would have to be the massive archive at www.menneske.no . They're classified by difficulty level. As far as I can tell, "super easy" sudoku (like the one at the top of this page) can be solved by forced moves alone, "very easy" ones add pinned squares, "easy" ones add intersections, "medium" ones force you to understand locked sets, and "hard" ones make you consider hidden sets as well. Once you get up to "very hard," unless you plan to go by trial-and-error, you need to be able to recognize patterns like forcing chains, unique rectangles, X-wings, XY-wings, XYZ-wings, remote naked pairs, swordfish, jellyfish, and the infamous squirmbag. And for "super hard," better brush up on the Nishio and Bowman Bingo techniques.
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23E2R3Q3T3
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yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis!
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For all Sudoku fan I have created a solver available on internet!
Try {Link}
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Give this sudoku site a try: {Link}">Link}
Fiendish Sudoku has new puzzles every day at five difficulty levels, and it can provide hints and step-by-step solutions.
The grid can be displayed at three different sizes (including a large size that's great for those of you with high-res displays).
There is an archive containing hundreds of puzzles. Other features include Undo/Redo, pencilmarks, and several printing options.
{Link}">Link}
- RobertN
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The links in my post above are not working... hopefully these will work:
[url]{Link}[/url]">Link}
{Link}
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al-salam-aleikm...Sudoko is a puzzle that needs intelegence..its a great puzzle that is very addictive..you dont realy need to be that good at mathematics..its just a puzzle that everyone would enjoy, and try it again and again...and when you start one you cant stop, and the time passes without even thinking about the time. Encourage young kids to try it too...
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HI PPL CHING CHONG SAYS HI PPL
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hi ppl im stuk on dis cheerz
help es
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A very interesting blog. Keep it up!
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I am a doctor who specialises in people who cannot stop playing and thinking sodoku, and it is affecting their lives.
Contact me and I will give you an appointment every day between 2 and 4.
HA...........HA
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that pezzle you gave us was ez. i solved t in like 5 minutes. i mean i'm just looking for soduko puzzle yesterday and today and that by far was the easiest. i could solve it on my computer
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So what is the solution to this puzzle?
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Yip, i am a total fan. It is totally addictive and we are having Soduko gatherings every day to solve it!
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Hi,
In www.sudoku.org.es you can find a sudoku solver made with Java. There is a sudoku killer solver even. Both work fine if you do not make mistakes, otherwise ...
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I enjoy Suduko, and decided to program my own solver in Java. It is kinda primitive, you must edit the initialization of the grid for each run. It does, however, solve any solvable Sudoku in about 3 seconds.
If you are interested in a pretty simple recursive Java program, just e-mail me
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Your page sucks why does it not have any real sudoku on it, this page is lame.......
u suck ass!
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I too discovered Sudoku by finding it in our San Jose Mercury News some three months ago. Immediately I was hooked. They get easier every day but I have achieved only one "Expert" level puzzle so far. Yes, the one above is really the easiest and I did it in about 2 minutes. I really hope it does improve the memory etc. - that's my excuse for doing the puzzles. Warning though, you can pass a tremendous amount of time. A few weeks ago, while waiting for a connecting flight back from working with the Red Cross in New Orleans, I missed my connecting flight because I was so engrossed!
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Soduko is truly addicting! You are so right! I first came in contact with the puzzle in Indian newspapers last month. When we came back to America, it was everywhere here,too. Apparently, it was invented in America and a Japanese man took it to Japan where it became peopular. Now it's back here in the U.S.! wEIRD, HUH?
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Yes, Sodukos are so addictive, I started doing them in ink to make them last longer, but that didn't help, I still finish the 5 star ones in USA Today in less than 20 minutes.
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Just in case you find a sudoku impossible to solve, on www.sudoku.org.es you can find two sudoku solver made with Java. The first one can solve normal sudoku and the second one can solve the sudoku killer. Both work fine ... when you put the values correctly ...
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Does a Suduko grid consist of 9 squares OR 81 squares.
I am finding it more difficult to answer this question than solving the actual puzzle.
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@Norman
Several thousand squares, actually. I can't be bothered to work it out, but every square with a single digit in it could form, for eg, the bottom-left corner of an increasingly larger square (if u seen what I mean). But yes, an intriguing puzzle that nobody should waste time on. :0)
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yay! suduko puzzles
woot woot
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yay! suduko puzzles
woot woot
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my mum is crazyily addicted
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I have developed an Microsoft Excel program that provides the possibilities for each cell. The first step is to enter the puzzle in a window and the next thing to do is print out the puzzle with all of the possible numbers for each cell including the given numbers.
This provides a starting point to solve the puzzle. With difficult puzzels I usually enumerate the possibilities for each cell and I found that this saved a lot of time.
Would anybody be interested in buying such a program for a reasonable price? (Say $20).
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Great blog! Love it!
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where the HELL do u get answers for this freaking thing WTF
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where the HELL do u get answers for this freaking thing WTF
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I AM WORKING ON ONE FOR A EXTRA CREDIT> AND ITS HARD> YOU GUYS ARE CRAZY IF YOU FIGURED THIS OUT.<3 WOOSH
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hello my name is undisclosed
hehe
by
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Sudoku solver :
www.sodokusolver.co.uk
have fun cheating.
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{Link}
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Lots of comments here! I ran across your site and was hoping you could try my new puzzle service: Free Daily Sudoku ({Link} You can sign up for a daily email puzzle or a puzzle via RSS feed. Thanks!
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I hate doing word serches!!!! but i tried this and it is all I do!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
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i llllllllloooooovvvvveeeeee them
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Esta muy entretenido y ademas te reta a seguir intentado resolver otros ■los felicito!
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Who creates these puzzles, computers?! I would think that creating one for us to solve would be just as, if not more, challenging than solving one. Keep them coming!
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They are sooooo much FUN!!! I love doing them in the paper especially when i'm drinking coffee in the morning!!!!
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I really really like doing them !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
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this sight was A O-K! lol
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Soduko is worse than meth!!! If you are a busy person, you never want to try one of these dern puzzles! They just keep calling your name!
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Hi I think the games are so fun i LOVE theme
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ya suduko is deffientlly addicting, you have to have sooooo much patience for them! i love it though!
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i love soduko puzzules and i play them online everyday i am also in math challenge so i get to do things like this
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quisiera saber m■s acerca del tema de sudoku y conocer que efectos puede tener sobre el individuo cuando lo juega, adem■s si ya hay personas que han trabajado esto como estrategia de ense■anza
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hi, if you're into kakuro you should check this <a href="http://www.kakurolive.com">online kakuro</a> version
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How do I generate a puzzle??
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sdvfasdfafgah
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me likey
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hey ive onli jus found out how 2 ply sodoku i love it ! it is so adictive wow!!
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Hi
Can some one tell me if there is a colour code system for Soduko?
ie.
Is 1 always a certain colour and 2 always another colour, or is there no accepted standard as yet?
Thanks
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2nd go at this question.
Are there specific colours that have been allocated to the numbers 1 to 9?
I am looking for a way to make Soduko more relevant to people with low maths comprehension, but who may be able to think through a graphic puzzle.
Any suggestions or comments will be most welcome.
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I love your puzzles
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I love your puzzles
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its a frickin retard they are stupid i hate them
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this game is really easy and just a bit to easy and change the puzzle ive been doin the same 1 for about a hour now
bye luvs u josh luv me and u sam
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your website sucks!!!!!!
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hey people! it does take a sertain type of brain to do soduko... im 14 and i did the Intermediate level in 20 minutes (yeah man) but the thing is im realy good at maths so i think that that and just thinking you can get it very well!! good luck guys and guls
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I think this post is beat but I was wondering if any of you Sodoku fans out there know of any links to a NEW sodoku that DOES involve math. There was one in the Boston Phoenix a couple days ago and they don't give you any #'s. They just tell you what the #'s in a group of boxes equals. It was great...
anyone?
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pips! MAKE THEM HARDER!!!!! and actually that was quite boring but fun !! LOL !!!!!!!!!
heya peeps!!!
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i love this game. it is challenging and helps the mind. i look for more to come
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this is really starting to get boring guys oh my god
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I wish that this website had a saduku on it that is the only reason that I clicked on it I agree it's lame!
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Haha...this sudoko game has me at work wasting so much time. I hope my boss doesn't catch me he might kill my lunch break for the day. I sure can't get enough of puzzles.
I just found a site where I can make my own jigsaw puzzles. I know some of you guys are puzzle geeks like me and might be interested in it too... so check it out: {Link}
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Thers only one soduko on this page!:(
But I still think Sodukos are awsome!!!
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u should like make something that u can play sodukis on the computer like when u log on it would be like if u wan tto play a soduko play now (for free with out down loading)that would get lots of peoples attion if u do this for me and read this if u make it so i can play on my computer the sodukos then i will tell all my friends about this websight and there u go u will have the most popular websight and trust me my hole school are my friends i am wicked popular i will give u 3 days to do this if not i will not tell my frinds most sincerly the 12 grader!!!P.S rember 3 days or evey1 will hate this websight! and this is not a threat i am 12 years old i think i do not now who to threat i was just giveing some advise e-mail me back.
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these are so fun i mean like mr.simmond does um for homwork passes how cool is that !!!!
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whoever jim is. he is a very pwnful dinger. yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis yis
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yo it is only a puzzle
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have fun every 1 and io hope you enjoy your sudoko's =)=)=)=):p:p:p:p
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I love sodukus they are so awesome i started doing them when our sub. Mrs.Chanller gave them to us and now me and my older sister love them every where i go even to sleep i do them they are sooo cool!!!!!!!!!!!!!! know what i'm sayin'
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