OK - Ask me a Sudoku Question!

Submitted By: Gath from Sudoku.com.au

To kick things off - ask me a sudoku question that has been bugging you.

Anything! A puzzle that you haven't been able to solve, or an explanation of a technique, and I'll do my best to answer it :)

(Of course, I might get Steve to help with the really tough stuff :) ).

Cheers,

Gath

115 Comments
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   PJH  From NP    Supporting Member
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Hi! It's not a ? on the puzzle, but on my grid positioning. Today it overlaps the sentence 'choose a # & put it in the grid' that's above the numbers. Yesterday it was fine. Can I fix it? Love all the improvements & extras!!!
31/Jul/07 6:26 AM
   PJH  From NP    Supporting Member
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Me again, I know why it happens now, but I still would like to know if I can fix it. When I add the 'Possibilities', the grid grows downward over the sentence and into the numbers. I don't recall that ever happening before. Any suggestions would be appreciated. Thanks for all you do (even if you can't fix the prob.).
31/Jul/07 6:47 AM
   vdV  From Melbourne
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Ok Gath an easy question with a hard/long answer.
How do you make a Sudoku? Given the rules, not forgetting the one most forget; 'Each Sudoku puzzle has a unique solution'
31/Jul/07 2:51 PM
   Gath  From Sudoku.com.au    Supporting Member
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Hi PJH,

I've sent you a message.

03/Aug/07 11:12 AM
   Gath  From Sudoku.com.au    Supporting Member
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Hi vdV,

Now that is a tough one to explain, but here goes:

Note - there are *many* ways to generate sudokus, this is just one.

1. Start with a completely blank grid.
2. Solve the sudoku. By this I mean fill in all the squares keeping to the 3 rules of sudoku.
3. Make 2 squares blank.
4. Try all combinations of numbers to solve the sudoku. If there is 1 solution, then go to step 5. If there is more than 1 solution, go to step 6.
6. Replace the last 2 numbers that were made blank.
7. You have your generated sudoku!


Gath
03/Aug/07 11:24 AM
   Gath  From Sudoku.com.au    Supporting Member
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maybe it wasn't so tough
03/Aug/07 11:25 AM
   vdV  From Melbourne
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Gath is this a trick answer, where is step 5
03/Aug/07 5:04 PM
   Gath  From Sudoku.com.au    Supporting Member
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Hi Everyone,

Sorry vdV, step 4 should read:

4. Try all combinations of numbers to solve the sudoku. If there is 1 solution, then go to step 3. If there is more than 1 solution, go to step 6.


Gath
04/Aug/07 3:28 PM
   Mamacita 2  From PA.    Supporting Member
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Gath, How does one change the update page to no longer have the tbox and fonts and things available to them. Ithink I broe my update page and now my you tube won't show even though the infor has been pasted in and the tube located...all I have is text where I should see my picture....Can you help me here...lol
09/Aug/07 2:17 PM
   Mamacita 2  From PA.    Supporting Member
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Thanks Gath.....all is now well. I don't know If you did anything or it fixed itself once I left it alone, but its as it should be, and so is my page.
09/Aug/07 3:21 PM
Dave  From Minnesota
Gath,

The tough puzzle for May 28, 2007 appears to be one of those that require advance techniques. Anyone have a solution or stratagem to post?
11/Aug/07 1:08 AM
   Gath  From Sudoku.com.au    Supporting Member
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Hi Dave,

Now *your* question is going to take a little while to get back to. Solving a tough puzzle takes me ages!

I'll check it out & get back to you.


Gath
17/Aug/07 3:10 PM
Cindy  From Ontario
How does someone who is a math ignoramus attack this problem?
Was first time lucky (months ago!) - not a good thing. Okay, where to start?
20/Aug/07 4:35 AM
   MizTricia1  From Alabama, USA    Supporting Member
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CINDY, I am not Gath and I hope he does not mind me 'helping" with this question. I would put my thoughts on your page, but you are not a member with a page available.

Suduko is not about math, it is about logic! You do not add, subtract, multiply or divide anything. You do count to 9, but that is recognition of the numerals, not really math. Sudoku would work just as well if you use letters or symbols instead of numerals.

That said, on to your question on where to start. I would suggest you read Gath's Sole candidate and Unique cantidate explination on this forum and practice those, should work to solve most of the easy puzzles here.

Also, remember you do not have to start with 1 sometimes the puzzle works better starting from 9.

Another hint, make sure to tick the check box for Automatically remove Possibilities and un tic the box Allow incorrect Moves while learning. that way if you choose an incorrect number for a space, it gives you a warning this is not correct.

Hope some of this helps, and you regain your beginners luck!

Now turning the page back to Gath
24/Aug/07 1:45 AM
   MizTricia1  From Alabama, USA    Supporting Member
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NOW Gath, I have a question. On a suduko game on my puter that hubby bought for me, I find on their easy, they play nothing like your puzzzles. I repeatedly get a set of possibilities I cannot find a way to work with. It is so often present, I wonder should there be some way to work with it to solve.

After eliminating many possiblilties , I will find I am left with something like this:

25, 27, and 257 as posssibilities in the only 3 remaining empty cells of the row, column or square.. Can you solve from that? Is there some rule? Or is it nescessary to go to the remaining row, column or square of the cell containing the 25, say, to try to eliminate one of the numbers?
24/Aug/07 2:21 AM
rtshores  From charlotte, nc, usa
Would you know where I can find mega sudoku puzzles and if so, maybe in a large size(poor vision). Thanks!

Rosie
27/Aug/07 2:42 AM
   Gath  From Sudoku.com.au    Supporting Member
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Hi MizTrica1,

When you have possibilities like 25, 27, and 257, then you usually must rely on what is happening in the other squares to solve these three. Just looking at these 3 squares in isolation will not solve them.

rtshores, try googling 'large print sudoku'.


Gath
30/Aug/07 2:02 PM
   MizTricia1  From Alabama, USA    Supporting Member
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THANKS GATH, that is what I have been doing, but I kept finding it so many times, wanted to be sure I was not missing some secret.
03/Sep/07 1:25 AM
Hannah.Taylor10  From Hannah
hi im the best at su do ku i am a whiz at it ok say hi 2 your mum 4 me peoples. peace out
hannah
05/Sep/07 4:56 PM
Hannah.Taylor10  From Hannah
hey can anyone just say hi 2 me please
im cool im smart im popular and i was in a movie
called 3rd eye open
05/Sep/07 4:58 PM
   Gail  From Cockatoo Vic AU
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Hi Hannah
05/Sep/07 6:15 PM
Richard  From PA USA
Are there formal criteria for classifying a 3x3 sudoku puzzle (i.e. easy, medium, hard)?
16/Sep/07 12:18 AM
Kim  From Fl
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Hi A student gave me a rubik cube sudoku puzzle with the numbers 1 - 9 on each side. Have you seen these? I can solve a normal 3X3 cube so I didn't think this would be a problem but I do not know the orientation of the way the numbers point on each side. The solved cube is 1 through 9 starting with a 1 in the top left and a 9 in the bottom right---do you know the way the sides are suppose to point?
Thanks Kim
20/Sep/07 9:32 AM
   Gath  From Sudoku.com.au    Supporting Member
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Hi Everyone,

Richard - 3x3 puzzle? Do you mean there are only the numbers 1-3 used?

Kim - I've never seen a Rubik's cube like this, but I would guess that the manufacturer would arbitarily decide which way was 'up' for the cube, and align the numbers 1-9 with that in mind. (and hopefully provide a picture!)


Gath
17/Oct/07 6:56 AM
   Mamacita 2  From PA.    Supporting Member
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why do I only get the current jigsaw puzzles when I attempt to work those that have previously been done. It doesn't matter which date I use...its always the same as the current puzzle. Help!!!!
19/Oct/07 8:34 AM
Peter  From Australia
Hey there, new to this whole sudoku thing (and am admitting im addicted to it), but I just wanted to get a feel of the average time it takes to complete a sudoku...

On easy, I see people posting 2/3/4 mins, (I am getting 10 mins avg)
On medium, I see people posting 4/5/6 mins (I am getting about 14 min avg)
Dont even wanna try hard or tough but they would probably take me 1 hour! haha

Thanks again :)
21/Oct/07 1:42 AM
   MizTricia1  From Alabama, USA    Supporting Member
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PETER, I have been doing these sudoku puzzles since May and I am not fast! I do not even turn on the timer, I just enjoy doing them no matter how long it takes me. I do know I am enjoying it more as I get accustomed to the computer clicks and to some of the ways to look at the puzzles. Just keep on trying.

Would you like to look into opening a free account, so you have a page for messages? I was never on the EASY puzzle page soon enough after you posted your times (but I have read all of them) to think you might see remarks to you there.
21/Oct/07 8:29 AM
Peter  From Melbourne
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Hey hey MizTricia1 :)

Thanks for the comment. I just oppened up a account after youre advice, and looks like I will be comming to this site more often. :)
21/Oct/07 12:58 PM
joel  From bathurst
hey, can i eat a pancake
30/Oct/07 10:46 AM
Gingermick  From Queanbeyan
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Hello all. I am a newbie and am having great fun solving the Easy and Medium puzzles. BUT, for the life of me I cannot solve a Hard one. I understand , I think, the technique of "pairs' but I need some helpful hints, please, folks.
02/Nov/07 5:36 PM
Terry  From Oregon

Gath, this was in today's thread on the tough page. Didn't notice you were still inviting queries to this page, and hope this isn't too late an entry:

"PJH From NP. Hi all! Why do some cells flash red when I fill in a different one? Sometimes only one will flash and other times many will flash!! 04/Nov/07 10:26 AM"

"Terry From Oregon. NP -- I wonder that as well. Should have thought of it yesterday when Gath was fielding questions. I've assumed it meant 'That number would be wrong in this/these other box/boxes as well so if you were thinking of going there next with that number, don't!.'"

Thanks!

04/Nov/07 7:49 PM
   eaa  From Tassie
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Hi Garth, mines not a question but a request. PLEASE remove Britney Spears,from the adds. Many Thanks.
09/Nov/07 11:54 AM
pdp189  From New Bombay, India
Hi Garth,

I always get a problem. In a sudoku if the configuration is
... ab abc ... pqab .. ... ... ...

Some times, only c is taken in place of abc and sometimes it is taken as a pair.. ab ab .. (i,e, c is removed. Any criteria for this? if so kindly explain.

Thanks,
11/Nov/07 11:04 PM
Guy Sheaffer  From Wyomissing.PA
How can I get a Sudoku instruction manual ?
12/Nov/07 9:47 AM
   Broni  From Qld, Australia
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Hi Garth,
I'm a newbie and get confused over two possibiilties a square. But I have never seen anywhere that instead of clicking the possibilities check box that you can just right click on the square after the number you have selected and it will show this as a possibility. PS luv the site, will become a Supporting Member as soon as I can.
Take Care,
Broni & Bella
02/Dec/07 10:28 PM
Roxanne lee Mei Ying  From Singapore
You can have more difficult sums for children.
03/Dec/07 1:55 PM
   Wagdy Kamel  From Cairo Egypt
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Hi.GATH.
My best wishes to you and many thanks for your appreciated effort.
My question is :the 16x16 is too big than my screen .what can i do to make it in small size as the other Ones.
Thanks for your response.
09/Dec/07 3:26 AM
   Dorthea  From San Francisco
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I'm trying to update my membership. and yes I'm using the ssame e-mail address.
10/Dec/07 4:10 PM
   vdV  From Melbourne
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Wagdy, if you are using a recent version (7) of Windows Internet Explorer you can zoom the screen in and out with "Ctrl"+ and "Ctrl"- (ie the control key and the + key [or - key]). You can also use the zoom button at the bottom right of the window.
10/Dec/07 6:47 PM
jm  From ak
Gath,
UNDO is not functioning when Possibility in Grid Format is checked, the possibilities are hidden when UNDO is pressed.
16/Dec/07 6:43 AM
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