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storm_norm
Joined: 18 Oct 2007 Posts: 1741
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Posted: Fri Jan 15, 2010 7:24 am Post subject: daily VH walk-throughs, tutorial vids and more |
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since sudoku is very enjoyable to me, I thought I would share the experience of how I solve the puzzles on the Daily sudoku site.
when you click on the link below you will be taken to a channel where you can watch videos on how I attack the puzzles using the Draw/Play tool.
Basically, the video is a screen shot of my desktop where I will either use the Draw/Play tool or Sudoku Susser and me talking myself through the solution. that is all. no fancy music, no fancy graphics and no professional commentator. sorry.
I am not doing this as a promotional thing, its not meant to be an advertisement for anyone or anything. its just my way of posting a purely educational and recreational tool on how I approach puzzles and solve them.
please enjoy.
the library of videos will start to fill up as I post more videos. you can check the list of "recent videos" and click on the video you want to watch, or you can sit back and watch the continous loop of videos as they play 24/7.... yeah I know, boring !!!
here is the link
http://www.livestream.com/storm_normsudoku
and storm_normsudoku does have an underscore between storm and norm.
if you have any questions or comments please let me know.
if you have a puzzle that you want walked through please post them here in the forum and I will get it on video ASAP.
here is a sample screen shot of how the video looks when I am using the draw/play tool. again, nothing fancy.
when I transition to solving harder puzzles, like Danny's or the diabolicals and Freeps then I will use Sudoku Susser as my background program.
Last edited by storm_norm on Fri Jan 22, 2010 2:33 am; edited 1 time in total |
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wapati
Joined: 10 Jun 2008 Posts: 472 Location: Brampton, Ontario, Canada.
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Posted: Sun Jan 17, 2010 4:45 am Post subject: |
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It is too blurry for me.
I am at 1024 pixels by something, my netbook is smaller.
Why isn't your video the main item on your sending?
I need adds? |
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storm_norm
Joined: 18 Oct 2007 Posts: 1741
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Posted: Sun Jan 17, 2010 5:57 am Post subject: |
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wapati,
not sure how the video would look on the netbook. I will try and change the resolution in the next video I record.
I will probably make some trial and error adjustments as I post videos. |
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wapati
Joined: 10 Jun 2008 Posts: 472 Location: Brampton, Ontario, Canada.
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Posted: Sun Jan 17, 2010 6:19 am Post subject: |
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Don't worry too much about me.
Your sample pic is about the quality I get, useless to my old eyes. |
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storm_norm
Joined: 18 Oct 2007 Posts: 1741
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Posted: Mon Jan 18, 2010 2:19 am Post subject: |
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I have uploaded a video where I zoom in on the graphics. I believe that zooming in might solve some blurriness problems. but its not going to solve the blurriness when I macro-out and show some chains, etc. |
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storm_norm
Joined: 18 Oct 2007 Posts: 1741
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Posted: Tue Jan 19, 2010 3:15 pm Post subject: |
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uploaded several tutorial vids on various techniques. more to come. |
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storm_norm
Joined: 18 Oct 2007 Posts: 1741
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storm_norm
Joined: 18 Oct 2007 Posts: 1741
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keith
Joined: 19 Sep 2005 Posts: 3355 Location: near Detroit, Michigan, USA
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Posted: Sat Jan 30, 2010 7:29 am Post subject: |
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The original explanation of an M-wing is here:
http://www.dailysudoku.com/sudoku/forums/viewtopic.php?t=2143
Norm,
I found your explanation in the video somewhat dense, perhaps because of your use of general notation. Can I suggest the following line?
Code: | *--------------------------------------------------*
| 34 7 9 | 16 8 36 | 5 24 124 |
| 8 1 2 | 4 7 5 | 3 6 9 |
| 34 6 5 | 19 2 39 | 147 8 147 |
|----------------+----------------+----------------|
| 9 8 6 | 5 3 1 | 47 24 247 |
| 7 5 4 | 29 6 29 | 8 1 3 |
| 1 2 3 | 8 4 7 | 9 5 6 |
|----------------+----------------+----------------|
| 25 4 7 | 26 9 8 | 16 3 15 |
| 6 9 1 | 3 5 4 | 2 7 8 |
| 25 3 8 | 7 1 26 | 46 9 45 |
*--------------------------------------------------* |
You start a search for an M-wing by looking for two cells that have the same two candidates (and are not in the same row, column, or box). For example, the two cells 16 in the grid above.
Now, can you find some logic to connect these cells? If you can, there are two possibilities: They are a remote (or conjugate) pair (discussed elsewhere), or they are a complementary pair: They have the same value.
In this grid, we have 26 in R7C4. We can say the cells 16 have the same value: Either both are 1, or both are 6. We have used strong links on 6 to establish this.
Now, look for a strong link on the other candidate (in this case, 1) at either end. This is embarrassing! There are four possibilities. Lets take one of them.
16 in R7C7 has a strong link on 1 with R7C9. So, we have an M-wing:
R1C4 is 1, or:
R1C4 is 6, R7C7 is 6, R7C9 is 1.
R1C4 and R7C9 are pincers on 1, eliminating 1 in R1C9.
I leave it to you to find the other three M-wings. They all make eliminations.
You can write this as: Code: |
a b c d
16 = 26 = 16 = 15 |
a and d are the pincer cells.
There are some general observations.
1. So long as there is a strong link on 1 between c and d, it does not matter what the candidates in d are.
where x is any number of candidates, is still an M-wing. (Credit: keith)
2. So long as there is a strong link on 6 between b and c, c can contain other candidates in addition to 1.
has been called a generalized M-wing, a gM-wing. (Credit: Nataraj)
3. The link on 6 between a and b can be weak. (6 in a implies not 6 in b. Not 6 in b does not imply 6 in a.)
is a half M-wing: The strong link on 1 can only be added at one end. (Credit: ravel)
4. In a half M-wing, if the pincers a and d are in the same house (row, column, box), there is a cycle, and a and c are pincers on 6. (Credit: re'born) [Do I have this last one right?]
Keith |
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storm_norm
Joined: 18 Oct 2007 Posts: 1741
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Posted: Sun Jan 31, 2010 7:06 am Post subject: |
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Keith,
I think the confusion in explaining M-wings lies in fact that the chain may or may not contain two identical bi-value cells like a w-wing does.
in your example cells a b c d, cell c isn't restricted to being bi-value. but cell c must contain the same two candidates as the starting bi-value cell. and they must be weakly linked, so that the pincer candidate can be strongly linked on the end.
i don't know how to explain it better than that.
in actuality the chain starts out much like a W-wing.
Bi-value cell {XY}
does X or Y "see" (a.k.a. weakly linked) a strong link on X or Y.
if on y then...
we stop at the other end of the strong link to check if that end also contains candidate X. (we don't care about this in a w-wing because this end of the strong link would see an identical bi-value to the one we started).
graphic representation...
Code: | W-wing:
weak link in row/col/box
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(X=Y) - - - - - Y
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||<----- strong link in a row/col/box
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(X=Y) - - - Y
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weak link in a row/col/box
M-wing just slightly different:
weak link in a row/col/box
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(X=Y)- - - - - Y
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||<---------- strong link in a row/col/box
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X = = = (X-Y)<-------weak link in cell
^
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strong link in a row/col/box |
in the diagrams, imagine going around clockwise and start with the bi-value XY cells, make that cell a
I realize that it looks like the weakly linked XY cell has only two candidates, but it doesn't have to contain only two candidates.
I know the graphics aren't the best but hopefully its pretty evident that the M-wing and the W-wing differ in where the second weak link must happen. it must happen in the c cell.
Last edited by storm_norm on Sun Jan 31, 2010 8:27 am; edited 2 times in total |
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storm_norm
Joined: 18 Oct 2007 Posts: 1741
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Posted: Sun Jan 31, 2010 7:48 am Post subject: |
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the half M-wing is a loop.
Code: | m-wing loop, some people call it a m-ring
imagine the left up and down line is a row/col/box.
see how the X candidates end in the same house? this causes the loop.
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(X=Y) - - - - - - - Y
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X = = = = = = =(X-Y)<------weak link in a cell
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^
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row/col/box |
very powerful situation.
it sometimes shows up in harder than hard puzzles.
this beauty can sometimes show up as a first move in puzzles greater than 8.3 SE and crack similar puzzles. |
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storm_norm
Joined: 18 Oct 2007 Posts: 1741
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Posted: Fri Feb 19, 2010 7:56 pm Post subject: |
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sorry for the delay on posting new vids.
I was having a problem with the software connecting to the server and was finally able to fix it.
got some vids up...
2-18-10-VH
2-16-10-VH |
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Mogulmeister
Joined: 03 May 2007 Posts: 1151
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Posted: Wed Apr 14, 2010 8:28 pm Post subject: |
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Norm,
Are you able to measure how many hits you're getting on these. They're good because they're quite conversational...a bit like Bob Ross for Sudokuists! |
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storm_norm
Joined: 18 Oct 2007 Posts: 1741
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Posted: Thu Apr 15, 2010 4:21 am Post subject: |
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its not given as a number of hits.
instead its shows up as accumulated viewer minutes.
the last few months have been busy so I haven't been able to dedicate the kind of time I would like with this project. late last year I had lots of time which gave my mind time to visualize a project like this. |
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