Windoku 22.09.06 (September 22, 2006)

Our daily <a href="http://www.sudocue.net/windoku.php">Windoku</a> puzzles, a.k.a. NRC Sudokus, are a real challenge, comparable to the Daily Nightmare.
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Nasenbaer
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Windoku 22.09.06 (September 22, 2006)

Post by Nasenbaer »

I recently found my way to the Windokus. They give me a real headache. About 80% are on the "started, but not yet finished" list. Just haven't found all the special Windoku knacks yet. :(

But maybe its because I do them on paper. But today I had some time on my hand and I started experimenting with the SudoCue program. And I picked the September 22, 2006 Windoku.

I filled in my (few) findings and compared the markups to my paper version. Well, I found 4 cells where I missed to eliminate some digits (all in column 9), but also had a naked triple in row 1 and the "5th window" (or what's your name for the special corners) that wasn't (yet) found by SudoCue.

Long story short, that's how far I got:

Code: Select all

.---------------------.---------------------.---------------------.
| 28     1B     359Y  | 359Y   26     35    | 4      7      268   |
| 6      5789   2579  | 1      4      257   | 3      589    259   |
| 2579   4      23579 | 235679 8      257   | 2569   569    1     |
&#58;---------------------+---------------------+---------------------&#58;
| 2579   579    2579  | 2678   3      1     | 56789  4      579   |
| 47     6B     8B    | 47B    5      9     | 1      2      3     |
| 1      3      24579 | 2478   26     2478  | 5789   589    568   |
&#58;---------------------+---------------------+---------------------&#58;
| 358    578    6     | 2458   9      23458 | 2578   1      258   |
| 358    589    1     | 258    7      6     | 2589   3589   4     |
| 479    2B     457R  | 35Y    1      358   | 568    3568   79    |
'---------------------'---------------------'---------------------'
Now I tried a hint. It gave me this:
L Stiles found a Naked Triple with Digits {3,5,9}

Additional explanation from the log:
Because these 3 cells in L Stiles only allow those 3 digits, they cannot be placed in other cells in L Stiles
SudoCue marked the cells, they are shown above like this:
Y - Yellow (R1C34, R9C4), R - Red (R9C3), B - Blue (R159C2, R5C34)

So this hint tells me to remove the 5 from R9C3, correct? But why? I don't understand this technique or its name. Or maybe it's just too late. Could please someone explain it to me?

I paused my game at this point and will try to resume it on Sunday (Saturday is now mostly Clueless-day, sorry). :wink: Nevertheless I will visit the forum regularly.

Thanks in advance,
Peter
Ruud
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Post by Ruud »

Hi Peter,

I see that my Windoku puzzles have gained in popularity, but they are hard indeed.

Here is an image from beta version 2.0 of SudoCue:

Image

A Windoku has many secrets. The position of the 4 windows implies 5 additional constraints. One of them is L-Stiles, or better: the window stiles on the Left side of the grid. The house is colored light blue in the image. Because the 2 windows are located on columns 2,3 & 4, the remaining cells in these 3 columns must also contain digits 1 through 9.

Because I have configured my solver slightly differently, it discovers the complementary hidden pair first. It also found a hidden pair in row 4.

Once you know L-Stiles, you will know what R-Stiles, T-Stiles and B-Stiles are. Now you have 8 extra houses, so there must be another group of digits 1 through 9....

Ruud
“If the human brain were so simple that we could understand it, we would be so simple that we couldn't.” - Emerson M Pugh
Nasenbaer
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Post by Nasenbaer »

:idea: Aaaaaaaahhhhhhh :!: :idea:

The big light bulb just went on. :wink: First had to look up what the word Stiles means (should have done that earlier, I know). Now the fog is clearing away. I read your post where you talked about the 5 extra constraints, and I thought you meant the 4 windows plus the "corners" (R1C159, R5C159, R9C159). Never thought my way through.

(BTW, I too found the hidden pair in row 4 after I finished the post)

So, just to be on the save side and to sum it up, the constraints for windokus:
  • 9 boxes (or Nonets), the usual suspects
    4 windows (R234C234, R234C678, R678C234, R678,C678)
    4 stiles (R159C234, R159C678, R234C159, R678C159)
    1 "corner-set" (R1C159, R5C159, R9C159)
That's it, right? No hidden trapdoor or an extra chimney for Santa (who is, according to the decorations in the supermarkets, coming down on us next week)? :wink: :lol:

Well, now I know what to do for the next 3 hours...

Thanks a lot,
Peter
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Location: Cincinnati Ohio, USA

winduko

Post by Pete »

gee i saw the windows
but i saw the 5 constraint note
i never thought the four windows werent included in the 5 constraints
does this total to 9 ?
4 windows+
4 stiles+
1 corners
-----------
9 constraints.... more than traditional sudoku

went back to the windoku page and it does say 5 "additional" constraints
gotta read real careful when the puzzlemeister speaks

now i guess ill google stiles and sudoku and see where stiles fits in

I found even the ez example to be plenty hard
guess ill try agin looking at stiles and corners


*Ruud* BTW the link to the forum on the windoku page points to assassins thread
"It gets dark at night" - Olbers
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