The New Sudoku Players' Forum

[Pseudo Kiwi]

Hello everybody,

I've been thinking of ways in which words can be incorporated into Sudoku. This particular idea has the following rules:
"Every row, column and 3x3 box must rearrange to form a nine-letter word. No two words can be the same."
NB. Repeated letters ARE allowed in any unit of the puzzle.

Here is a 4x4 Lexoku (where every row, column and 2x2 box contains a four-letter word):
GA..GN
ES..RI
--------
RM..OA
AE..GL

And here are the top three rows of a 9x9 Lexoku:
MEN..WON..TDE
IGS..EDR..AHN
RAT..GNI..NEC
(spot the 9-letter words!)

Two questions:
1. What do you think of the puzzle?
2. Does a 9x9 Lexoku actually exist? (it took me ages just to get three rows)! How could you prove this one way or the other? I'm sure you could get hold of every 9-letter word somehow, but could you create a program which could combine 27 of them (or not) to make a valid puzzle?

Thanks

PK

[Animator]

First let me note that there is already a thread about one word: http://forum.enjoysudoku.com/viewtopic.php?t=202

Second, how would it work? as in, your three-rows example shows different letters... Sudoku itself is played with only nine symbols... (for example, where is the R in row 1?)

[Pseudo Kiwi]

Animator,

This puzzle is quite different from the other example which had a 9-letter word replacing the nine digits. That's why I started a separate thread.

It is also quite different from standard Sudoku. There is nothing in the rules about the same nine letters appearing in each unit of the puzzle.
Every unit simply must contain a 9-letter word, but you can't use the same word twice.
A completed 9x9 grid therefore contains 27 different 9-letter words: one in each row, column and box.

Just like in regular Sudoku, the puzzle will appear with some cells filled in, from which you have to deduce the others. In the example above, every cell in box 2 (WONDERING) might be given except the O. You can deduce that this letter could be "O" (which would make WONDERING), "A" (WANDERING) or maybe even "I" (REWINDING). Which of these you choose will depend on some of the other given letters.

Whereas Sudoku relies on pure logic (though for some of the harder puzzles I'm not so sure!), Lexoku requires knowledge of the English language, and aspects of it such as letter frequency.

Just thought I'd try and clarify one or two things, and hope I haven't confused you even more!

Regards,

PK

[Pseudo Kiwi]

I thought I'd give you all a flavour of how my Lexoku idea works in practice by composing some puzzles and posting them here.

Unfortunately I don't have the time, patience, computer program or whatever you need to generate 9x9 puzzles of this nature. On the other hand, a 4x4 version would be far too quick and easy to solve. So I went for a 6x6 "compromise": six rows, six columns, six 2x3 boxes.

The rules for completing the puzzles are simple:
Fill the grid so that every row, every column and every 2x3 box contains all the letters of a 6-letter word. The same word is never used twice in the same puzzle.

Feel free to have a crack at any or all of the three puzzles I've made. I don't know whether I've given too many clues, or not enough, or how long they take to solve, so any feedback (including the correct solutions!) would be appreciated.

Puzzle 1:

Code: Select all

* O R  |  Z N E
* R M  |  * T *
-------+-------
N * *  |  G * *
* * P  |  * L E
-------+-------
* * E  |  N * *
R V *  |  * * E

Puzzle 2:

Code: Select all

* T *  |  I * I
K * W  |  * * D
-------+-------
O B *  |  * I *
* B *  |  D H *
-------+-------
* * *  |  * * *
* * *  |  * D *

Puzzle 3:

Code: Select all

* M *  |  * * B
S H D  |  * * *
-------+-------
P * *  |  * * *
* * *  |  O I L
-------+-------
* M *  |  * D *
* A Y  |  * A Y

Tip for puzzle 1 to get you started:
Begin at the beginning (r1c1) - what letters could possibly go there?
(I can only think of two possibilities). From there you should be able to deduce other letters.

I thought you might like something to give you a break from masochistically hard Sudoku puzzles!

Good luck,

PK

[su bloko]

Puzzle 1:

Code: Select all

* O R  |  Z N E
* R M  |  * T *
-------+-------
N * *  |  G * *
* * P  |  * L E
-------+-------
* * E  |  N * *
R V *  |  * * E

It is a little tricky PK. I think you can put F then E in the first region and I and H in an indeterminate order in the second. That gives you reform, zenith, frozen and hermit. Then it looks a little tricky. To me at least!

Those are all nice words, but it leaves a nagging doubt as to how large your vocabulary might be.

Anyway, my guess is it was probably as difficult for you to generate these puzzles as it will be for one of us to solve them!

Oh and it took me about 10 minutes to "solve" that little bit of your puzzle - assuming I am correct so far!

[scrose]

I thought you might like something to give you a break from masochistically hard Sudoku puzzles!

And this puzzle isn't masochistic?

[Pseudo Kiwi]

Hi,

I've been away all weekend so haven't been able to reply.

I apologise for making these puzzles a tad tricky. At least now I've got a better idea of how many letters to put in at the start.

Su bloko - you're spot on so far. In the 2nd box, the I goes in column 4 and the H in column 6 (putting an I in column 6 would give four vowels including three E's in that column, which would be an unlikely combination). So in column 4 you have ZING, and in column 6 you've got HEEE (think of words with an H and 3 E's).

My vocabulary isn't that big, and I've been careful only to use fairly common words. Besides, any letter in the puzzle must form part of three words, so words like "syzygy" wouldn't be easy to fit into the puzzle!

You were asking how long it took me to create the puzzles. The first one took 3 hours. Puzzle 2 was a bit quicker (an hour and a half) but puzzle 3 was around the 3-hour mark again. I do them one box at a time: getting the last box in place takes forever! Maybe "hermit" was an appropriate word to put in I'm sure I'm not the only person here who's spent that long (or longer) on really hard Sudoku puzzles.

I might post versions of 2 and 3 with more clues some time soon.

Enjoy,

PK

[Pseudo Kiwi]

Here are easier versions of all three puzzles: I didn't give enough clues last time (I know what all the words are, so it's not easy for me to know how many clues you need to make a reasonable stab at solving the puzzles - it seems like for a relatively easy version you need 50-60%).

Puzzle 1:

Code: Select all

* O R  |  Z N E
* R M  |  * T *
-------+-------
N * *  |  G E *
* * P  |  * L E
-------+-------
D * E  |  N * *
R V *  |  * S E


And you've already got some of the other letters, so this one should be really easy (!)


Puzzle 2:

Code: Select all

* T *  |  I * I
K I W  |  * * D
-------+-------
O B R  |  * I N
* B *  |  D H *
-------+-------
* * T  |  * G *
R * N  |  * D G

Puzzle 3:

Code: Select all

A M *  |  R * B
S H D  |  A E *
-------+-------
P * *  |  R * *
E * *  |  O I L
-------+-------
* M *  |  * D *
* A Y  |  * A Y

[su bloko]

PK, I think your puzzles are still too difficult! I think that they may have more than one solution which might mean you need to provide more clues! Anyway here is one solution to your first puzzle:

Puzzle 1:

Code: Select all

F O R  |  Z N E
E R M  |  I T H
-------+-------
N G A  |  G E D
I R P  |  S L E
-------+-------
D I E  |  N I D
R V E  |  I S E


Which gives:

frozen
hermit
nagged
perils
indeed
revise

friend
virago
ampere
sizing
listen
heeded

former
zenith
paring
sledge
derive
inside

My guess is that this is not your solution, because virago (a courageous woman) is not a common word.

Let us know your solution!

Regards, Richard

[scrose]

Wow! Standing ovation! Here I was impressed just when you were able to fill in the first two blocks. I stared at the rest of the puzzle for about ten minutes and quickly gave up. I think that's one reason sudoku appeals to me: I'm very poor at word puzzles.

My only comment, for what it's worth (which is negligible): former = reform.

My admiration also goes to Psuedo Kiwi who actually was able to construct these puzzles. I think you need to quickly submit a patent for your lexodu idea and then contact a puzzle-book publisher.

Updated: Corrected my spelling of lexodu

[Pseudo Kiwi]

Su bloko,

Sorry it's taken me a while to get back to you.
Well done on making such a gallant effort in solving the puzzle!

As you suspected, your "solution" isn't the same as mine. Unfortunately it's not a valid solution: in column 2 you have ORGRIV which doesn't give virago, and you also have DIENID in row 5 which isn't quite "indeed".

Anyway, I'm impressed you got close and were able to think of words like virago and ampere in the first place!

My solution by the way is:

Code: Select all

F O R  |  Z N E
E R M  |  I T H
-------+-------
N I S  |  G E S
E S P  |  A L E
-------+-------
D S E  |  N O C
R V I  |  L S E

That gives:
frozen, hermit, singes, please, second, silver
fender, visors, simper, lazing, stolen, cheese
former, zenith, spines, eagles, divers, clones

More than one solution? I think that's possible but fairly unlikely.

Regards
PK

[Darkozin]

Hi

Nice job on making Lexoku!

Congrats
-Darkozin-

[Pseudo Kiwi]

Hi all,

I know it was 2005 when I came up with my Lexoku idea, and it's now 2008, but I thought I'd let you know that my puzzle has been through a bit of an evolutionary process since my '05 effort. You can see the finished product (which has appeared in an Aussie puzzle magazine) on my website, at http://www.plutopuzzles.com/puzzles/lexoku/lexoku.htm

If you find Lexoku a bit daunting at first, there's a "hints" page, while if you find the puzzles too easy, I can certainly change that! For an additional challenge I also have Killer and Jigsaw versions in the pipeline.

On my site you'll also find some of my other original creations. I hope you enjoy them.

Any feedback would be greatly appreciated.

[HATMAN]

Thanks - an interesting looking set of puzzles.