SudokuSolver Forum

A forum for Sudoku enthusiasts to share puzzles, techniques and software
It is currently Thu Mar 28, 2024 1:07 pm

All times are UTC




Post new topic Reply to topic  [ 19 posts ]  Go to page Previous  1, 2
Author Message
PostPosted: Fri Jun 06, 2008 12:43 pm 
Offline
Grand Master
Grand Master
User avatar

Joined: Wed Apr 23, 2008 5:29 am
Posts: 302
Location: Sydney, Australia
Richard, here is a 6-cell cage which definitely needs a downward arrow: (edited to fix an embarassing typo :oops:)
Code:
..X
v.^
>>^

Of my scheme, the arrows don't point to the cage sum, instead they point to the neighbour (orthogonal or diagonal depending on cage structure) which share the same cage and has the smallest address (e.g topmost leftmost).

Afmob, your scheme is almost the same one the Puzzle Tiger software is using now. See here.

But they use 0-9,a-z,A-Z and you use 1-9 to represent singleton cages, so you only need 40 letters at most to represent the "proper cages", thus a-z,A-N (or A-Z,a-n) is enough.

Note this scheme is nothing new. As early as 2005/06 dukuso of the sudoku.com forum already wrote a killer program which uses this scheme. :geek:

I still prefer the 81-char arrow-string for the normal killers. Remote cages and overlap cages (and also repeat cages which Maurice likes a lot) are probably best dealt specially. As for the Puzzle Tiger/Afmob scheme, I really don't like the trouble to locate which letter representing which cage sum. :rambo:

_________________
ADYFNC HJPLI BVSM GgK Oa m


Last edited by udosuk on Fri Jun 06, 2008 1:21 pm, edited 1 time in total.

Top
 Profile  
Reply with quote  
PostPosted: Fri Jun 06, 2008 12:44 pm 
Offline
Expert
Expert

Joined: Sun Apr 27, 2008 10:44 am
Posts: 102
Location: Belgium
rcbroughton wrote:
if we're definig cage sum in the top left cell, do we need v ? we should only need to refer to a cell that is to the left or above, or if a cage starts in column 9, possibly to the right
I believe it's needed for 'U' shaped cages. The upper-right most cell is connected downward.
Code:
P v
^<<

Note: for clarity, I skipped the top center cell which belongs to some other cage

_________________
Jean-Christophe
"When you have eliminated the impossible, whatever remains, however improbable, must be the truth." Sherlock Holmes.


Top
 Profile  
Reply with quote  
PostPosted: Fri Jun 06, 2008 12:52 pm 
Offline
Expert
Expert

Joined: Sun Apr 27, 2008 10:44 am
Posts: 102
Location: Belgium
udosuk wrote:
Richard, here is a 6-cell cage which definitely needs a downward arrow:
Code:
..X
V.^
>>^


I do not see any downward arrow. Indeed it's an invalid puzzle since the UPPER CASE V defines a cage 31/1 :twisted: :rambo: :whistle:

_________________
Jean-Christophe
"When you have eliminated the impossible, whatever remains, however improbable, must be the truth." Sherlock Holmes.


Top
 Profile  
Reply with quote  
PostPosted: Fri Jun 06, 2008 1:19 pm 
Offline
Grand Master
Grand Master
User avatar

Joined: Wed Apr 23, 2008 5:29 am
Posts: 302
Location: Sydney, Australia
:bigoops: :bigoops: :bigoops:

With a pie in the face I'll go up and edit my cage. You can keep that code box in your quote as an evidence for my inexplicable blunder. :oops:

_________________
ADYFNC HJPLI BVSM GgK Oa m


Top
 Profile  
Reply with quote  
PostPosted: Fri Jun 06, 2008 1:34 pm 
Offline
Expert
Expert

Joined: Sun Apr 27, 2008 10:44 am
Posts: 102
Location: Belgium
rcbroughton wrote:
When I suggested \ / for diagonals, we only need to point either to the above left and above right cells.


How about a 'V' shaped cage of 3 ? The upper-right-most cell is connected left-downward.
Code:
E ,
 `


And for a '√' shaped cage of 4. The mid-left-most cell is connected right-downward
Code:
   K
. '
 '

_________________
Jean-Christophe
"When you have eliminated the impossible, whatever remains, however improbable, must be the truth." Sherlock Holmes.


Top
 Profile  
Reply with quote  
PostPosted: Fri Jun 06, 2008 2:31 pm 
Offline
Site Admin

Joined: Sun Apr 13, 2008 1:50 pm
Posts: 191
Location: London
You're right.

U shaped and O shaped cages occurred to me after I'd posted my comment . . .

The first versions of SudokuSolver, I saved cage information in human readable form following a convention of

XXaabbccdd;XXaabb;XXaabbccdd; . . .

where XX was the cage value and aa bb cc . . . were 01 - 81 to define the caged cells. This has the flexibility to handle any cage structure, including remote cages and overalpping cages, but at the expense of a minimm of 162 characters for the cells plus 3x number of cages. Slighlty morre economic than the PS format but with a degree more flexibility.


Top
 Profile  
Reply with quote  
 Post subject:
PostPosted: Fri Jun 06, 2008 4:09 pm 
Offline
Grand Master
Grand Master

Joined: Mon Apr 21, 2008 9:44 am
Posts: 310
Location: MV, Germany
You're right udosuk, this format is not new (like I said I've read about it before, but I didn't remember where) but I wanted to modify it, so that it's short (1-cell cages get directly defined by their numbers) and it's easy readible by programms and humans. It's about half the size of a normal PS code and also allows overlapping cages.

Udosuk and Tarek's format has the advantage that it's really short (less than half the size of my format if we use the identifier in front of the actual code) and it's easy to understand by humans but it cannot handle remote cages and overlapping cages (but I have to say that HS 1 is the only killer I've seen so far that has overlapping cages). And PS Code is standard so far and can handle remote cages but not overlapping cages and the code is really long and not understandable for humans.

Here are some examples of SudokuTiger's modified format I promised in my previous post:

A30 V2.1:
http://www.sudocue.net/forum/viewtopic.php?t=459
a a b b c d d e e
a f f f c g g g e
h f i i c j j g k
h f i l l l j g k
m m m l 3 l n n n
o p q l l l r s t
o p q q u r r s t
v p p p u s s s w
v v x x u y y w w

17, 16, 20, 7, 6, 22, 26, 10, 6, 21, 13, 42, 11, 18, 10, 31, 12, 16, 23, 9, 19, 17, 14, 9, 7

3x3::k:aabbcddeeafffcgggehfiicjjgkhfillljgkmmml3lnnnopqlllrstopqqurrstvpppussswvvxxuyyww::
17162007062226100621134211181031121623091917140907:

Human Solvable One:
http://www.rcbroughton.co.uk/sudoku/forum/viewtopic.php?f=3&t=73
a  b  a  c  c  c  d  e  d
b a f f g h h d e
a i a 0 g 0 d j d
0 i 0 k g l 0 j 0
m m m 0 kl 0 n n n
0 o 0 l p k 0 q 0
r o r 0 p 0 s q s
t r u u p v v s w
r t r x x x s w s

25, 7, 17, 25, 10, 13, 13, 12, 13, 12, 17, 10, 14, 10, 14, 15, 13, 25, 25, 6, 14, 13, 5, 16

3x3:d:k:abacccdedbaffghhdeaia0g0djd0i0kgl0j0mmm0:kl:0nnn0o0lpk0q0ror0p0sqstruupvvswrtrxxxsws::
250717251013131213121710141014151325250614130516:

Edit: To further shorten things we could also use letters for the cage sums (a=10,b=11, ...) but that might be confusing for humans since a,b, ... would have two meanings since it identifies a cage and a cage sum but those two properties are not necessarily connected (e.g. cage "a" might not have cage sum 10).


Top
 Profile  
Reply with quote  
PostPosted: Sat Jun 07, 2008 2:20 pm 
Offline
Grand Master
Grand Master
User avatar

Joined: Wed Apr 23, 2008 5:29 am
Posts: 302
Location: Sydney, Australia
Afmob, seeing you have posted a nice Assassin 106 with remote cages, I guess I have to take back my comment that remote cages were inelegant. BTW looking forward to your V2, as others have always solved V1. :)

_________________
ADYFNC HJPLI BVSM GgK Oa m


Top
 Profile  
Reply with quote  
PostPosted: Wed Jun 11, 2008 7:23 am 
Offline
Expert
Expert

Joined: Sun Apr 27, 2008 10:44 am
Posts: 102
Location: Belgium
I've added support in JSudoku for the 81 characters format (not released yet).
An identifier would have made the format easier to recognize but is not an absolute necessity. I currently detect this format when it contains at least one '<' and one '^'. When exporting, I follow Udosuk's order of preference which are maybe too restricted. For some cases, it's easier and faster for a program to scan and export if we allow '<' instead of '^' when both are valid.

_________________
Jean-Christophe
"When you have eliminated the impossible, whatever remains, however improbable, must be the truth." Sherlock Holmes.


Top
 Profile  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 19 posts ]  Go to page Previous  1, 2

All times are UTC


Who is online

Users browsing this forum: Google [Bot] and 5 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
cron
Powered by phpBB® Forum Software © phpBB Group