## Girandola

For fans of Killer Sudoku, Samurai Sudoku and other variants

### Girandola

I was wondering if this pattern has been posted somewhere before.....

it is a cross between windoku & 9-cell constraint (sort like Clover).....

To me it resembles Girandola fireworks. If anyone is interested, I could also post some puzzles following the rules of this sudoku variant

tarek

Last edited by tarek on Thu Dec 19, 2019 5:16 pm, edited 2 times in total.

tarek

Posts: 3747
Joined: 05 January 2006

The 5-cell overlap between the R159C159 Windoku group and the additional constraint forces 2 quads for the same 4 digits in R5C1289 and R1289C5. These should be taken into account when rating the difficulty.

tarek wrote:If anyone is interested, I could also post some puzzles following the rules of this sudoku variant

Bring 'em on!

Just figured out that the quads would also force R5C46 to contain the same digits as R37C5 and R5C37 the same as R46C5. This is a very restrained puzzle format.

Ruud
Ruud

Posts: 664
Joined: 28 October 2005

There is no overlap that i can see Ruud....
The Windoku groups (in blue) and the extra constraint in red

The clover has some overlap but not this one........

Could you elaborate a bit !!

tarek

tarek

Posts: 3747
Joined: 05 January 2006

hidden constraints for the Windoku variant:

2 boxes in rows 234 leaves 9 cells containing digits 1-9 (R234C159)
2 boxes in rows 678 leaves 9 cells containing digits 1-9 (R678C159)
2 boxes in columns 234 leaves 9 cells containing digits 1-9 (R159C234)
2 boxes in columns 678 leaves 9 cells containing digits 1-9 (R159C678)

4 windoku boxes + 4 hidden constraints leaves 9 cells containing digits 1-9 in R159C159.

This last constraint has 5 overlapping cells with your red cells. The remaining 4 cells have a LOL relationship, but since they are distributed 2 by 2 in R5 AND C5, we have the quads.

Ruud
Ruud

Posts: 664
Joined: 28 October 2005

thanx,

I'll try & generate some puzzles to see how this works out.

tarek

tarek

Posts: 3747
Joined: 05 January 2006

Tarek

If you are interested in Restrained Sudokus, I recently posted a very limited one on Ruud's site at

http://www.sudocue.net/forum/viewtopic.php?t=887

Maurice
HATMAN

Posts: 272
Joined: 25 February 2006
Location: Nigeria

I'm not quite sure what all the nonets are. For example, is R1C2345678 R3C5 R4C5 one of them?

Bill Smythe
Smythe Dakota

Posts: 565
Joined: 11 February 2006

My first Girandola

Code: Select all
`. . .|. . .|. . .. . 7|. . .|. . .. . .|5 . .|. . 3-----+-----+-----. . .|. . .|. . .. . .|. . .|. . 7. . .|. 5 8|. 1 .-----+-----+-----. . .|. . 4|. . .3 1 .|8 . .|. 6 .. . .|6 9 1|. . 5`

A light appetizer...

Ruud
Ruud

Posts: 664
Joined: 28 October 2005

Bill

I do not think so - but it is an obviuos likelyhood.

Maurice
HATMAN

Posts: 272
Joined: 25 February 2006
Location: Nigeria

Light as in "para"glider - all singles? (I mean the sport that I do occasionally - not him from {I've been chasing back on "para" - I thought he was from) the Netherlands but nothing is clearly stated,)
Last edited by HATMAN on Sat Jan 12, 2008 7:28 pm, edited 2 times in total.
HATMAN

Posts: 272
Joined: 25 February 2006
Location: Nigeria

[r5c8]: 9 is a hidden single for the Girandola group does it

Solution below:

193487652547263189268519743731946528685132497924758316856324971319875264472691835

will post some puzzle soon

tarek

tarek

Posts: 3747
Joined: 05 January 2006

Here is my 1st Girandola ........ More to come in the future.

Code: Select all
`901000605000000200240001009002000000000000000000000100100500062003000000408000903 9 . 1 | . . . | 6 . 5   . . . | . . . | 2 . .   2 4 . | . . 1 | . . 9  -------+-------+------  . . 2 | . . . | . . .   . . . | . . . | . . .   . . . | . . . | 1 . .  -------+-------+------  1 . . | 5 . . | . 6 2   . . 3 | . . . | . . .   4 . 8 | . . . | 9 . 3  `
It should be very easy

tarek
Last edited by tarek on Thu Dec 19, 2019 5:18 pm, edited 2 times in total.

tarek

Posts: 3747
Joined: 05 January 2006

tarek

With Restained Sudokus you have to limit the clues more severely
this one is human solvable with just the values in N1379
HATMAN

Posts: 272
Joined: 25 February 2006
Location: Nigeria

An optimized version of tarek's Girandola:

Code: Select all
`. . .|. . .|. . 5. . .|. . .|. . .. 4 .|. . .|. . 9-----+-----+-----. . 2|. . .|. . .. . .|. . .|. . .. . .|. . .|1 . .-----+-----+-----1 . .|. . .|. 6 2. . 3|. . .|. . .4 . 8|. . .|9 . 3`

Although it has a unique solution, I wonder if this is still human solvable...
Ruud

Posts: 664
Joined: 28 October 2005

Ruud,

you mentioned the LOL relationship between r28c5,r5c27 & r19c5,r5c19 which I understand....
But what is the quad you are talking about? (is it a LOLLOL )

regarding Minimal puzzles & Beyond human level:
Code: Select all
` . . 1 | . . . | . . .   . 9 3 | . . . | . 4 .   . . . | . . . | . 8 2  -------+-------+------  . . . | . . . | . . .   . . . | . . . | . . .   . . . | . . . | . . .  -------+-------+------  7 1 . | . . . | . . .   . 3 . | . . . | 5 1 .   . . . | . . . | 2 . .`

Another question, What do you call the regions .....
W1-4 is easy what about the other 5 hidden (do they have a name)?

tarek

[Edit: the above grid has multiple solutions produced due to a bug in my program which has been fixed]
Last edited by tarek on Sun Jan 13, 2008 10:21 pm, edited 1 time in total.

tarek

Posts: 3747
Joined: 05 January 2006

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