The New Sudoku Players' Forum

by **urhegyi** » Mon Feb 01, 2021 4:11 pm

Situation can be reproduced with this simple sudoku:

Code: Select all: #1//B4,N .51.247894728.9.6..9817.24.21948..3.86.29.4..74..619289847....2.269.8.74.37.4289.

I expect when solving by hand that SiseSuSo will do it the same way with 2xy-wings, but it needs first 2 xy-chains which are harder and then the xy-wings.

Code: Select all: Pointing, Claiming | (3)b9c7 => (-3)r2c7 XY_Chain r | (5=3)r3c9 (3=6)r3c1 (6=3)r1c1 (3=6)r1c4 (6=5)r9c4 [5] => (-5)r9c9 XY_Chain b | (5=3)r2c5 (3=6)r1c4 (6=5)r9c4 (5=1)r9c1 (1=5)r8c1 [5] => (-5)r8c5 XY-Wing r | (1=5)r2c7 (5=3)r2c5 (3=1)r8c5 [3] => (-1)r8c7 XY-Wing b | (1=5)r7c8 (5=3)r8c7 (3=1)r8c5 [3] => (-1)r7c5

Why checks it first for chains instead of wings which are lower rated?

There is a simple xy-wing to start with at R1C4,R2C5,R9C4: R1C4=3--> R2C5=5; R1C4=6--> R9C4=5; R78C5<>5

by **Hajime** » Mon Feb 01, 2021 5:45 pm

I will look this into it...

by **Hajime** » Wed Feb 03, 2021 12:13 pm

urhegyi wrote:There is a simple xy-wing to start with at R1C4,R2C5,R9C4: R1C4=3--> R2C5=5; R1C4=6--> R9C4=5; R78C5<>5

You are right.
The program only eliminates candidates in seeing cells of the same row/col of the XY-chain/wing. It should also test seeing cells in the same box.
R1C4,R2C5,R9C4: two 5-s at the ends of the chain/wing --> r7c5<>5 and r6c5<>5
I will repair this in the next version.
Thanks

by **urhegyi** » Wed Feb 03, 2021 10:59 pm

Resize the browser ruins the picture produced by your "to html" option. To avoid this a simple fix in your html code:
first five lines
old:

Code: Select all: <!DOCTYPE html> <html><body> <style>table, th, td { border-collapse: collapse; text-align: center; table-layout: fixed; width:100%; } td { }

new:

Code: Select all: <!DOCTYPE html> <html><body> <style>table { border-collapse: collapse; table-layout: fixed; text-align: center; } th { width:100%; padding-bottom:100%; } td { }

by **Hajime** » Thu Feb 04, 2021 2:56 pm

urhegyi wrote:Resize the browser ruins the picture produced by your "to html" option. To avoid this a simple fix in your html code:
first five lines

Looks great, Thanks urhegyi. Will be implemented in the next version of SiSeSuSo.
And for everybody else: you can zoom in/out by holding down the Ctrl-key and scroll the mouse-wheel...
How it looks now: jigsaw asterisk ninja.
Hmmm, dropbox-link does work direct on Windows but not on Android (download and open) :shock:

In code:

Hidden Text: Show

Basic methods and some Generalized Intersections needed

by **urhegyi** » Tue Mar 02, 2021 12:53 am

Hajime wrote:
urhegyi wrote:There is a simple xy-wing to start with at R1C4,R2C5,R9C4: R1C4=3--> R2C5=5; R1C4=6--> R9C4=5; R78C5<>5

You are right.
The program only eliminates candidates in seeing cells of the same row/col of the XY-chain/wing. It should also test seeing cells in the same box.
R1C4,R2C5,R9C4: two 5-s at the ends of the chain/wing --> r7c5<>5 and r6c5<>5
I will repair this in the next version.
Thanks

I found another case where a simple xy-wing wasn't found.
Could you check it with your latest version. The latest public one still has this bug.

: SiSeSuSo_20210302_014253.png (16.6 KiB) Viewed 20 times

1)IF R9C4 = 2 --> R9C7=6
ELSE IF R9C4=7 --> R8C5=6
--> R8C9<>6=7!
2)IF R9C7 = 2 --> R9C4=7
ELSE IF R9C7 = 6 --> R8C9 = 7
--> R8C5<>7=6!
This all is tested with the February version.
I see now the March version is available.
Will test it later.
Update: Fixed

The New Sudoku Players' Forum

SiSeSuSo questions/bugs

SiSeSuSo questions/bugs

Re: SiSeSuSo questions/bugs

Re: SiSeSuSo questions/bugs

Re: SiSeSuSo questions/bugs

Re: SiSeSuSo questions/bugs

Re: SiSeSuSo questions/bugs