View previous topic :: View next topic |
Author |
Message |
ZeroAssoluto
Joined: 05 Feb 2017 Posts: 942 Location: Rimini, Italy
|
Posted: Thu Oct 14, 2021 9:21 am Post subject: Oct 14 VH |
|
|
Hi everyone,
Code: |
+------------+-------------+----------+
| 7 5 9 | 26 36 236 | 48 1 48 |
| 1 8 3 | 7 9 4 | 6 5 2 |
| 6 2 4 | 5 8 1 | 9 7 3 |
+------------+-------------+----------+
| 5 49 18 | 269 136 236 | 23 48 7 |
| 3 6 2 | 4 7 8 | 5 9 1 |
| 89 479 178 | 29 135 235 | 23 48 6 |
+------------+-------------+----------+
| 4 3 78 | 1 2 9 | 78 6 5 |
| 2 1 5 | 8 46 67 | 47 3 9 |
| 89 79 6 | 3 45 57 | 1 2 48 |
+------------+-------------+----------+
|
Play this puzzle online at the Daily Sudoku site
Quote: | XY-Wing 4,8,9 in r4c28,r6c1 and -8 in r4c3,r6c8
or
XY-Wing 4,8,9 in r4c2,r6c18 and -4 in r4c8,r6c2 |
Ciao Gianni |
|
Back to top |
|
|
TomC
Joined: 30 Oct 2020 Posts: 358 Location: Wales
|
Posted: Thu Oct 14, 2021 10:51 am Post subject: |
|
|
One of the XY wings solved it for me.
On reflection, I noticed a conflict in row 4
In r4c4 you have 269, if it is a 2 or 6 this would give r4c3=1 and in that case the puzzle would be invalid.
So r4c4 = 9 |
|
Back to top |
|
|
ZeroAssoluto
Joined: 05 Feb 2017 Posts: 942 Location: Rimini, Italy
|
Posted: Thu Oct 14, 2021 12:25 pm Post subject: |
|
|
Which XY-Wing is not working? |
|
Back to top |
|
|
TomC
Joined: 30 Oct 2020 Posts: 358 Location: Wales
|
Posted: Thu Oct 14, 2021 12:46 pm Post subject: |
|
|
Gianni,
Both your XY wings produce a solution, if I find one which solves the puzzle I rarely look for a different one.
I offer a different view to produce a solution.
Tom |
|
Back to top |
|
|
ZeroAssoluto
Joined: 05 Feb 2017 Posts: 942 Location: Rimini, Italy
|
Posted: Thu Oct 14, 2021 12:57 pm Post subject: |
|
|
👌 |
|
Back to top |
|
|
Mogulmeister
Joined: 03 May 2007 Posts: 1151
|
Posted: Fri Oct 15, 2021 8:46 am Post subject: |
|
|
TomC wrote: | One of the XY wings solved it for me.
On reflection, I noticed a conflict in row 4
In r4c4 you have 269, if it is a 2 or 6 this would give r4c3=1 and in that case the puzzle would be invalid.
So r4c4 = 9 |
Nice one Tom - I think I understand but of course r4c3 does equal 1 doesn't it ? |
|
Back to top |
|
|
TomC
Joined: 30 Oct 2020 Posts: 358 Location: Wales
|
Posted: Fri Oct 15, 2021 9:37 am Post subject: |
|
|
This was hard for me to describe, I'll try again
If r4c4 is either 2 or 6 then r6c4=9, r6c1=8, r4c3=1
this would then give row 4 to be
either
| 5 49 1 | 2 36 36 | 2 48 7 | (two 2's in row4)
or
| 5 49 1 | 6 3 2 | 3 48 7 | (two 3's in row4)
so r4c4 must be 9
also r4c3 is 1 but not if r4c4 is 2 or 6
Describing this is harder than how I saw this in the first place! |
|
Back to top |
|
|
Mogulmeister
Joined: 03 May 2007 Posts: 1151
|
Posted: Fri Oct 15, 2021 10:02 am Post subject: |
|
|
TomC wrote: |
Describing this is harder than how I saw this in the first place! |
Yes - a common problem for us all ! |
|
Back to top |
|
|
Mogulmeister
Joined: 03 May 2007 Posts: 1151
|
Posted: Fri Oct 15, 2021 10:40 am Post subject: |
|
|
Mogulmeister wrote: | I showed the two sides of the ANP in this way to mirror the analysis of something that takes seconds by inspection but far longer to write down !
|
From a while back….. |
|
Back to top |
|
|
|