## Stuck on a Windoku

For fans of Killer Sudoku, Samurai Sudoku and other variants

### Stuck on a Windoku

I'm stuck on a Windoku:

Code: Select all
`.5.|...|......|...|.8.8..|.4.|1..---|---|---...|...|2...38|6.2|.9..96|1..|...---|---|---...|..3|.1....|...|...92.|...|3..`

My current stage:

Code: Select all
`+-----------------------+-----------------------+-----------------------+|(37)      5     (1479) |(79)    (2678)  (18)   |(467)   (467)   (2367) ||(137)   (1467)  (2479) |(3579)  (12567) (567)  |(45679)   8     (235679)|  8     (67)    (279)  |(3579)    4     (567)  |  1     (357)   (235679)+-----------------------+-----------------------+-----------------------+|(157)   (147)   (57)   |  8     (39)    (49)   |  2     (346)   (136)  ||(14)      3       8    |  6     (57)      2    |(57)      9     (14)   ||  2       9       6    |  1     (357)   (457)  |(4578)  (47)    (34578)|+-----------------------+-----------------------+-----------------------+|(4567)  (478)   (457)  |  2     (78)      3    |(46789)   1     (4789) ||(16)    (478)     3    |(457)   (15789) (5679) |(4678)    2     (4578) ||  9       2     (147)  |(47)    (5678)  (18)   |  3     (4567)  (5678) |+-----------------------+-----------------------+-----------------------+`

How should I proceed?
There should be a pointing pair or n-tuple.
evert on the crashed forum

dyitto

Posts: 118
Joined: 22 May 2010
Location: Amsterdam

### Re: Stuck on a Windoku

Hidden triple N2, pointing pair later
HATMAN

Posts: 219
Joined: 25 February 2006

### Re: Stuck on a Windoku

You mean the 2nd extra group R24C68?
I still don't sea a triple in (567) (45679) (567) (357) (49) (346).
Which numbers?
evert on the crashed forum

dyitto

Posts: 118
Joined: 22 May 2010
Location: Amsterdam

### Re: Stuck on a Windoku

Nah. He means Block 2.
Once upon a time I was a teenager who was active on here 2007-2011
ocean and eleven should have paired up to make a sudoku-solving duo called Ocean's Eleven
999_Springs

Posts: 473
Joined: 27 January 2007
Location: In the toilet, flushing down springs, one by one.

### Re: Stuck on a Windoku

Ah box 2 numbers 1,2,8
OK thanks!!
evert on the crashed forum

dyitto

Posts: 118
Joined: 22 May 2010
Location: Amsterdam

### Re: Stuck on a Windoku

I've alway used N for Nonet, but there does not appear to be a standard numbering for windoku either.
HATMAN

Posts: 219
Joined: 25 February 2006

### Re: Stuck on a Windoku

.5..............8.8...4.1........2...386.2.9..961..........3.1..........92....3..

359781462147326985862945173715894236438652791296137548584273619673519824921468357

Code: Select all
`13467 ```5 12479 | `379 1236789 `16789 | ``4679 `3467 `234679 13467 1467 12479 | 3579 1235679 ``5679 | `45679 ````8 2345679 ````8 ``67 ``279 | 3579 ``````4 ``5679 | `````1 `3567 `235679 -----------------+---------------------+----------------------`1457 `147 `1457 | ```8 ```3579 ``4579 | `````2 34567 `134567 `1457 ```3 ````8 | ```6 `````57 `````2 | ```457 ````9 ```1457 ````2 ```9 ````6 | ```1 ````357 ```457 | ``4578 ``457 ``34578 -----------------+---------------------+----------------------`4567 `478 ``457 | ```2 ``56789 `````3 | 456789 ````1 `456789 14567 `478 ````3 | `457 `156789 456789 | 456789 ````2 `456789 ````9 ```2 `1457 | `457 ``15678 145678 | `````3 `4567 ``45678 `

I call the extra houses in the puzzle "windows" and number them w1, w2, w3 and w4

b2.14679 {-128}.235 // hidden triple in box2
c2 {1} w1.28 // claiming: column2 claims all the candidate {1} from the rest of window1
w1 {2} b1.3 c3.1 // window1 claims all the candidate {3} from box1 and column3
w1 {3} b2.1 c4.1
w2 {3} c8.1
b5 {4} c6.89
{4} r8c1 % w3 // r8c1 cannot have candidate {4} as then w3 is devoid of candidate {4}'s
{5} r7c5 % w3
{5} r8c1 % w3
b2 {6} c6.89 w2.269
b7 {6} c1.12
w4 {6} b9.3689 c7.1
{7} r8c1 % w3
c7 {8} w4.7
c4 {9} b2.69
{9} r8c9 % w4

--assert singles--
Code: Select all
`1347 ```5 1479 | ``79 ``128 ``18 | ```479 ```6 `23479 1347 1467 2479 | 3579 ```12 `567 | ``4579 ```8 234579 ```8 ``67 `279 | 3579 ````4 `567 | `````1 `357 `23579 ---------------+-----------------+--------------------1457 `147 `457 | ```8 `3579 4579 | `````2 3457 `````6 `457 ```3 ```8 | ```6 ```57 ```2 | ```457 ```9 `````1 ```2 ```9 ```6 | ```1 ``357 `457 | ``4578 `457 `34578 ---------------+-----------------+--------------------4567 `478 `457 | ```2 ``789 ```3 | 456789 ```1 `45789 ``16 `478 ```3 | `457 15789 `579 | 456789 ```2 ``4578 ```9 ```2 1457 | `457 ````6 1578 | `````3 `457 ``4578 `

c6.23468 {-18}.(1)9

col 2f c36 {1} : r19 // x-wing (2-fish) in the columns 3 and 6 over rows 1 and 9
ff {4} r7c7 % c68 > r4 // finned fish: r7c7 cannot have candidate {4} because then columns 6 and 8 only has the candidate {4} in r4 [it needs to be in at least two places]
ff {4} r8c7 % c68 > r4

w4 {4} r6.9

r3.268 -3- r4.1238 {5} r4c6 // als-xz move, the restricted common is {3} between the sets r3 positions 2 6 and 8 and r4 positions 1 2 3 and 8. the {5} in r4c6 touches all the {5}'s in both sets
r4.123 -4- w2.1469 {7} r4c6

Code: Select all
``347 ```5 1479 | ``79 ```28 `18 | ``479 ```6 `23479 1347 1467 2479 | 3579 ```12 567 | `4579 ```8 234579 ```8 ``67 `279 | 3579 ````4 567 | ````1 `357 `23579 ---------------+----------------+-------------------1457 `147 `457 | ```8 `3579 `49 | ````2 3457 `````6 `457 ```3 ```8 | ```6 ```57 ``2 | ``457 ```9 `````1 ```2 ```9 ```6 | ```1 ``357 457 | `4578 `457 ``3578 ---------------+----------------+-------------------4567 `478 `457 | ```2 ``789 ``3 | 56789 ```1 `45789 ``16 `478 ```3 | `457 15789 579 | 56789 ```2 ``4578 ```9 ```2 1457 | `457 ````6 `18 | ````3 `457 ``4578 `

at this point, I do not have a definite solution step; however I notice that speculating a {5} to r8c4 gives:

Code: Select all
```3 ```5 479 | `79 ``8 ``1 | `479 ``6 ````2 147 1467 479 | 379 ``2 567 | 4579 ``8 34579 ``8 ``67 ``2 | 379 ``4 567 | ```1 357 `3579 -------------+-------------+----------------147 `147 ``5 | ``8 379 `49 | ```2 347 ````6 `47 ```3 ``8 | ``6 `57 ``2 | `457 ``9 ````1 ``2 ```9 ``6 | ``1 357 457 | 4578 457 `3578 -------------+-------------+----------------``5 `478 `47 | ``2 `79 ``3 | ```6 ``1 `4789 ``6 `478 ``3 | ``5 ``1 `79 | `789 ``2 ``478 ``9 ```2 ``1 | ``4 ``6 ``8 | ```3 `57 ```57 `

b2.147 {-56}.69 // hidden pair {56} in box 2
b9.89 {57}.346 // naked pair {57} in box 9
c6.23 {56}.6 // naked pair {56] in column 6
w2.14 {56}.26 // hidden pair {56} in window 2
b9 {4} c9.2
c8 {4} b6.47
b3 {5} c9.69

Code: Select all
```3 ```5 479 | `79 ``8 `1 | 479 ``6 ```2 147 1467 479 | 379 ``2 56 | 479 ``8 3579 ``8 ``67 ``2 | 379 ``4 56 | ``1 `37 3579 -------------+------------+--------------147 `147 ``5 | ``8 379 49 | ``2 347 ```6 `47 ```3 ``8 | ``6 `57 `2 | `57 ``9 ```1 ``2 ```9 ``6 | ``1 357 47 | 578 457 `378 -------------+------------+--------------``5 `478 `47 | ``2 `79 `3 | ``6 ``1 `489 ``6 `478 ``3 | ``5 ``1 79 | `89 ``2 ``48 ``9 ```2 ``1 | ``4 ``6 `8 | ``3 `57 ```7 `

here singles solve.

There is one other position for a {5} in window 3, so trying that....

Code: Select all
``347 ```5 1479 | ``79 ```28 `18 | ``479 ```6 `23479 1347 1467 2479 | 3579 ```12 567 | `4579 ```8 234579 ```8 ``67 `279 | 3579 ````4 567 | ````1 `357 `23579 ---------------+----------------+-------------------1457 `147 ``47 | ```8 `3579 `49 | ````2 3457 `````6 `457 ```3 ```8 | ```6 ```57 ``2 | ``457 ```9 `````1 ```2 ```9 ```6 | ```1 ``357 457 | `4578 `457 ``3578 ---------------+----------------+-------------------`467 `478 ```5 | ```2 ``789 ``3 | `6789 ```1 ``4789 ``16 `478 ```3 | ``47 15789 579 | 56789 ```2 ``4578 ```9 ```2 `147 | `457 ````6 `18 | ````3 `457 ``4578 `

w1.1478 {1467}.2356
w1.124578 {-35}.36
r3.2468 {-29}.(3)9
b1.69 {29}.3
b2.47 {35}.69
b2.69 {67}.1

r3.26 {67}.8
b8.47 {47}.256
c6.23 {67}.6
w2.14 {67}.29

r9 {5} b9.46
c6 {5} w4.23
{5} r4c8 % c7
w2 {5} b3.6
{7} r7c7 % c8
{7} r8c7 % c8
w4 {7} r6.59 b6.49

r8.249 {478}.57

r1.7 -7- b6.2479 {4} r2c7
r2.6 =67= w2.24679 {4} r4c1
r2.6 =67= w2.24679 {4} r4c2
r2.6 =67= w2.24679 {4} r4c3

assert singles

Code: Select all
`37 `5 1 | `9 `2 `8 | `47 `6 `347 37 `4 2 | 35 `1 `6 | ``9 `8 ``37 `8 `6 9 | 35 `4 `7 | ``1 `3 ```2 --------+----------+-------------`5 `1 7 | `8 39 `4 | ``2 `3 ```6 `4 `3 8 | `6 `7 `2 | ``5 `9 ```1 `2 `9 6 | `1 35 `5 | 478 47 ``38 --------+----------+-------------67 78 5 | `2 89 `3 | ``8 `1 4789 `1 78 3 | `4 59 59 | ``6 `2 ``78 `9 `2 4 | `7 `6 `1 | ``3 `5 ```8 `

box3 and column9 both lack placements for the {5} so r7c3 cannot have the {5} placed, thus the solution above is unique.
leeo

Posts: 1
Joined: 28 September 2010

### Re: Stuck on a Windoku

Leeo

The point about the numbering is that there are 5 implied windows which simplify solving.

Your w1&w2 contain (1 to 9)*2 but r234 contains (1 to 9)*3 hence r234c159 contains 1 to 9.

As you demonstrate the puzzle can always be solved without utilising these hidden windows - but it is generally much harder.

Maurice
HATMAN

Posts: 219
Joined: 25 February 2006