The New Sudoku Players' Forum

by **wapati** » Fri Jan 05, 2007 5:42 am

Another swordfish. You can avoid it if you just NEVER see them.
A second xy will slide you through. The sword is visible early and survives intact several other patterns!

Code: Select all: . . 7 | 4 5 . | 3 . . . . 5 | . . 8 | . . . 6 2 . | . . . | . . 5 --------------------- 7 . . | . 4 1 | . 8 . 3 . . | 8 . 5 | . . 4 . 8 . | 7 6 . | . . 3 --------------------- 2 . . | . . . | . 3 7 . . . | 5 . . | 6 . . . . 8 | . 2 3 | 9 . .

by **daj95376** » Fri Jan 05, 2007 5:43 am

wapati,

I'm glad that you enjoyed the Swordfish. I hope you enjoy these Jellyfish as well. To answer your question, my puzzle generator only generates puzzles that are 180 degree symmetrical. It was a common practice when I started Sudoku, and I still prefer it this way.

When it comes to generating Swordfish and Jellyfish, I find that blocking a digit from appearing in the clues works best in my puzzle generator. If you look closely, several of these puzzles have the same solution. However, they are completely different puzzles in the solution path and the Jellyfish found.

===== ===== ===== Jellyfish

Code: Select all: 4....521..3..8.4....54....8..21.....589...126.....69..2....13....6.2..4..435....2 4.8.1..2.6..3.8.1...92...3..46...2.....6.1.....1...89..8...43...6.7.3..9.1..8.7.4 56218....7...6.....1.4....6...6.917.9.......2.567.4...4....8.5.....9...8....46291 ...1....9..4.6.31.3..4..8..238.......4.....6.......983..3..8..7.21.9.4..8....6... 7.....63..42..8.......34..81....35...58...14...78....25..28.......1..32..14.....5 .2..65.9.85.........1..32....2..7..61...8...57..3..9....61..3.........68.3.27..1. 3..4....1.5..2.6...418..2..48..5....1.3...4.5....1..82..6..832...4.3..6.9....6..4 .....45....8.2...44..6.378.8......6..2.578.4..4......5.843.2..79...6.4....39..... 67..........6713...43..8...9....4.5.7.5.1.8.4.1.9....3...4..91...8769..........68 ...76.....261....8..4.3.1.94.9......7...1...3......9.41.3.8.7..6....139.....73... .....6..4...3..6..2.95..8.3.57.9....49.....87....7.36.9.4..32.5..2..4...5..9..... 1.5..67...4.3..65.....4....3..6...2.4.6...5.7.2...5..9....6.....12..4.3...39..1.6 .329..4...8.3..26.4.9......3...47.28.........97.58...3......7.6.64..9.5...7..639. 6.29.8.1.....1.2.941..........1....8.4.693.7.9....2..........868.4.3.....2.8.63.4 3591..2..42.73...........5..359......8.....1......347..9...........97.28..7..1945 8.1..6..375...9........856....37..2.3.......5.7..65....985........9...381..6..9.2 8..7.6....5.....8..3..2...761....8....42.16....2....142...1..4..6.....3....6.7..2 ....5138.12...8..6..3.....2.31.4...8...8.9...9...3.42.2.....8..3..6...15.1692.... 76........2...85...834....2..1.4..5.4.2.1.6.7.7..3.4..2....386...76...1........43 ....1...2.51..8...6.2.4..9.3.9...24.1.......8.28...5.9.9..2.4.6...3..91.8...6.... 16..97......8....15.32....7..23..6..68.....35..7..61..7....92.68....3......72..13 1.849.....7.........32.18..9......78..41.29..35......4..15.92.........4.....285.3 6.....9.7.156.9...7.83...6......647..6.5.7.1..874......5...48.1...9.864.8.9.....5 6.....9...15.7..8.79..4..6...1..6.7.4..5.7..8.8.4..5...5..2..91.7..5.64...9.....5 ..4...1...1..78..6..6....45...7.9.3..95...81..8.5.1...76....9..1..65..8...8...6.. 547..28...3.....7...6.9...3..4..8.32.5.....4.27.5..9..4...6.3...2.....9...59..784 5..3..8...3..8......6.94.5..9.17..3..5.....4..7..46.1..1.86.3......5..9...5..1..4 ...2.....5.9.7.41.41.6.......8..714.....2.....751..9.......2.58.92.8.7.1.....1... ...7.18..3.....2..857..9.1..1..4.7..4..9.5..2..9.8..4..7.2..984..3.....5..25.4... .3....5...6.2.....7.593...65..7...61..76.23..69...3..41...297.3.....7.5...9....4. ...32...9.3...7.1...89..4..4.1..9....8.....6....1..3.2..9..87...2.4...9.6...92... 9...6...4.64..75...3...97....34...9.2.......6.5...68....67...5...29..68.3...8...7 .2...5....6...7.2...1.4..686.....2.524.....767.9.....148..1.9...7.9...8....6...1. .2.8....4......52..31..9..8....7..95..85913..75..2....4..7..95..72......3....2.1. 6.7.9.1...8....4.9..96.1....2.1..6.8...7.5...4.6..8.7....2.48..8.4....2...2.1.9.7 8..4....36....1.8..31..74...958....7.7..1..5.4....583...97..31..1.5....87....6..4 ..56.9...36..2.....79.....69...6.4.55..3.7..22.7.5...36.....82.....8..54...2.49.. .......38.6...85....95.32.6.1...2..5.46.9.18.2..4...9.6.49.58....21...5.15....... .9.2..7..86.7......579.83..5.....6..73..6..89..6.....2..56.182......5.71..8..7.5. 4......8..62.9..4...8..65.7..4.69...7..1.8..2...75.8..9.56..4...8..7.26..4......1 ..27..9.454..3.1..98.1......3..95.....83.12.....84..5......7.81..1.8..928.5..93.. .1..4..52.4.9.7...7...5.9..39....2....42193....1....94..5.6...9...5.4.2.46..2..1. ..7.5.6.19....1.5.6..8...37...52..7..9.....8..7..68...76...5..3.8.2....95.9.1.7.. ..73.26..9..67...4..1.9.23.4.8..9...............1..9.2.62.8.4..1...37..9..94.67.. 94....3.....5.......2.38..9.5.....34...294...81.....9.6..82.9.......1.....5....16 12..4....8.51.2.4...3........93.6.8...1.9.5...8.5.16........2...4.6.89.5....3..64 12.9.......5.6......37.5.9..5..764.16.......33.452..7..3.4.72......1.9.......9.64 5..8.1.97.1.3...5.....5.2.8...2..54.....3.....93..8...9.2.8.....7...5.3.13.7.9..4 .2...6.4...8.2....5....8.7...69..4..28.....67..4..28...7.2....5....3.6...6.4...2. 9...1.3.8...7.....5.13.8.7.7.....4....51.39....4.....1.7.2.91.5.....7...8.9.5...3 927..6..........1....3..2.67..9.5.3.2.5.4.9.7.9.6.2..14.3..9....5..........4..723 .....2...3.....4.2....957...32..1.6.4.1...3.7.6.4..25...916....7.6.....3...5..... .627....835...6.97...5..2...35........46973........82...7..2...92.3...855....897. .6.8......48.239..32....8..43......8.5.678.4.8......29..2....57..376.29......2.8. .6.8....2.4..23.7.3....68..4..29....2.9...1.3....34..9..24....7.8.76..9.7....2.8. 9..8.74.2...5...7.32....8...312....8....7....8....452...2....57.8...1...7.43.2..1 6...74..9.9...64..7.459..2..2.....43..8...9..93.....7..6..857.4..59...6.3..26...8 ..178.9...7..56..8..3..1.6...25.....3.......7.....95...5.3..2..8..67..1...6.928.. ....839.44.9..6....83....626..5..48...........48..9..395....24....6..3.91.649.... 8.34.2..6.5..7......29.....6..8..5..27..6..39..5..7..8.....96......3..4.9..7.48.3 89...27..1.6...2....29.6..56.98...2.....6.....3...71.83..5.96....7...9.2..17...53 4..3....86...5..2....6.45.3.2...5.6...1...9...6.9...8.3.54.9....1..8...52....6..9 ..859....9....4..13.....59..23.79....4.8.5.2....32.47..57.....24..9....8....531.. ..5.897.297..6.....8.....1.7..8..36...........63..7..1.1.....9.....7..268.629.1.. .3........7.46...84...5.61.7..8..364.4..2..5.563..7..1.17.3...53...71.2........7. ..9.15.7...4..89.565..9....94.6.....2.......1.....2.49....8..247.24..5...8.52.6.. .42......5..41.2...8..6..5...51..4...6.....3...4..28...1..5..6...9.31..8......31. ......37.18...6...2...5.9....87..5.9...389...7.9..26....6.7...1...6...95.52...... 8.......1.9.3...4..6..9...5.1697.....8.1.5.9.....3861.4...5..8..7...9.3.9.......6 8....7.6..9..1.8.2.6.89.3...1.97....78.1.5.93....38.1...1.53.8.6.5.8..3..3.7....6 ..352.9.1.973...4........7.31...2.5...41.52...5.4...17.2........7...913.9.8.415.. 84.........7...8.2..28.4..53.6..2.5....1.5....5.4..6.74..6.37..6.5...1.........26 46.7.1.3.5.....1...3.2.9.6..23.1....9.1.6.4.3....9.21..5.1.6.4...4.....5.9.4.5.21 ..41.87.9.1...7..697.....8.......21.2...4...8.51.......4.....651..4...2.6.97.58.. .....9.3.....2.64...34....58..73.5.635.6.8.977.6.95..35....43...37.5.....8.9..... 4...1.....95..7..827.4...1......1.26...648...71.2......2...4.799..1..86.....7...1 5...8.....9.5.1..62.8.....9...96..5.36..4..18.2..18...9.....3.51..4.3.8.....5...1 53.7...424.7....36.....45......6.2.3...245...7.5.1......41.....15....6.767...2.91 .5837...4.4.8.9...3.71...9....4..7..5.4...6.8..3..1....3...84.1...7.5.8.8...4397. 9..3..1....1...5...6..5..921.9.26...52.....18...58.2.973..9..2...2...3....6..3..5 ...32.5..51.........8..5.4.79.2.84....4.9.8....25.4.93.4.1..9.........21..7.59... ...9..4.....62..9...574...8.9..5.86..6.....4..82.6..3.7...345...4..76.....3..8... 12.9......7.62......5...6..4....7..2..7.1.9..5..4....1..9...5......76.1......8.74 ......45..7.62.......7....84.1.5.8..3..8.2..5..2.6.7.17....4.......76.1..53...... ....48.5989.3..7...1.7..8..54.6...2...........7...1.95..8..5.7...6..7.1415.46.... .6.1.8..98.5.2....3...5.....4.6......81.9.63......1.9.....1...6....3.5.41..4.2.8.

by **Carcul** » Fri Jan 05, 2007 11:38 am

Wapati wrote:An xyz and a Swordfish. (I like swordfish!)

Code: Select all: *---------------------------------------------------------------------* | 456 3 457 | 45 9 2 | 14678 146 1468 | | 1 27 247 | 34 8 367 | 9 5 346 | | 456 8 9 | 1 56 367 | 3467 2 346 | |----------------------+---------------------+------------------------| | 25 125 6 | 9 3 8 | 145 14 7 | | 7 4 3 | 6 1 5 | 2 8 9 | | 8 9 15 | 7 2 4 | 156 3 156 | |----------------------+---------------------+------------------------| | 3459 157 1457 | 2 56 369 | 134568 1469 134568 | | 3459 6 8 | 35 7 1 | 345 49 2 | | 2359 125 125 | 8 4 369 | 1356 7 1356 | *---------------------------------------------------------------------*

[r1c8]-6-[r1c1]=6|7=[r1c3]-7-[r2c23]=7|6=[r2c9]-6-[r1c8], => r1c8<>6 and the puzzle is solved.

Carcul

by **Carcul** » Fri Jan 05, 2007 1:01 pm

Wapati wrote:Another Swordfish, with xy-wing. Mmm-Mmmm, swordfish is tasty!

Code: Select all: *---------------------------------------------------------------* | 6 47 2 | 35 8 3457 | 37 9 1 | | 47 1 5 | 236 9 2347 | 28 46 2378 | | 9 3 8 | 26 47 1 | 5 46 27 | |-------------------+---------------------+---------------------| | 57 579 379 | 359 2 8 | 4 1 6 | | 158 2 139 | 4 3567 35679 | 89 357 3578 | | 58 6 4 | 1 357 3579 | 289 357 23578 | |-------------------+---------------------+---------------------| | 247 8 6 | 239 34 2349 | 1 357 357 | | 3 457 17 | 8 1456 456 | 67 2 9 | | 125 59 19 | 7 1356 2356 | 36 8 4 | *---------------------------------------------------------------*

1. [r3c9]-7-[r3c5]-4-[r7c5]-3-[r7c89]=3=[r9c7]-3-[r1c7]-7-[r3c9], => r3c9<>7.

2. [r5c1]=1=[r9c1]-1-[r8c3]-7-[r8c7]=7=[r1c7]-7-[r1c2]=7=[r2c1]-7-
-[r46c1]-5,8-[r5c1], => r5c1<>5,8 and the puzzle is solved.

Carcul

by **udosuk** » Fri Jan 05, 2007 1:06 pm

Carcul wrote:
Code: Select all
*---------------------------------------------------------------------* | 456 3 457 | 45 9 2 | 14678 146 1468 | | 1 27 247 | 34 8 367 | 9 5 346 | | 456 8 9 | 1 56 367 | 3467 2 346 | |----------------------+---------------------+------------------------| | 25 125 6 | 9 3 8 | 145 14 7 | | 7 4 3 | 6 1 5 | 2 8 9 | | 8 9 15 | 7 2 4 | 156 3 156 | |----------------------+---------------------+------------------------| | 3459 157 1457 | 2 56 369 | 134568 1469 134568 | | 3459 6 8 | 35 7 1 | 345 49 2 | | 2359 125 125 | 8 4 369 | 1356 7 1356 | *---------------------------------------------------------------------*

[r1c8]-6-[r1c1]=6|7=[r1c3]-7-[r2c23]=7|6=[r2c9]-6-[r1c8], => r1c8<>6 and the puzzle is solved.

Just feel like to interpret Carcul's nice loop notation with a more straight forward step-by-step description:

If r1c8=6
=> r1c1<>6
=> naked pair {45} in r1c14
=> r1c3=7
=> r2c23<>7
=> naked triple {234} in r2c234
=> r2c9=6
=> Contradiction: two 6s in b3 (r1c8 & r2c9)!

Therefore r1c8<>6 => r7c8=6 and the rest are all singles... :idea:

by **Carcul** » Fri Jan 05, 2007 1:24 pm

Wapati wrote:Here is some xy practice. There are 5 followed by a sky/Turbot.

Code: Select all: *--------------------------------------------------------------* | 356 23 2568 | 1 258 7 | 9 4 568 | | 56 1 7 | 9 458 456 | 2 58 3 | | 9 4 2568 | 28 3 56 | 68 7 1 | |--------------------+-------------------+---------------------| | 456 8 256 | 3 7 9 | 1 26 246 | | 37 39 1 | 4 6 2 | 5 89 789 | | 467 29 26 | 5 1 8 | 47 3 24679 | |--------------------+-------------------+---------------------| | 2 6 3 | 78 9 45 | 47 1 4578 | | 8 5 9 | 267 24 1 | 3 26 2467 | | 1 7 4 | 268 258 3 | 68 589 25689 | *--------------------------------------------------------------*

[r2c5]=8=[r2c8]=5=[r9c8]-5-[r7c9]=5=[r7c6]=4=[r2c6]-4-[r2c5], solving the puzzle.

Carcul

by **ronk** » Fri Jan 05, 2007 1:29 pm

Carcul wrote:[r1c8]-6-[r1c1]=6|7=[r1c3]-7-[r2c23]=7|6=[r2c9]-6-[r1c8], => r1c8<>6

For those who like less cryptic expressions, here is one that specifies all the cells of the ALSs:

r1c8-6-{ALS:r1c14=6|7=r1c3}-7-{ALS:[r2c23,r2c4]=7|6=r2c9}-6-r1c8, => r1c8<>6

by **Carcul** » Sat Jan 06, 2007 1:22 pm

Wapati wrote:Another swordfish. There are two, one of them "required". Several Turbots, all three types available. (Sky, kite, classic.)

Code: Select all: *-------------------------------------------------------------* | 4 1367 137 | 8 379 367 | 569 13569 2 | | 3678 13678 2 | 379 5 367 | 69 4 1689 | | 368 9 5 | 1 2 4 | 7 36 68 | |--------------------+-------------------+--------------------| | 2 137 6 | 3457 8 137 | 459 159 179 | | 37 5 1347 | 2 347 9 | 46 8 167 | | 789 178 1479 | 457 6 17 | 2 15 3 | |--------------------+-------------------+--------------------| | 369 2 8 | 369 39 5 | 1 7 4 | | 5 4 79 | 679 1 8 | 3 2 69 | | 1 367 379 | 34679 3479 2 | 8 69 5 | *-------------------------------------------------------------*

[r9c5]=7|4=[r5c3]=1=[r5c9](=6=[r5c7]-6-[r2c7]-9-[r2c4]=9=[r1c5])-1-
-[r2c9]=1=[r1c8]-1-[r1c3]=1=[r6c3]-1-[r6c6]-7-[r5c5]=7=[r9c5], => r9c5=7 and the puzzle is solved.

Carcul

by **Carcul** » Sat Jan 06, 2007 1:47 pm

Wapati wrote:Swordfish day? Is that like "pancake day".
Swordfish, x-wing, xy-wing and a kite/Turbot.

Code: Select all: *----------------------------------------------* | 5 239 7 | 6 8 34 | 1 39 24 | | 4 239 8 | 59 1 7 | 6 39 25 | | 6 1 39 | 245 39 24 | 45 8 7 | |---------------+---------------+--------------| | 2 78 34 | 48 5 9 | 347 1 6 | | 9 35 345 | 1 7 6 | 234 24 8 | | 1 78 6 | 3 2 48 | 457 45 9 | |---------------+---------------+--------------| | 7 4 59 | 289 39 238 | 25 6 1 | | 3 59 2 | 79 6 1 | 8 457 45 | | 8 6 1 | 27 4 5 | 9 27 3 | *----------------------------------------------*

[r4c2]-7-[r4c7]=7=[r6c7]-7-[r6c2]-8-[r6c6]=8=[r4c4]=4=[r3c4]=5=
=[r3c7]-5-[r7c7](-2-[r5c7])=5=[r7c3]-5-[r5c3], => r4c2<>7 solving the puzzle.

Carcul

by **claudiarabia** » Sat Jan 06, 2007 9:52 pm

wapati wrote:Thanks Ravel, for the UL explanation!

Here is some xy practice. There are 5 followed by a sky/Turbot.

Code: Select all
. . .|. . .|9 4 . . . 7|9 . .|2 . 3 . 4 .|. 3 .|. 7 1 -----+-----+----- . 8 .|3 7 .|. . . . . 1|4 . 2|5 . . . . .|. 1 8|. 3 . -----+-----+----- 2 6 .|. 9 .|. 1 . 8 . 9|. . 1|3 . . . 7 4|. . .|. . .

modifying a puzzle of JPF I found this nice Unique Loop Type 3, not very difficult. If it wouldn't have a Swordfish too it would even fit the Zoo-Collection of Mike Barker.

Code: Select all: . 2 3 . 6 . . . 8 4 . . . . 8 . 9 . 7 . 9 . . 1 6 . . . . . 2 . . 1 . . 8 . . . . 3 . . 6 . 6 1 . 7 . . . . . . . 1 . . 9 . 3 . 3 . . . . . . . 6 . . . 8 . 7 . 2

Code: Select all: *-----------------------------------------------------------* | 15 2 3 | 4579 6 459 | 45 17 8 | | 4 15 6 | 57 #23 8 | #23 9 17 | | 7 8 9 | 45 #23 1 | 6 #23 45 | |-------------------+-------------------+-------------------| | 3 457 457 | 2 459 6 | 1 8 4579 | | 8 4579 2457 | 459 1 3 | 245 2457 6 | | 259 6 1 | 8 7 45 |#23+45#23+45 459 | |-------------------+-------------------+-------------------| | 25 457 8 | 1 45 27 | 9 6 3 | | 19 3 27 | 6 459 27 | 8 145 145 | | 6 19 45 | 3 8 459 | 7 145 2 | *-----------------------------------------------------------*

r2r3c5, r2c7,r3c8, r6c78 form a Unique Loop upon the Numbers 23. One of the two cells r6c78 have to renounce to the 2and3. The other cell of the two forms a naked pair with a cell in the same line, with r6c1 which contains the value 2 too.

The clou: if you omit 9 in r7c7 you get according to the Explainer a puzzle with Unique Loop Type 4 and BUG Type 1!

Enjoy

Claudia

by **wapati** » Sat Jan 06, 2007 10:56 pm

claudiarabia wrote:modifying a puzzle of JPF I found this nice Unique Loop Type 3, not very difficult. If it wouldn't have a Swordfish too it would even fit the Zoo-Collection of Mike Barker.

The clou: if you omit 9 in r7c7 you get according to the Explainer a puzzle with Unique Loop Type 4 and BUG Type 1!

Enjoy

Claudia

Thanks for the UL help Claudia!

I modded it a bit more and returned symmetry.
This can be solved with 3 skyscrapers. It still has the features Claudia mentioned if you chose to solve it with other patterns.

Code: Select all: . 2 3 . 6 . . . 8 4 . . . . 8 . 9 . 7 . . . . 1 6 . . . . . 2 . . 1 . . 8 . . . . 3 . . 6 . 6 1 . 7 . . . . . . 8 1 . . . . 3 . 3 . . . . . . . 6 . . . 8 . 7 . 2

by **wapati** » Sun Jan 07, 2007 5:48 am

This one has many patterns, as usual.

I give you no hints, there are a lot of paths.

Code: Select all: 9 . . | 6 . 7 | 8 5 . . . 8 | . . . | . . 9 . 5 . | . 2 . | . . 7 --------------------- 7 . . | . 9 . | . . 3 . . 9 | 4 . 6 | 2 . . 4 . . | . 7 . | . . 6 --------------------- 1 . . | . 6 . | . 2 . 5 . . | . . . | 6 . . . 2 6 | 5 . 3 | . . 4

by **wapati** » Sun Jan 07, 2007 6:06 am

I usually solve (pencil, paper) puzzles before I post them.

This "UFO" I will post before...

It is a tad busy, pattern wise.

Code: Select all: 3 . . | . . . | . . . . 2 . | . 4 9 | 3 . . . . 8 | 2 . . | . 7 . --------------------- . . 3 | . 8 . | . 9 . . 1 . | 4 . 3 | . 2 . . 6 . | . 2 . | 8 . . --------------------- . 4 . | . . 7 | 9 . . . . 6 | 9 5 . | . 8 . . . . | . . . | . . 1

by **wapati** » Sun Jan 07, 2007 8:10 am

Thanks again daj, so many patterns!

This here is a whack of odditty.

Code: Select all: . . . | . . 3 | 6 . 5 . . 8 | 6 . . | . 1 . . 1 . | . 5 . | 7 . 4 --------------------- . 4 . | . 3 . | . . 1 . . 9 | 4 . 1 | 8 . . 1 . . | . 8 . | . 9 . --------------------- 4 . 2 | . 9 . | . 5 . . 7 . | . . 4 | 9 . . 9 . 1 | 8 . . | . . .

by **StrmCkr** » Sun Jan 07, 2007 9:05 am

intresting puzzle

i solve it with 2
yielding chains type 1:

Code: Select all: . . . | . . 3 | 6 . 5 . . 8 | 6 . . | . 1 . . 1 . | . 5 . | 7 . 4 --------------------- . 4 . | . 3 . | . . 1 . . 9 | 4 . 1 | 8 . . 1 . . | . 8 . | . 9 . --------------------- 4 . 2 | . 9 . | . 5 . . 7 . | . . 4 | 9 . . 9 . 1 | 8 . . | . . .

befor i apply any simple sudoku reductions i spot at

row 5 forms a Conjugated als (124) allowing me to use a yield chain type 1:

here
r1c5[124]
R8c5[12]
R2c5[124]

which removes 2 from
R5c5,R9c5

(then remove all hidden/box/line reductions ect to lead me to the next one)

yield chain type 1:
found on row 2
Conjugated als {257}
R2C1[257]
R2c2[25]
R2c6[72]

removes 2 from
R2c7
puzzle solves as singles.

(but people still don't understand these so oh well...just figured id chime in on it anyway...)
(probably should re work my confusing explinations down to minimual language and more clear examples on easier puzzles then hopefully that clears things up a bit)

nice puzzle lots of other options on it.

The New Sudoku Players' Forum

CHAINS, not required. Good puzzles.

Unique Loop type 3

Re: Unique Loop type 3