The New Sudoku Players' Forum

by **fermat** » Wed Jun 21, 2006 11:53 am

Here is one that requires a Turbot Fish.

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

by **tso** » Wed Jun 21, 2006 5:50 pm

I'm not clear on the concept. Does this one (previously posted in another thread) fit the theme:

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

All singles, then either BUG or a 5 cell XY-chain.

by RW » Thu Jun 22, 2006 8:22 am

I'm afraid most of the techniques based on strong links (skyscraper, turbot fish etc.) can also be done by coloring or multiple colors, which is against the initial rules. Therefore none of fermats puzzle passed the test. If you wish to test them easily yourself, just copypaste into SS and hold down <F11>. If the program gives you "no hint available" and there is no obvious UR-reductions at that point it might pass. As ronk already pointed out, gsf's puzzle could be solved with x-wing and xy-wing. Tso's puzzle would qualify, I'll add it to the list.

RW

by **gsf** » Thu Jun 22, 2006 4:24 pm

this one solves in 11 steps
the 6th is a length 9 xy-cycle

Code: Select all: [17]7[97]9[89]3[82]9[92]2[93]4[73]7[23]8[28]7[17]7

the rest are singles

Code: Select all: # effortless extreme VII 11 steps 26 clues diagonal symmetric minimal 5 . . 6 . . . . . 9 4 . 2 . . 3 . . . 6 . 7 . 8 . 4 . 3 . 9 . . . 8 . . 4 . . . . . . . . . . 6 . . . 1 3 2 . . . 9 . 5 . . . . . . . . . 2 1 . . . . . 3 6 . 5 7

by RW » Thu Jun 22, 2006 6:39 pm

gsf wrote:this one solves in 11 steps
the 6th is a length 9 xy-cycle

Code: Select all: *--------------------------------------------------* | 5 178 178 | 6 4 3 | 79 2 89 | | 9 4 78 | 2 5 1 | 3 *678 *68 | | 2 6 3 | 7 9 8 | 5 4 1 | |----------------+----------------+----------------| | 3 12 9 | 5 16 27 | 8 67 4 | | 4 128 128 | 3 16 27 | 67 9 5 | | 7 5 6 | 4 8 9 | 1 3 2 | |----------------+----------------+----------------| | 1 37 47 | 9 2 5 | 46 *68 -368 | | 6 39 5 | 8 7 4 | 2 1 39 | | 8 29 24 | 1 3 6 | 49 5 7 | *--------------------------------------------------*

Sorry, the UR in r27c89 eliminates candidates 6 and 8 from r7c9 to solve the puzzle... But keep on making those puzzles!

RW

by **gsf** » Thu Jun 22, 2006 7:20 pm

I'm confused

RW wrote:Sorry, the UR in r27c89 eliminates candidates 6 and 8 from r7c9 to solve the puzzle... But keep on making those puzzles!

from the first message wrote:[edit: I decided to count Uniqueness rectangles as an "advanced technique"]

btw, the xy-cycle makes the same elimination

by RW » Thu Jun 22, 2006 9:01 pm

gsf wrote:I'm confused

I've tried to classify the puzzles by technique, even though I know it's impossible to make a puzzle that requires a certain technique. As I decided to count URs as an "advanced technique" I started keeping a separate list of puzzles that could be solved with URs.

I also wrote:I wouldn't let a puzzle that can be solved with an uniqueness rectangle on the list under any other technique.

I think your puzzle is a lot easier to solve with the UR, that's why I wouldn't classify it as a puzzle that requires a length 9 xy-cycle as you suggested.

The problem with adding it to the UR category is that I'm not quite sure if I can count the UR as one advanced step. The two candidates are eliminated by two different kinds of patterns, even though they happen to be eliminated from the same cell by a rectangle in the same four cells. Candidate '6' is eliminated by what Mike Barker classifies as a "UR+2D/1SL" here. Candidate '8' doesn't have the strong link and is eliminated by the pattern I've described here. It is very possible that someone sees the first elimination and not the second, therefore it doesn't fulfill the requirement of one advanced move. It's a tricky situation and I'll have to think about it for a while.

RW

by **gsf** » Thu Jun 22, 2006 10:57 pm

RW wrote:
gsf wrote:I'm confused

I've tried to classify the puzzles by technique, even though I know it's impossible to make a puzzle that requires a certain technique. As I decided to count URs as an "advanced technique" I started keeping a separate list of puzzles that could be solved with URs.

so you don't want to see UR solvable puzzles in this thread?

by **ronk** » Fri Jun 23, 2006 12:23 pm

RW wrote:The two candidates are eliminated by two different kinds of patterns, even though they happen to be eliminated from the same cell by a rectangle in the same four cells.

Code: Select all: 5 178 178 | 6 4 3 | 79 2 89 9 4 78 | 2 5 1 | 3 *678 *68 2 6 3 | 7 9 8 | 5 4 1 -------------+-------------+------------- 3 12 9 | 5 16 27 | 8 67 4 4 128 128 | 3 16 27 | 67 9 5 7 5 6 | 4 8 9 | 1 3 2 -------------+-------------+------------- 1 37 47 | 9 2 5 | 46 *68 *368 6 39 5 | 8 7 4 | 2 1 39 8 29 24 | 1 3 6 | 49 5 7

At Simple Sudoku's sticking point, the {68} uniqueness rectangle in r27c89 has four strong links, two for digit 6 in r2 & c9, and two for digit 8 in r7 & c8. I view the exclusions r2c8<>6,8 and r7c9<>6,8 as four applications of the "UR+2D/1SL" technique in a "single step".

by RW » Sat Jun 24, 2006 8:43 am

gsf, in the original post there are UR-solvable puzzles in their own category. Sorry if a bad choice of terminology confused you.

Ronk, you're right, I missed the strong linnks in the columns. I'm not very used to look for SLs as such. I'll add the puzzle in the UR category.

RW

by **pyrpoliser** » Sat Jun 24, 2006 1:48 pm

Edited

by **Mike Barker** » Sun Jun 25, 2006 4:55 am

Here are a bunch ranging from the basic to the esoteric which I hope fit the bill, have the number of nodes in an XY-chain correct, and balance UR's and XY-chains. The numbers in the front are my method of keeping track of the technique and can be ignored.

Code: Select all: 11 Finned Swordfish ....2.6.8.......15.57....4..........6.8.4.....32..79...9.2..37.....18...36....... ..8..7964..96...........7.......1.3.7..2.41...6.5.........5....5....2.83.463....7 11 Franken Swordfish 1........79.....4.....37...51.4..7.9...38.......1..8......2...3.75.......6...4.5. 8...5..41......5...4.....6345.1......3.7.......12..6.512.3..4........7....3.9..2. 12 Franken Jellyfish ......5..87.5.4.9..3..9.....6..5...9.8....746.........4.1....2....4..1.7...8..... 12 Franken Jellyfish (2 per puzzle) ..1...9......2...54.81.9.7..1..63..8..7.......3..1....2..7..15....6..82.3........ ..5......94..7.....165.9..4....9...8.....7..21.3...67...7..4..639.......6..1.5... 18 Two strong links (Turbot Fish) 6...3.2..3..71..8...7..23.1...4......416.....82....1..4......5.1...739........6.. 19 Three strong links (Turbot Chain) 1........746.....2...3..65.971..2.....2....16.....4.......8..2..9...13..58..4.... > ...64.5..54...3.8......7......89....1...6..3..97...6..9.5.......3..5.1.9......7.. 22 XYZ-wing ..1....5.....85.74..39..8..5..7.81...8..6...5...4...2..........6.7.4......5..9..3 ...8..6...1.9..82...56..3...52.....38....4.1.....5.2..2.....1....64.....5...27..4 23 WXYZ-wing .2.13.9.795......4......1..18..7....3.....476...36.2......8..6.5...1.....4......3 .7......9....4.1.61.....28...36.......8423...5.6..8...3.....8...4..8.69....5....1 24 VWXYZ-wing .8.5.......1......9..1.45..7.2..316.....1.7.5.....93.4........6...8..9...147..... .......6..93.8......6.49......37....182...7.........1..1..538........67.36..981.. 25 UVWYXZ-wing .4..9...76.85....2..5....8....2..7..41..36........1.3.2..3...1.9...4.........9.2. .9......4..78.....4..7.21.8..9.5.....6....54..7...1.6..51.....39..1.8.5....5..2.6 26 TUVWXYZ-wing 2.....93...57..........3..41..2....5.4....61...7........3..426..68.2...........9. 27 4-node XY-ring .13.....4...61...2.2....8..4...5...1..5.4.23.6.....5.9..1.28....9.4........9...7. ........4...8..7...76....151....2.56.2.93....4..........9...4.72...6.3......1.... 28 5-node XY-chain 3.2.6.7..1.4..7.2...5....3.4..3....5......2.......9..8.....28...56..4...7...5.1.. 30 6-node XY-chain .1.2...4..9.....3.5..4................75..1.8..68.1...3...2.8......6..2.85..4...3 .6..98.4.31.......5.8....3...1..6.........4.....1825.....245..7...9..6.1..7...2.. 32 7-node XY-chain .9..8..7....3...5265.4.....8.7..31.61........9..8.4.......6.4.778..........2..... 9-node XY-chain ....126.7.59....32.......8.7..........84...7...58.912..9.7582....6.4...5.4....... 33 ALS xz-rule 9..2...8.24.........8.4...9......3.8.......7....591...6...7.......8..6...71..6.54 .7.5.....4..19....51.....9..43.2..1...8....26.2.3....5.......8....7...5179......2 35 UR+1 (Type 1) ..32.....4...........8.7..5...675...95.4..7..8.1.3..6.....96.7...7...8...9......2 .47.........9....698...5.72..5.7..6.3.4......27.5............9.....16..7.62..84.. 36 UR+2x (Type 2) ...9.7..8....6....72.5...9..83...6....2....3.4....37...9....14..1...2..6....56... 896.4..........7.2...9...6..18..9.246..3...8..3..1.......4..2..3....6.....5.3..1. 38 UR+2X (Type 3/3B) (8-node XY-chain) ............3..6......742...34.5.9.2.7.4..5.1.........8.5.16..36..........7.9...8 38 UR+2X (Type 3/3B) .7...342.9.2........4..765...697...8...1.5.....76........2.8.94....5...7......2.. 39 UR+2rd ...4.3.7.53..............469........8....74.2...36..1..7.18..6..5..2.....4...57.. 8..3....19.2.........56...4..8..4.65...7....32.6..........1........8.5427........ 40 UR+2kx .2...8.....5...2..7...1...6.......2.938.2......74.58.....1.97....95..6..6...83..4 41 UR+4X/1SL (Type 4) .....2..4..17..8...4..6..3.4.6.....53.7....8......9.....9.18..21......5..5...476. 42 UR+3N/2SL .....49.623.7........5....11.........4....8...5...36.99....8......1..3.7..2..9.4. 42 UR+3C/2SL (8-node XY-chain) 2.1.....8.....3..........626.3..7....52.947..7..3..1..4....6.519..5...4...7.1.... 42 UR+3C/2SL .....15...453.........9.468..8..3..99..2.7.......5..266......4142.........9.....3 50 BUG+1 (8-node XY-chain) ..8...2..9.......72.7....934...9...6....2.........31.5.....8....5.43.....6...7.84 +-------------+--------------+-------------+ | 5 34 8 | 39 7 49 | 2 6 1 | | 9 13 6 | 23 48 12 | 48 5 7 | | 2 14 7 | 18 *56 *56 | 48 9 3 | +-------------+--------------+-------------+ | 4 28 35 | 18 9 15 | 7 23 6 | | 1 7 35 | *56 2 -456 | 9 34 8 | | 6 289 29 | 7 48 3 | 1 24 5 | +-------------+--------------+-------------+ | 7 29 4 | *56 *56 8 | 3 1 29 | | 8 5 1 | 4 3 29 | 6 7 29 | | 3 6 29 | 29 1 7 | 5 8 4 | +-------------+--------------+-------------+ 51 BUG+x (Type 2/2B) 3.....4.........8..9..4.1.........7...8..6.....4.796...7.9.83...4.32....25...1... +-------------+------------+--------------+ | 3 8 *256 | 7 1 *25 | 4 -256 9 | | 4 1 *25 | 6 9 3 | 7 8 *25 | | -56 9 7 | 8 4 *25 | 1 3 *256 | +-------------+------------+--------------+ | 9 6 15 | 15 8 4 | 2 7 3 | | 7 2 8 | 15 3 6 | 9 145 145 | | 15 3 4 | 2 7 9 | 6 15 8 | +-------------+------------+--------------+ | 16 7 16 | 9 5 8 | 3 24 24 | | 8 4 9 | 3 2 7 | 5 16 16 | | 2 5 3 | 4 6 1 | 8 9 7 | +-------------+------------+--------------+ 50 Advanced BUG-Light Elimination 3...1..59..762....1...4.......97...5..4....7..6....2.4.7......1..5..8.3..91...... +-------------+---------------+---------------+ | 3 4 2 | 8 1 7 | 6 5 9 | | 9 58 7 | 6 2 35 | 14 14 38 | | 1 58 6 | 35 4 9 | 378 28 27 | +-------------+---------------+---------------+ | 2 13 8 | 9 7 4 | 13 6 5 | | 5 13 4 | 2 68 16 | 9 7 38 | | 7 6 9 | 35 358 135 | 2 18 4 | +-------------+---------------+---------------+ | *68 7 3 | 4 *56 2 | *58 9 1 | | 46 2 5 | 1 9 8 | 47 3 67 | | *468 9 1 | 7 -356 356 | *458 248 26 | +-------------+---------------+---------------+ (r9c5-5-r7c5, r7c5-8-r7c7, r7c7-6-r7c1, SL:r7c7=5=r9c7, SL:r7c1=8=r9c1): r79c15|r79c7 => r9c5<>6 52 Nice Loop: r4c4=6=r7c4=3=r7c6=9=r4c6~9~r4c4 => r4c4<>9 .....73...9...........16.583.....1..72.1...9........26.14.8.27....2.5.....97..... +------------------+--------------------+--------------------+ | 1568 568 568 | 4589 259 7 | 3 146 1249 | | 1568 9 37 | 3458 235 2348 | 467 146 1247 | | 4 37 2 | 39 1 6 | 79 5 8 | +------------------+--------------------+--------------------+ | 3 4568 568 |-45689 25679 *2489 | 1 48 457 | | 7 2 568 | 1 56 48 | 458 9 3 | | 9 458 1 | 3458 357 348 | 4578 2 6 | +------------------+--------------------+--------------------+ | 56 1 4 | *369 8 *39 | 2 7 59 | | 68 3678 37 | 2 469 5 | 4689 13468 149 | | 2 3568 9 | 7 46 1 | 4568 3468 45 | +------------------+--------------------+--------------------+ 52 Nice Loop: r4c7=1=r4c8-1-r9c8=1=r9c3=4=r4c3~4~r4c7 => r4c7<>4 .63.4...1.........129...8......38....17.....8..8...6....21..9..8..42..3.5....37.. +-----------------+----------------------+---------------------+ | 7 6 3 | 8 4 259 | 25 259 1 | | 4 8 5 | 23679 1679 12679 | 23 2679 23679 | | 1 2 9 | 3567 567 567 | 8 4567 34567 | +-----------------+----------------------+---------------------+ | 269 45 *46 | 25679 3 8 | -1245 *12579 2579 | | 2369 1 7 | 2569 569 24569 | 2345 259 8 | | 239 345 8 | 2579 1579 124579 | 6 2579 23579 | +-----------------+----------------------+---------------------+ | 36 347 2 | 1 5678 567 | 9 468 46 | | 8 79 16 | 4 2 79 | 15 3 56 | | 5 49 *146 | 69 689 3 | 7 *12468 246 | +-----------------+----------------------+---------------------+ 53 Nice Loop: r3c2=1=r6c2=7=r4c2-7-r4c9-6-r4c7=6=r3c7~6~r3c2 => r3c7<>1 6..1......5....9..7.3.....43..8...1..8.6..59...6...2...4...18......6.7.5..9..5... +------------------+-----------------------+----------------+ | 6 29 248 | 1 245789 24789 | 3 2578 278 | | 1248 5 1248 | 2347 23478 234678 | 9 278 16 | | 7 *129 3 | 259 2589 2689 | -16 258 4 | +------------------+-----------------------+----------------+ | 3 *27 5 | 8 2479 2479 | *46 1 *67 | | 124 8 124 | 6 1237 237 | 5 9 37 | | 9 *17 6 | 3457 13457 347 | 2 3478 378 | +------------------+-----------------------+----------------+ | 5 4 7 | 23 23 1 | 8 6 9 | | 128 3 128 | 49 6 489 | 7 24 5 | | 28 6 9 | 47 478 5 | 14 234 123 | +------------------+-----------------------+----------------+ 53 Nice Loop: r1c1=2=r1c9=1=r3c9-1-r3c5-7-r2c5=7=r2c3~7~r1c1 => r2c3<>2 .69.3..8..1..........2...9..91.4..2.7.....4...2...9..7...7..91...3.5.........2..6 +---------------------+------------------+-------------------+ | *245 6 9 | 145 3 145 | 7 8 *1245 | | 23458 1 -24578| 69 *79 4568 | 2356 3456 2345 | | 3458 34578 4578 | 2 *17 14568 | 356 9 *1345 | +---------------------+------------------+-------------------+ | 356 9 1 | 35 4 7 | 3568 2 358 | | 7 358 568 | 1358 2 135 | 4 356 9 | | 3458 2 458 | 358 6 9 | 1 35 7 | +---------------------+------------------+-------------------+ | 26 45 26 | 7 8 34 | 9 1 345 | | 19 478 3 | 69 5 16 | 28 47 248 | | 19 4578 4578 | 34 19 2 | 358 3457 6 | +---------------------+------------------+-------------------+ 58 ALS xz-rule (A=3 cells) 7..3...6.....1...4.3...52......649..9.61........8.......3.2..5.2......1..154...7.

by RW » Sun Jun 25, 2006 10:50 am

Thank you Mike for the puzzles. I'll check them as soon as possible, but it may take some time until I find the required spare time.

RW

by **daj95376** » Sun Jun 25, 2006 4:23 pm

Mike Barker, A great collection.

FYI: In the following example, it should be noted that a Franken Swordfish isn't needed to solve the puzzle -- just Singles, a Pair, and an XY-Wing. (Or else I need to rewrite my XY-Wing logic!)

8...5..41......5...4.....6345.1......3.7.......12..6.512.3..4........7....3.9..2.

by **Mike Barker** » Sun Jun 25, 2006 8:29 pm

Daj - you are right, my solver normally uses XY-wings after fish. I've moved XY-wings up in the technqiues order. Here's a replacement and a few more as well. I threw in some X-wings and XY-wings as well - may as well have as close to a complete set a possible.

Code: Select all: 9 Finned X-wing 6..........7...64.....92.1...4..79...3..1.42.......1.6..32....5.4.5......2....... Row 1..5.9....4.....788..3..9..7..8..4......6.1...62.7..3.4...5......7...35....1...8. Row 10 Finned Swordfish ......6....569..7..2....5..3.9.....4....2.1.....4.7.....391..5..4..7...2..1..3.4. 11 Franken Swordfish ..8..7964..96...........7.......1.3.7..2.41...6.5.........5....5....2.83.463....7 10 Franken Swordfish (2 per puzzle) ...3..9.2..7..5..44...9..8....5.3798...........671....7..9..8.5.......2...52...4. 11 Franken Jellyfish .1..3.......29.5.17.....49.4..3.1..6........4.3.9..72...9.6.8..5..4.........1.2.. 19 Three Grouped Strong Links (Grouped Turbot Chain) 1.8.9.....6.......52.4....1.......14...9...8...3..6.9..816.2.......7..6.49..5...2 21 XY-wing ...82....7.34.6...5.......79......5..3.5....4...2.4.....9...38.26..7......4..12.. .......5.6.....91.4....9...2..8.16..3.1.6....8..5......2.....87.3..9.52....34.... 46 UR+3N/2SL (8-node XY-chain) ........72..........379..1.4.6...25.....5........76..385.9.7....4....8.6...4.8.2.

The New Sudoku Players' Forum

The Effortless Extremes thread