The New Sudoku Players' Forum

[Hajime]

Found in NRC dutch newspaper a S-Doku, Saturday 20-mar-2021.

A normal Sudoku but with stacks and bands for the blue cells.
A band is 3 boxes horizontal. A stack is 3 boxes vertical.
So 6 extra regions/houses. Pure Singles Only.

Some extra puzzles generated with SiSeSuSo:
Pure Singles only & Symmetric: ...4.8...89.....61..................58.6.7.94..................76.....43...1.3...
Singles Only (Generalized): .......3....3.1........4..9......7.5..8.......3........5..6.........8............
A SkyScraper and a XY-wing: ...3.........7....7.5.6..8..98.......1..45............................3..........
Some SkyScrapers needed: ....9..........976..........8.1.4.5..316....9..........2.9.......................

[urhegyi]

The one published in the NRC newspaper wasn't hard at all.

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912863754846527319573149826794356182368912547251784693425631978137298465689475231


[Hajime]

The one published in the NRC newspaper wasn't hard at all.

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912863754846527319573149826794356182368912547251784693425631978137298465689475231


By pencil and paper?

[urhegyi]

The one published in the NRC newspaper wasn't hard at all.

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912863754846527319573149826794356182368912547251784693425631978137298465689475231


By pencil and paper?

Yes, with full pencilmarks.
The symmetrical form of your singles only example was a quick solve too:

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612458739894372561357961428423519687581627394976834215138746952769285143245193876


[Hajime]

Nice job. The other 3 are increasing difficult. And you need a trick to paste them in SiSeSuSo.

[urhegyi]

Nice job. The other 3 are increasing difficult. And you need a trick to paste them in SiSeSuSo.

Your generalized(locked) singles example was quit hard.

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475896132829351674316724859142639785698475321537182946253967418761548293984213567


[urhegyi]

I have been able to solve your skyscraper / xy-wing example:

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149382567863579214725164389398216475612745893457938126971853642586427931234691758


and your multiple skyscrapers one too.

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765398142348251976219746538987124653431675829652839714123987465874563291596412387


[Hajime]

I have been able to solve your skyscraper / xy-wing example:

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149382567863579214725164389398216475612745893457938126971853642586427931234691758


I could not solve this by P&P.
To load the puzzle into SiSeSuSo, the trick is to define 2 fully overlapping Sudoku's.
One with the bands and one with the stacks as Jigsaw pieces 1 to 3.
The givens are identical, of course.

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#2//B4,JSB/B4,JSB
.....................45.......7..146....2......8........1.9...3.....6...........8
..11111...1.....111........2.........2222222.........2........333.....3...33333..
.....................45.......7..146....2......8........1.9...3.....6...........8
..12223...1.....331........1.........1122233.........3........311.....3...12223..


And you need to adapt some colors: O (overlap)=white, Jigsaw J1,J2,J3 = Light Blue

It is difficult to generate more difficult ones.
..........5.1.........9........3..4..8.......4.1.........2...........9.....9..17.
Needs also a XY-chain of length 6.

[urhegyi]

Creating difficult ones isn't easy at all(an attempt):

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#2//B4,JSB/B4,JSB
....9.......1.5.....5...1...7.....5...........5.....4...6...8.....2.7.......8....
..11111...1.....111........2.........2222222.........2........333.....3...33333..
....9.......1.5.....5...1...7.....5...........5.....4...6...8.....2.7.......8....
..12223...1.....331........1.........1122233.........3........311.....3...12223..

[Hajime]

Very nice one, urhegyi

[1to9only]

Creating difficult ones isn't easy at all(an attempt):

Here are a few, one of each ED rating:

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............4....7........5.....27....97.36....75.....5........7....8............ 14 ED=10.1/1.5/1.5
...........16........2...........97...........84...........7........32........... 10 ED=9.9/9.9/2.8
..............7...........52..9..8......6......9..3..41...........5.............. 11 ED=9.8/1.5/1.5
....3..............5.7.........2..6...........7..6.........8.1..............9.... 10 ED=9.7/9.7/2.8
.....3........................3..2.5..8.6.1..7.9..1........................8..... 11 ED=9.6/2.3/2.3
...2.................7.......6.8..9...5.6.2...7..4.6.......3.................1... 13 ED=9.5/9.5/2.6
....6.......4.........9.6.2........9.........1........5.4.2.........7.......3.... 12 ED=9.4/7.8/2.8
.....7.....7.......8..63..........3...........1..........58..2.......9.....9..... 12 ED=9.3/9.3/2.6
.........2..3....1.4...1......9..8.............8..6......5...4.7....2..6......... 14 ED=9.2/9.2/2.6
...5......92..................68.....8.7.4.6.....35..................17......3... 14 ED=9.1/9.1/2.6
.........7.8.........2.6......7.4..2.........1..5.8......3.1.........4.6......... 14 ED=9.0/9.0/2.8
..4.7...6...............7.......1..5...4.5...3..2.......1...............4...1.8.. 14 ED=8.9/8.9/2.8
.4.6.......75.........3......2..9...............3..2......2.........19.......3.7. 14 ED=8.8/8.8/2.6
....3.....1..94...............3..78.....1.....57..2...............82..1.....6.... 15 ED=8.7/1.5/1.5
2..5..46......1...............7..2.............7..3...............6......59..2..7 14 ED=8.6/8.5/2.6
.3.1.....9...........3.......74........7.2........17.......6...........5.....5.6. 14 ED=8.5/8.5/2.8
..52.6......1....................48.....7.....93....................8......5.16.. 13 ED=8.4/8.2/2.6
....1....4..8...7........45.............2.............96........1...3..9....7.... 13 ED=8.3/8.3/2.6
...3.7........1..8......3........6...9.....2...1........5......4..7........5.9... 14 ED=8.2/2.9/2.6
.4........17...........1......2..3......8......3..6......5...........45........6. 13 ED=8.1/2.8/2.6
............6..........9.81...12.................74...59.3..........8............ 12 ED=8.0/2.9/2.8
......6..3...............3....5.9.4....8.6....1.2.3....9...............7..8...... 14 ED=7.9/2.9/2.6
....49...............5.38.2..53...................15..1.37.2...............13.... 16 ED=7.8/7.8/2.6
..64........2...8.......7........19...........25........8.......4...1........86.. 14 ED=7.7/7.7/2.6
.........9..2.......1....8..5.6...................1.9..7....5.......9..3......... 12 ED=7.6/2.9/2.8
........1..........5...3......7...4.6...5...2.3...9......8...3..........7........ 13 ED=7.5/1.5/1.5
.....8..........4...1.46.....4.1..5...........7..3.4.....69.7...4..........3..... 16 ED=7.4/1.2/1.2
....3......25...........7....9...4...1.4.9.7...8...9....6...........46......6.... 16 ED=7.3/2.9/2.8
...9..3.....3........8.....6.4.....................9.2.....5........7.....2..4... 12 ED=7.2/1.5/1.5
.1.........37.....7..........5..6..2.........2..1..5..........8.....96.........4. 14 ED=7.1/3.2/2.6
.....4.......3.6.............1....4...21.89...7....1.............3.6.......9..... 14 ED=7.0/1.5/1.5
4...6.83..9...3......9..................5..................1......6...7..64.3...1 15 ED=6.9/1.2/1.2
......3...1.6..........4..9..9..8...............7..2..4..9..........1.7...8...... 14 ED=6.8/2.8/2.6
...5.....3....2...2..4.1.6........7...........9........7.8.9..6...3....1.....4... 16 ED=6.7/6.7/2.6
....6.8...............2.......4..7....5...9....3..9.......7...............6.5.... 12 ED=6.6/2.9/2.6
.6..3...4....9....1.............8.....2...3.....3.............1....5....9...4..8. 14 ED=6.5/1.5/1.5
.9..3..............5.1..2......1.....6.7.4.8.....2......6..7.5..............8..7. 16 ED=6.2/1.5/1.5
....2...............7.81.3...8.........3.9.........6...1.26.5...............1.... 14 ED=5.7/2.6/2.6
..............1......2...45.....9....4.....3....8.....92...7......4.............. 12 ED=5.6/4.0/2.8
.1.........6..3....2.8.......8.9.................6.7.......2.5....6..9.........3. 14 ED=5.0/1.5/1.5
...7....5.....326....4..................8..................9....738.....9....4... 13 ED=4.6/1.2/1.2
..8.........3........1.....9......2..3.....7..5......4.....7........9.........9.. 12 ED=4.5/1.5/1.5
.2..15.....18........6...........6.4.........4.7...........9........18.....28..3. 16 ED=4.4/2.9/2.6
5...8.......7...1..4.5.....................................8.7..2...9.......6...2 12 ED=4.2/1.5/1.5
..3..7...6....5..............1....89....9....29....1..............8....3...5..6.. 15 ED=4.0/2.8/2.6
.6...7.........2......5..........8...7.398.5...4..........8......6.........5...9. 15 ED=3.8/1.2/1.2
.....6.......3.7...7.4..2........8.............2........1..8.3...3.5.......3..... 14 ED=3.6/2.9/2.6
.3.....6....9..8.........7......4...............7......7.........6..3....1.....5. 12 ED=3.4/2.8/2.8
.....61....6...................5..7..5.9.2.4..2..7...................7....18..... 14 ED=3.2/1.5/1.5
......91....4..7.........5......1.......2.......5......4.........1..6....23...... 13 ED=3.0/2.8/2.8
.2...7.....5.........9........51.....5.3.8.1.....74........6.........9.....1...8. 16 ED=2.9/2.9/2.8
.1..8....6...2.....9..........3...7...........4...8..........6.....4...5....1..2. 14 ED=2.8/2.8/2.6
.1..............8....7........9.......43.52.......7........4....5..............1. 12 ED=2.6/1.5/1.5
....75.......2.........3.........52...4...8...89.........1.........4.......69.... 14 ED=2.5/1.5/1.5
......7......3..8.5............14.....1...5.....26............3.4..2......9...... 14 ED=2.3/1.5/1.5
..3..7..2.....................2.5.....1.3.4.....6.1.....................9..5..6.. 13 ED=2.0/1.5/1.5
.2.....6...59.7.................92....9.8.7....25.................3.61...4.....2. 17 ED=1.9/1.5/1.5
........5....56..........7....3..6....4.9.5....1..5....7..........78....2........ 15 ED=1.7/1.5/1.5
.3..7..1..........6...........9......5..3..4......6...........9..........8..1..3. 13 ED=1.5/1.5/1.5



[Hajime]

Impressive 1to9only. What solver do you use to rate them?

.....4.......3.6.............1....4...21.89...7....1.............3.6.......9..... 14 ED=7.0/1.5/1.5

This one is solvable using WXYZ-wing with rating SER 5.5

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Eliminated candidates per Method and per Sudoku

Method   \  Sudoku |   SER |     1     2
                   |-------|------------
Not counted elims  |     0 |   103     6
Naked Singles      |   0.1 |     3     5
Hidden Singles     |   0.2 |   125     8
Naked Single  [1]  |   2.5 |     2     1
Naked Pair    [2]  |     3 |     4     0
Naked Triple  [3]  |   3.6 |     3     0
Naked Quad    [4]  |     5 |     6     0
Hidden Quad   [5]  |   5.4 |     8     0
Pointing/Claiming  |   2.8 |    36     8
Locked Singles[3]  |   2.9 |     5     8
Locked Singles[4]  |   3.4 |    18    12
WXYZ Wing     [4]  |   5.5 |     1     0
Turbot-fish   [4]  |   4.2 |     3     0
XY-Wing       [3]  |   4.1 |     0     1
                   |-------|------------
Eliminated Cand's  |   366 |   317    49
Sum(SER * Cand's)  |   416 | 320.9  95.1

Initial Candidates :   366
Maximum SER rating :   5.5 <- Approach
Labour rating      :   416 <- Experimental rating
Time needed        : 00:00:02.258
SiSeSuSo Solver and Generator (version 2021-03.b)

[creint]

Impressive 1to9only. What solver do you use to rate them?

.....4.......3.6.............1....4...21.89...7....1.............3.6.......9..... 14 ED=7.0/1.5/1.5

This one is solvable using WXYZ-wing with rating SER 5.5

Only 2 rounds of locked singles required if you use the hidden constraints.

[1to9only]

What solver do you use to rate them?

I am adding S-doku as a variant to my SukakuExplainer, so I'm using the SudokuExplainer generator and serate.
The github repo wont be updated for another week or so!

S-dokuX is also possible!

[urhegyi]

What solver do you use to rate them?

I am adding S-doku as a variant to my SukakuExplainer, so I'm using the SudokuExplainer generator and serate.
The github repo wont be updated for another week or so!

S-dokuX is also possible!

Code: Select all

#2/X/B4,JSB/B4,JSB
.6..9..8..............7......62.97.............75.36......6..............4..5..7.
..11111...1.....111........2.........2222222.........2........333.....3...33333..
.6..9..8..............7......62.97.............75.36......6..............4..5..7.
..12223...1.....331........1.........1122233.........3........311.....3...12223..