The New Sudoku Players' Forum

by **wapati** » Mon Oct 02, 2006 7:45 pm

This puzzle can be solved by all "solvers" that I tried but all took differnet (a lot different) paths. This may be the "hardest to rate" puzzle?

It is a great illustration of 'whatever path you take' works.

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

by **wapati** » Thu Oct 05, 2006 9:22 am

This fully symmetric puzzle is easy except for requiring UR1, UR4 and a Unique Closed Loop!

Code: Select all: 5.9.6.1.3 ......... 3..912..8 ..3.7.2.. 6.71.43.9 ..1.8.4.. 9..231..4 ......... 4.5.9.6.1

by **wapati** » Thu Oct 05, 2006 11:51 am

I wanted a Jelly for the effortless extremes but the only one I have generated needs an xyz. It is hard to avoid the Jelly, though forcing chains can avoid nearly any pattern, I guess?

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

by **daj95376** » Thu Oct 05, 2006 5:00 pm

I doubt if RW is accepting Jellyfish for the EE thread, but here's some examples that I believe will qualify. They definitely qualify for the Superior Plus thread.

Code: Select all: .......15.84.7..9..7.3..4..76.83.5...3.9.1.6...9.67.31..6..3.5..4..1.67.51....... .....13.8.1...8..2..2..3.4.......7.1.8..9..3.4.9.......2.7..8..1..2...6.6.48..... .....3..7.3.8.1..921...78........46...82.43...24........17...238..3.9.1.7..6..... ...9...1..9.14.683....6.7.......436.4...5...2.617.......3.9....159.72.3..7...6... ..2.4.....1.5.6.2...41....59.16..2..2...9...1..5..13.41....35...9.4.2.7.....1.6.. ..5.2.68....6........9.72...58....7..42.7.36..3....54...72.3........9....24.6.8.. ..789...5.4...6..9.597..8....4..1..7.8..2..1.9..4..2....5..418.4..6...7.1...784.. ..98.2.6...8.....123...9.....64.....7...3...2.....76.....2...736.....9...4.1.38.. .3.5....98.93....5..4...16...14.....3..261..4.....86...13...9..6....24.84....3.5. .4..28.7187.6...2............48..26...1.4.9...86..24............6...9.4313.27..9. .5.6.98...3...7..9....4.51.8......4...3.1.7...9......6.84.7....1..9...3...94.1.8. .7.....5.1....639.....72..1..1.9..65..2.3.1..96..5.2..3..82.....157....8.9.....2. .816.2....69.4......39..4....8....141..894..734....6....2..37......8.14....7.983. 1...6..858..2....73.5.8.9...8.7.9.3.....1.....2.3.6.7...8.9.7.62....3..965..7...3 2....358.....2...1...4.56.....9.4.68..5.1.9..61.8.2.....15.8...3...4.....263....4 3......89.1.6.......6..72..6..34..7.9.2.7.3.8.3..96..2..72..4.......9.2.12......3 4...3.1..5..6..7..23...9....7.4..3..19..5..67..4..7.9....9...74..5..2..6..1.4...3 4..2.7.8...3..85.6.786...4.2.....61.....2.....17.....4.5...346.6.15..2...3.1.2..8 48.6....2.6.85...4..74....8......82..2..9..5..15......1....52..9...82.4.2....6.17 6..8.23..84..5....25.7.....3....1.5.5..327..4.7.4....8.....4.86....1..72..25.8..3 64..9.5.8..748..1.5.81.......58...3...6...7...7...31.......84.9.9..513..7.3.4..61 7.......1.6...38.5.8..673.....7.1...3.1.5.7.4...6.9.....417..8.5.84...3.9.......7 8.6..43.9.7.8..5.4..........2..7..4.7.3.9.2.6.4..2..8..........4.8..2.9.2.95..8.7 9.74.....3...951.7.4...3.5.6....49.............31....8.8.7...3.7.153...4.....68.1 91...427.46...1..8...6...4....1...3.1.49.78.2.8...3....9...2...7..8...29.237...84

Code: Select all: # includes X-Wing(s) .......63..763.48...3..8..1.3...41.5.1..8..3.5.63...7.2..7..3...74.562..65....... ..3..2...7..93.1.5.1..4.2.3.2.5..9..4...1...2..7..4.5.9.4.2..6.3.1.59..7...4..5.. 5......4.24..1..75..8..7.....51.48..6...5...4..76.85.....7..4..83..2..67.5......3

by **wapati** » Fri Oct 06, 2006 9:00 am

daj95376 wrote:I doubt if RW is accepting Jellyfish for the EE thread, but here's some examples that I believe will qualify. They definitely qualify for the Superior Plus thread.

Code: Select all
8.6..43.9.7.8..5.4..........2..7..4.7.3.9.2.6.4..2..8..........4.8..2.9.2.95..8.7

This one is quite nice, it is easy except for the Jelly and the Jelly is hard to ignore. Good one!

by **Carcul** » Fri Oct 06, 2006 10:24 am

Here's the path I used for your first puzzle:

Code: Select all: *----------------------------------------------------* | 34 8 367 | 2 9 13 | 137 3467 5 | | 2 47 5 | 6 8 13 | 137 347 9 | | 9 1 36 | 7 5 4 | 2 368 368 | |-----------------+----------------+-----------------| | 5 9 4 | 3 2 78 | 6 78 1 | | 6 2 78 | 1 4 9 | 378 5 37 | | 78 3 1 | 5 6 78 | 4 9 2 | |-----------------+----------------+-----------------| | 34 47 9 | 8 1 2 | 5 367 367 | | 78 5 2 | 4 3 6 | 9 1 78 | | 1 6 38 | 9 7 5 | 38 2 4 | *----------------------------------------------------*

R5c7=7 or r7c9=7. But r5c7<>7 (due to the UR in cells r12c67). So r7c9=7 and the puzzle is solved.

Carcul

by **Carcul** » Fri Oct 06, 2006 10:49 am

For your second puzzle:

Code: Select all: *------------------------------------------------------------* | 5 278 9 | 478 6 78 | 1 247 3 | | 17 1678 2468 | 34578 45 35 | 79 4679 267 | | 3 67 46 | 9 1 2 | 57 4567 8 | |--------------------+-------------------+-------------------| | 8 4 3 | 56 7 9 | 2 1 56 | | 6 5 7 | 1 2 4 | 3 8 9 | | 2 9 1 | 356 8 356 | 4 67 567 | |--------------------+-------------------+-------------------| | 9 678 68 | 2 3 1 | 578 57 4 | | 17 1378 28 | 456 45 56 | 789 379 27 | | 4 23 5 | 78 9 78 | 6 23 1 | *------------------------------------------------------------*

Solution 1: Let's consider that r8c4 is not "4". Then we have r6c4=3 or r6c9=7, and r6c6=3 or r6c9=7: but this then means that r6c8 must be "6". Also, the UR in cells r19c46 tells us that in fact r8c4<>4. So, r6c8=6 and the puzzle is solved.

Solution 2:

[r7c7]=8|6=[r3c38]-6-[r3c2]-7-[r7c23]-8-[r8c3]-2-[r7c8|r8c9]-5,7-[r7c7],

and so r7c7=8 which solves the puzzle.

Carcul

by **daj95376** » Fri Oct 06, 2006 11:13 am

A similar approach for the first puzzle. Carcul's UR in [r12c67] forces [r5c7]<>7 and [r12c8]<>7. Coloring on <7> then forces [r7c9]=7.

I give full credit to Carcul for spotting the UR. My solver doesn't have UR Type 2 (yet) and had to fight its way through two XY-Wings and an XYZ-Wing to reach a solution.

by **Carcul** » Fri Oct 06, 2006 11:14 am

And for your third puzzle:

Wapati wrote:It is hard to avoid the Jelly, though forcing chains can avoid nearly any pattern, I guess?

It's quite simple to avoid that dangerous sea creature:

Code: Select all: *---------------------------------------------------------------------------* | 3578 358 35 | 56 9 1568 | 12 27 4 | | 2579 59 1 | 3 4 25 | 6 8 79 | | 289 4 6 | 7 128 128 | 3 5 19 | |----------------------+---------------------------+------------------------| | 358 1 35 | 2 7 4 | 58 9 6 | | 6 58 7 | 1 3 9 | 58 4 2 | | 4 2 9 | 8 56 56 | 7 1 3 | |----------------------+---------------------------+------------------------| | 1 6 2 | 4 58 578 | 9 3 578 | | 35 7 8 | 9 1256 12356 | 4 26 15 | | 359 359 4 | 56 12568 1235678 | 12 267 1578 | *---------------------------------------------------------------------------*

r3c1=2 or r4c1=3. But:

[r4c1]=3|2=[r3c1]-2-[r3c56]-1,8-[r1c46]-5-[r1c3]=5=[r4c3]=3=[r4c1]

and so r4c1=3 which solves the puzzle.

Carcul

by **Carcul** » Fri Oct 06, 2006 11:21 am

Daj95376 wrote:Carcul's UR in [r12c67] forces [r5c7]<>7 and [r12c8]<>7.

That UR also forces r1c7/r2c7<>3.

Carcul

by **daj95376** » Fri Oct 06, 2006 11:49 am

Carcul wrote:
Daj95376 wrote:Carcul's UR in [r12c67] forces [r5c7]<>7 and [r12c8]<>7.

That UR also forces r1c7/r2c7<>3.

Carcul

Does the UR force these eliminations in <3> ... or the resulting Naked Quad in [b3]?

by **daj95376** » Fri Oct 06, 2006 11:58 am

For your second puzzle.

Code: Select all: # SSTS, UR 1 in <78> => [r1c4]=4, Singles *-----------------------------------------------------------* | 5 278 9 | 4 6 78* | 1 27# 3 | | 17* 1678 2468 | 78* 5 3 | 79 4679 267- | | 3 67 46 | 9 1 2 | 57 4567 8 | |-------------------+-------------------+-------------------| | 8 4 3 | 56 7 9 | 2 1 56 | | 6 5 7 | 1 2 4 | 3 8 9 | | 2 9 1 | 3 8 56 | 4 67 567 | |-------------------+-------------------+-------------------| | 9 678 68 | 2 3 1 | 578 57 4 | | 17* 1378 28 | 56 4 56 | 789 379 27* | | 4 23 5 | 78 9 78 | 6 23- 1 | *-----------------------------------------------------------* XY-Chain 2-[r1c8]-7-[r1c6]-8-[r2c4]-7-[r2c1]-1-[r8c1]-7-[r8c9]-2 => [r2c9]<>2,[r9c8]<>2

and Naked Singles complete the solution.

by **Carcul** » Fri Oct 06, 2006 12:44 pm

Daj95376 wrote:Does the UR force these eliminations in <3> ... or the resulting Naked Quad in [b3]?

The UR (also) force those eliminations, but you are right, the emerging naked quad does the same thing.

Carcul

by **wapati** » Sat Oct 07, 2006 9:54 am

There are: x-wing, xy-wing, xyz-wing, finned-x and Urs of 3 types in here.
No one application, or even two solves it, you need lots!

The image is somewhat like a leaning scarecrow?

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

by **udosuk** » Sat Oct 07, 2006 11:41 am

wapati wrote:There are: x-wing, xy-wing, xyz-wing, finned-x and Urs of 3 types in here.
No one application, or even two solves it, you need lots!

According to Simple Sudoku, you only need 2 x-wings plus 3 finned-x/turbot-fish/simple-color moves to solve it...

The New Sudoku Players' Forum

Fun puzzle. So many methods to solve. No CHAINS required.

Fun puzzle. So many methods to solve. No CHAINS required.

3 types of UR

JellyFish

Another one that has lots of patterns

Re: Another one that has lots of patterns