SudokuSolver Forum

There are three difficulties to choose from.
All three puzzles have the same solution.

A) Novice.
B) Apprentice (mainstream edition).
C) Master (65 Intersections, 7 Naked Pairs, 2 Naked Triplets, 4 Naked Quads, 1 Hidden Pair, 1 Y-Wing in g10). Select to view GRID numbers.



Regular Clueless Explosion #31A (Novice)

Rating based on required solving techniques:  Moderate

000700000000000004306050000018002000000000103070500200000000000009000001560074308
000700000000003000100020400080000050000005900010300008007801004000000007300070500
040009002107000004005000000906800000000000001000090030000000020800007000004005100
000000005005700000200600004050000000700000403002406800000000000000000000040083001
800003070400000000000400021000006000000000300910050008090000400002009000003001005
000000409000200000070058001500001040900005000300000800003000006000600900001007000
300002000000000000050019020000000090208000300000000600000000060500008000096450000
005010090000007400900000000000003002001000300009200014100000008002700000004005063
004006000500000100700200800000030070600700900010000000000004059006000000008060201



Regular Clueless Explosion #31B (Apprentice)

Rating based on required solving techniques:  Hard

000700000000000004306050000018002000000000103070500200000000000009000001560074308
000700000000003000100020400080000050000005900010300008007801004000000007300070500
040000002107000004005000000906800000000000001000090030000000020800007000004005100
000000005005700000200600004050000000700000403002406800000000000000000000040083001
800003070400000000000400021000006000000000300910050008090000400002009000003001005
000000400000200000070058001500001040900005000300000800000000006000600900001007000
300002000000000000050019020000000090208000300000000600000000060500008000096450000
005010090000007000900000000000003002001000300009200014100000008002700000004005063
004006000500000100700200800000030070600700900010000000000004009000000000008000201



Regular Clueless Explosion #31C (Master)

Rating based on required solving techniques:  Absolutely Super Hard

000700000000000004306050000018002000000000103070500200000000000009000001560074308
000700000000003000100020400080000050000005900010300008007801004000000007300070500
040000002107000004005000000906800000000000001000090030000000020800007000004005100
000000005005700000200600004050000000700000403002406800000000000000000000040083001
800003070400000000000400021000006000000000300910050008090000000002009000003001005
000000400000200000070058001500001040900005000300000800003000006000600900001007000
300002000000000000050019020000000090208000300000000600000000060500008000096450000
005010090000007000900000000000003002001000300009200014100000008002700000004005063
004006000500000100700200800000030070600700900010000000000004009000000000008000201

_________________
Quis custodiet ipsos custodes?

Normal: [D  Y-m-d,  G:i]     PM->email: [D, d M Y H:i:s]

I was wondering why one mere y-wing would merit a rating of "absolutely super hard"....but jsudoku indicates there's a number of other required advanced techniques....I think I'll settle for the mainstream version on this one

The Y-Wing is needed pretty early on and is hence very difficult to spot.
Except the Y-Wing, all the other advanced techniques listed by JSudoku are red herrings and factors into the difficulty rating.

Using my solvers' sequence, JSudoku produces the following list of techniques used:

436 Naked Singles
121 Hidden Singles
 70 Intersections
  8 Naked Pairs
  2 Naked Triplets
  4 Naked Quads
  1 Hidden Pair
  1 Swordfish
  1 Skyscraper
  3 Two String Kites
  5 Empty Rectangles
  1 Turbot Fish
  1 Finned Swordfish
  2 Grouped X-Wing
  5 Grouped Turbot Fishes
  1 Y-Wing

If you find the Y-Wing first, none of the other advanced techniques are needed, and the list of required techniques reduces to:

409 Naked Singles
148 Hidden Singles
 62 Intersections
  5 Naked Pairs
  1 Naked Triplet
  2 Naked Quads
  1 Y-Wing

_________________
Quis custodiet ipsos custodes?

Normal: [D  Y-m-d,  G:i]     PM->email: [D, d M Y H:i:s]

jsmif,

if you have the time, please do the following and then give some feedback about my rating:

1. Solve RCE #31C with JSudoku, Ctrl+Shift+D
2. In the log locate the Y-Wing solving description and copy it to for instance a TextPad window.
3. Repaste RCE #31C into JSudoku and do single step solving (Ctrl+D) until the first advanced move
   (Skyscraper in Clueless:C29: (2): RTC5=RHC5-RHCT=RMCT -> RMC2, RTCMQ <> 2)
   is done and then undo it with Ctrl+Z
4. Using the information from step 2 locate the Y-Wing.
5. Picture yourself finding this Y-Wing unguided, and try stipulating how hard that would be.

Some information:
The rating philosophy behind RCE #32C/D and RCE #33C are similar to RCE #31C.
If you have problems spotting the single advanced technique required, please peep at the cloaked grid number.
That's why I bother providing it.

RCE #33C is a real bastard.
Therefore do I not only provide the grid number cloaked, but also the digit, and a hidden image of the single required advanced technique .... an Intergrid Finned X-Wing, that looks nothing like its name.

_________________
Quis custodiet ipsos custodes?

Normal: [D  Y-m-d,  G:i]     PM->email: [D, d M Y H:i:s]

Hmmm....that would be fairly findable much later in the solving process, if the intergrid puzzle were already solved and the y-wing was in an individual puzzle....but with so much of the puzzle still unsolved, this would be really tough for me to find.

I'm still at the "apprentice" level of training myself to find xy-wings and y-wings (when I tried samurai #31c over the weekend I spotted -- darn it -- only two of the four xy-wings, and couldn't find the y-wing, without assistance), so I'm sure this would not be too tough for the real experts out there....but yeah, I definitely agree with the rating, and could see myself wasting quite a lot of time on the herrings first