Sadistic Sudoku Review


No, it isn’t a sadistic review. I’m reviewing Arnold Snyder’s Sadistic Sudoku collection of puzzles. Arnold’s solving advice, as presented in his “Sudoku Formula” books 2 and 3, will be analyzed in the following post. Two typical review puzzles are traced and illustrated.

Arnold and his publisher, Cardoza Publishing, describe his collection in Sadistic Sudoku, ©2012 as “200 extremely difficult, hair-tearing puzzles”. On the cover they are “brutally awesome . . . each one designed to sizzle your brain, frazzle your nerves”. Snyder also publishes three instructional books with puzzles, claiming to show ”never-before-published solutions … that unlock the most difficult expert-level puzzles quickly and easily”.

Naturally, such claims demand sysudokie attention. Snyder’s Sudoku Formula 3 came out in 2010, and Sadistic Sudoku, his capstone collection, in 2012. Where has it been?

Well, let’s find out what I’ve been missing. First of all, how does the Sysudokie Order of Battle protect your composure and your hair as you embark on Sadistic Sudoku? This will tell us if any of the never-before-published methods of Arnold’s are actually required. I started with number 5 and took every 20 to 185, for the following review table.

sadistic review tableNo threat to your composure or hair, but rough on Arnold’s pants, which are ablaze. One Sadistic is a victim of box marking, five more don’t get past basic. Survivors carry generous fields of bv, and are easily cut down by XY-chain almost nice loops and color wraps. Four x-wings, two unique rectangles, three naked triples, two hidden singles, and a naked single show up in line marking. The bypass stingy puzzles starting with six free cells per line may threaten a few follicles, but melt into naked triples before any hair comes out.

For illustration, let’s go through two, your homework puzzle 25, and the stingy 185.

Sad 25 basic trIn 25, the bypass closes 17 cells by clues or naked pairs, and the 9 pattern. Box marking and line marking are not difficult.

Sad 25 LM gridThe line marked grid shows the 1-wing and a typically generous bv field. As a matter of form I scanned for Sue de Coq and XYZ-wings, but was really pushing to draw the XY railroad and start coloring.

 

 

Sad 25 railroadHere’s my railroad. It easily produces some prodigious XY-chains and toxic pairs.

 

Below, I found the long black ANL looking for results on an even longer nice loop. The eliminations seemed indecisive, so I continued looking along the tracks.

Sad 25 two ANL

 

The red chain elimination leaves a clue and a boxline.

Updating the grid, I get SWnp15 and another ANL shown below. That’s two more bv.

In Sudoku Formula 3, Arnold recognizes the XY nice loop, calling it a cycle. I found no cycles on the railroad.

But apparently, Arnold missed the much more frequently occurring Almost Nice Loop, in XY-chain or other AIC form.

Or maybe he’s saving all that for the Arnold Snyder Sudoku Formula 4.

Sad 25 third ANLIn any case, why bother updating the railroad. With such a bv field, the crayons leap out of the box themselves.

Bad news. Arnold doesn’t do Medusa coloring either.

Sad 25 coloring

In our blue/green cluster, there is a double trap in the South Box, but it’s a game over home run when two greens compute into the same cell in the North box. The blue army of new clues is overwhelming.

I’ll report on how close Arnold comes to coloring, and where he goes instead, in the next post.

 

 

For now, we’ll see what happens to stingy Sadistic 185.

Sad 185 tr to nt 1After two cells are closed in the bypass, and no clues arrive in box marking, a hair tearing line marking is taking shape.

Sad 185 nt 1 grid

A naked triple jumps out, and it seems a little less grim. But now we have to deal with seven free cells per line. Ugly.

There are five five unmarked rows and five unmarked columns, all 7f.

 

 

But if you think this is bad, try it without line marking.

I go with rows, for no good reason.  I should have seen it when 2r7c9 was removed, but 2r7c2 is now a naked single.

Sad 185 SWns2

 

However, not much time is lost when it turns up in the marking of row 7.

Look at those fill strings. Its sadistic. Like a monster.

 

 

Sad 185 two nt bxl

 

Incredibly, the marking grinds to a halt after naked triples in W and r4, and a decisive boxline Cr5.

 

 

 

 

Sad 185 LMm1

 

 

During this marking, the unmarked row 9 let 185 off the hook again and again, leaving this line alone to finish.

But just as I formed the fill string, I noticed that S1 had confined S3 to r9c6.

 

 

This was enough to make Sadistic 185 give up.The trace to garbage time follows,

Sad 185 final tr

Sorry for the overly long post. Next, in more reasonable doses, is a review of Arnold Snyder’s instruction books, the Formula series. First I consider his basic solving method, as described and illustrated in Sudoku Formula 2. If you have that book, I’ll be working through puzzles 5 and 6, for comparison.

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About Sudent

My real name is John Welch. I'm a happily married, retired professor (computer engineering), timeshare traveling, marathon running father of 3 wonderful daughters and granddad to 7 fabulous grandchildren. The blog is about Sudoku solving. It covers how to start, basic solving to find candidates efficiently, and advanced solving methods in an efficient order of battle. It is about human solving methods, not computer solving.
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