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tlanglet · Posted: Mon Sep 22, 2008 3:38 pm Post subject: Vanhegan Fiendish 9/21

Another Vanhegan Fiendish from September 21 to enjoy.

I used several steps to solve it but suspect that many different solutions are possible.

nataraj · Posted: Mon Sep 22, 2008 4:52 pm Post subject:

After basics,

daj95376 · Joined: 23 Aug 2008 Posts: 3854

tlanglet · Posted: Mon Sep 22, 2008 5:23 pm Post subject:

My routine sequence started with
the UR<68>,
two w-wings (on <69> and then <56> with a transport) and finally,
a skyscraper on <6>.

I thought the puzzle was a VH level, but was not an obvious one-stepper.

Ted Smile

daj95376 · Joined: 23 Aug 2008 Posts: 3854

tlanglet · Posted: Mon Sep 22, 2008 5:43 pm Post subject:

Very nice solution Nataraj Exclamation

I also have been doing more transporting of pincers, even when they directly provide eliminations. In this puzzle I transported the pincer at r6c4 of the useless w-wing <56> to r4c3 using the strong link in box4 thereby getting the identical eliminations you achieved in your second set of eliminations.

Ted

arkietech · Posted: Mon Sep 22, 2008 5:43 pm Post subject:

I used an x-wing, skyscraper, er and Sue DeCog to bust it without chains.

nataraj · Posted: Tue Sep 23, 2008 6:02 pm Post subject:

Thanks, Ted ! Very Happy

Of course, what I found is just a w-wing with transport. And writing it down as such (or just give the AIC) would have sufficed to describe the solution. As daj95376 pointed out, not all of the eliminations are needed, but then, I found them easily in one step and just used them simultaneously Smile

Even more than in the solution itself I am interested in the various (and sometimes quite ingenious) ways people tackle difficult sudokus. And if a process (or a certain technique) offers effectiveness AND efficiency, this is something I like - as long as it does not become just dull routine. Drawing the little diagrams and looking at them is much easier on my eyes and brain than looking at the full grid - while still providing sufficient challenge.

If only I could find a way to combine both the diagrams (which provide support for coloring, multi-coloring, ER, w-wing, m-wing and combinations thereof) with keith's only partially filled grids (solo and bi-values), which make it very easy to spot xy-wings ...

Problem is, the diagrams visualize mostly strong links, wheras xy- and xyz-wings work with weak links, too. Well, we must leave some challenges for future generations, lol.