Stuck near end

List of contributions in 'Help with this one please'

Help with this one please contributed by Luke

Anybody help please. What strategy might take this further? thanx.

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Look at the 8s (re: Help with this one please) contributed by Huw

I think your best bet is to look at the 8s for this puzzle.

When I get stuck near the end of a puzzle I scout through all the numbers with a few squares left (not too many like 3 or too few like 2 in this case).

Only the 8s look promising and the way I work it is to mentally work through an either or case. Look at center region with only De or Ee as possibilities. If an 8 went in De then this means an 8 must go in Eb this is because Fc could not be an 8 as Fh is the only square in Dg that can now take an 8. That then forces an 8 in Gc. But that's impossible because theree is now no square in region Gg that can take an 8 any more. Ih can't because of the 8 in Fh and can't in Gi either. So the initial test for De as 8 was wrong.

Therefore it must be allocated in Ee not De...

Some clever person will no doubt spot this as a Swordfish scenario which precludes De but I'm no expert just a plodder... There are certainly four rows with only 2 8s in them and I think that discounts De and Dh.

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Good Thinking (940) (re: Look at the 8s) contributed by Luke

Very good, I was able to solve it now.

I wonder if this was really a swordfish or if there was logic ways of solving beyond 'established' rules.

Thanks again.

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Swordfish confirmed (re: Good Thinking (940)) contributed by Alexander

It certainly looks like a swordfish to me.

As long as you have a set of rows with only TWO squares that a possibility can go in and these rows interconnect either as a box (X-Wing) the same rule applies - you can knock out the intermediate ones in De and Dh.

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