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Earl · Joined: 30 May 2007 Posts: 677 Location: Victoria, KS

No firecracker for the Fourth. Same old, same old.

Solution: 235 xy-wing does it

Early Earl

tlanglet · Posted: Sat Jul 04, 2009 3:40 am Post subject:

Yes, it took a few minutes to complete basics and only a few seconds to finish the puzzle. However a second view provided me a more interesting one step solution:

crunched · Joined: 05 Feb 2008 Posts: 168

I am pretty sure the below grid has all the basic digits squeezed from it. It took me quite awhile (for some silly wrong-headed reason) to find the magical wings: 23-25-35, or 23-35-25. The middle numbers above = pivot. I bet you virtuosos finished the puzzle in a matter of a few minutes, with taking a bathroom break & getting up and getting a cup included in the total time.

David · Joined: 02 Jun 2006 Posts: 58 Location: Bedford, UK

There seems to be a very large number of solutions to these puzzles using xy or xyz wings . Presumably due to the way in which they are constructed ?

Captain Pete · Joined: 09 Jun 2007 Posts: 55 Location: Oley, PA

Using Crunched's grid above, in blocks 7,8, and 9 there is a pattern of six 259s with one including a 3. Can we assume that similar to a rectangle, the one including the 3 must always be a 3?

wapati · Posted: Sat Jul 04, 2009 1:49 pm Post subject:

That is a valid deduction. Good spotting.

cgordon · Joined: 04 May 2007 Posts: 769 Location: ontario, canada

Singles followed by a one-step solution - in my case an ER on <2>.
They don't get no easier!

PS. I didn't follow Captain Pete's 259 logic.

crunched · Joined: 05 Feb 2008 Posts: 168

Did you see an xy or xyz wing, apart from the two xy wings that I point out above? I did not see anything else, and as I mentioned it took me quite awhile before I came up with what I did---which means that I felt as though I inspected everything before I finally found the solution. It was seemingly an especially long time because, after removing all of the basics, much of the puzzle seemed to be complete.

I don't know how these puzzles are constructed. A curious thing to me is that I never seem to be able to solve a "hard" (as opposed to "very hard") puzzle using wings. Of course wings (considered an advanced technique) are not supposed to be necessary in hard puzzles. Yet, one would expect to be able to find and use them where helpful. But I repeat: I never, never find wings in a hard puzzle.

tlanglet · Posted: Sat Jul 04, 2009 5:06 pm Post subject:

My earlier post identified the possible DP involving the three digits 2, 5 & 9 plus a single cell, r7c9, that has the extra digit 3. This condition is similar to the Type 1 UR situation thus, as I previously noted, r7c9 must be a 3 or the puzzle would not have a single solution.

Ted

storm_norm · Joined: 18 Oct 2007 Posts: 1741