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

I needed a one-two punch. Norm, please find a single blow.

A Solution: x-wing (5), then xy-wing (168)

Early Earl

Marty R. · Posted: Sat Jan 30, 2010 4:50 am Post subject:

Could I have screwed up twice? (Of course). I finished it with basics only both times.

storm_norm · Joined: 18 Oct 2007 Posts: 1741

overkill

(6=5)r3c5 - (5)r13c4 - (5)r8c4 - UR46[(5)r8c6 = (7)r7c3] - (7=6)r7c3 - (6)r5c3 = (6)r5c56;
r6c5 <> 6

Clement · Posted: Sat Jan 30, 2010 7:09 am Post subject:

The XYZ-Wing <16>-<156>-<56> which eliminates 6 in r5c6 followed by the
x-wing 5 also soves it.

Clement · Posted: Sat Jan 30, 2010 7:11 am Post subject:

The XYZ-Wing <16>-<156>-<56> which eliminates 6 in r5c6 followed by the
x-wing 5 also solves it.

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

I used the XYZ-Wing <156> followed by colouring on <6>. There's a Type 6 UR on <46> but I don't think it is useful.

George Woods · Joined: 28 Mar 2006 Posts: 304 Location: Dorset UK

The much despised DR gives a one stepper. if R2c8 is 9, r1c2 is 5 & a 16 DR is revealed so r2c2 is 9 ..... Interestingly kowing that r2c8 is not 9 - setting it to 9 fairly quicky gives not only the DR but a more direct failure! i.e maybe one doesn't have to rely on the DR!

arkietech · Posted: Sat Jan 30, 2010 5:10 pm Post subject:

Another one stepper:

Wendy W · Joined: 04 Feb 2008 Posts: 144

Marty, I did it twice with basics only, too. I thought I just got lucky the first time so I tried again. Same thing.

Marty R. · Posted: Sun Jan 31, 2010 1:36 am Post subject:

storm_norm · Joined: 18 Oct 2007 Posts: 1741

alright you two who solved it with just basics.
maybe you can write up a play by play??

something like.
r2c3 is 6
r1c9 is 7

naked pair here,

naked pair there,

etc... etc.... etc....

or at least post the grid where the puzzle falls to only singles.

Marty R. · Posted: Sun Jan 31, 2010 5:11 pm Post subject:

George Woods · Joined: 28 Mar 2006 Posts: 304 Location: Dorset UK

arkietech gives reasoning:_

(2)r1c7 = (2-8)r4c7 = (8-5)r4c6 = (5)r4c2 - (5)r1c2 = (5-2)r1c4 = (2)r3c4 => r1c4<>2

I have tried to a) understand this and b) Since I didn't understan it to find a primer for the language.

Th Logic might be the equivalent of:- putting a 1 at r1c7, gives r5c7 as 8, r4c6as 8 r4c2 as 5 and r1c2 is 1 - diaster two 1s in row 1 so initial postulate is false so r1c7 is 2

I don't quite see the equivalence of this to the quoted text

Can anyone direct me to a page that defines this nomenclature!

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

Personally - that nomenclature is not my cup of tea anyway. Looks more like computer proramming. Takes things from the level of fun to pain.
But I guess - one man's meat.....etc

arkietech · Posted: Sun Jan 31, 2010 6:35 pm Post subject:

Wendy W · Joined: 04 Feb 2008 Posts: 144

I join Marty in that stipulation! Whether we both made a lucky "erasure" or what, I don't know, but I just tried to write it out step by step (what else is there to do, no football on this afternoon) and in fact couldn't do it this time with basics alone. Darn it!

sudocraz · Joined: 28 Apr 2008 Posts: 53

I got this with basics too, but my husband didn't. I must have made a lucky error somewhere because when I did it over I needed an x-wing and an xy wing to get it. Embarassed

Stanley P · Joined: 27 Feb 2008 Posts: 20 Location: Tennessee, USA

Interesting comments here so I thought I would add mine. I don't understand the nomenclature (yet) so went at it this way:

I got to Norm's post pretty quickly. Looking at r3c8, making it 2 gives a 6 in r4c8 and making it a 9 gives a 6 in r2c1. So, r4c1 is 1.

Then, using r4c2, making it a 6 puts a 2 in r4c8 and making it a 5 puts a 2 in r1c7. Therefore, r3c8 must be a 9, and that solved it for me.

These moves might be "basics" but they do have the flavor of wings of some sort. Of course, George's DR or his use of r2c8 are another way to get to the solution using what are pretty much basics.

This one was a little different for a VH.

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

Stan: That looks like guessing - or trial and error - which is a NoNo for VH puzzles. You should learn some of the VH techniques - wings and things. I used this: http://www.sudocue.net/guide.php but there may be others.

Cheers, Craig

Stanley P · Joined: 27 Feb 2008 Posts: 20 Location: Tennessee, USA

Hey Craig,
I'm feeling a little defensive in that I used the 156 XYZ wing to get to Norm's post, and I feel pretty good about XYs and X wings. I guess I just couldn't see the X wing others mention as the solution. I still don't see how so many got there with just "basics."