## 6522Working on learning a 3-look LL

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• Sep 5, 2003
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What a very detailed reply Ryan!

Here's where I'm up to at the moment... I've learnt several LL edge
algs -- ones that mess with the corners (which doesn't matter if LL
edges are oriented first). I already knew several LL edge algs that
preserve the corners -- I guess these are useful if the corners are
already done when you get to the LL.

I already know the Sune and its mirror (can't imagine there'd be any
cuber who doesn't know this alg?!). I've learnt the algs for the
three LL corner orientation positions where 2 are corrent and 2
require twisting. Still need to learn the 2 algs for when all 4
require twisting.

I'm aiming to learn the 13 PLL if my enthusiasm lasts that long. In
case it doesn't, I planned the order that I would learn the algs.
First I revised the algs that just move the edges since. I knew U and
H, but for some reason was a bit iffy with Z. After that, I just
ranked them by 'probability of occurrence'. So, of the remaining 10,
I've memorised the algs with a frequency of 1/9 or greater (A, R, J,
G). So, 7 down, 6 more to go.

I think I need to take a break from new algs and spend some time
getting the newly memorised algs firmly planted in my head. I'm
finding that I can remember them without a problem, but I'm still
taking a bit of time recognising the patterns. I'm not concerned
though because I know that practise will fix this!

Jasmine.

--- In speedsolvingrubikscube@yahoogroups.com, Ryan Heise
<rheise@p...> wrote:
> On Mon, Sep 01, 2003 at 11:48:01AM -0000, jasmine_ellen wrote:
> > I remembered that DanK had something like this on his site about
a
> > beginner method, an intermediate method and an advanced method.
This
> > is actually what I was after. Who else has something like this on
> > their site?
>
> I'll describe the beginner and intermediate methods that I once
used.
> They are simplications of the Fridrich last layer system. You need
to
> first understand how that system works:
>
> http://www.ws.binghamton.edu/fridrich/system.html#last
>
> This general strategy, orienting first, then permuting, is good
because
> it is very easy to recognise the positions quickly. But instead of
> orienting all the pieces at once, you just orient the edges first,
and
> the corners second.
>
> BEGINNER METHOD
>
> First, orient the 4 edges (ie. make a cross). There are only 4
patterns,
> and one algorithm to solve them all! To view this, you need to use a
> fixed width font:
>
> --- --- -x- -x-
> -x- xxx xx- xxx
> --- --- --- -x-
>
> For each pattern, apply the algorithm "R'U'F'U F R" and it will
take you
> to the next pattern. Eventually you will end up with a cross.
>
> Improvement: notice that if you apply the algorithm when you already
> have the cross, you will end up with a line. That means that you can
> jump immediately from the 2nd pattern to the 4th pattern by
applying the
> algorithm backwards! So, this step should take an average of 6
moves.
>
> Next, orient the corners. There are only 6 patterns apart from
solved.
> Look through this complete list, and find all the patterns (and
> algorithms) that have a cross already formed:
>
> http://www.ws.binghamton.edu/fridrich/Mike/orient.html
>
> For the case when 3 corners need to be twisted, I recommend the
Sune TM
> algorithm from Petrus. See the applet at the top/right of his page:
>
> http://lar5.com/cube/fas6.html
>
> I think it's useful to learn to twist them forwards and backwards:
>
> - R U R'U R U2 R'
> - R'U'R U'R'U2 R
>
> To see that done fast, have a look at the quicktime movies at the
bottom
>
> http://lar5.com/cube/speed.html
>
> I recommend this algorithm because one of the other orientation
cases
> can be solved by just applying this algorithm twice. To know which
case
> I'm talking about, apply this to a solved cube: RU2R'U'RUR'U'RU'R'.
>
> Now, apply the sune (RUR'URU2R') twice:
>
> RUR'URU2R' + RUR'URU2R'
>
> Notice that the moves in the middle cancel out? So you can actually
do:
>
> RUR'URU'R'URU2R'
>
> which is an "optimal" solution.
>
> Next, permute the corners (yes, before the edges). Most of the time
> there will be a 3 cycle of corners. In this case, look at the 4
sides of
> the last layer. On one of the sides, the two last layer corners
will be
> matching in colour. Hold those two corners on the back side and do:
>
> R'FR' B2 RF'R' B2 R2
>
> Now the corners should be solved. If you don't find any two corners
that
> match, apply the above algorithm and that should result in a
position
> where two corners match. Don't worry, this case rarely happens. If
you
> want, you can learn a special algorithm for that case by picking the
> most attractive one from:
>
> http://www.ws.binghamton.edu/fridrich/Mike/permute.html
>
> The "Y" pattern on that page has the desired corner effect.
>
> Next, permute the edges. Again, most of the time, there will be a 3
> cycle of edges. You need to learn to cycle the edges forwards and
> backwards:
>
> - R2U FB'R2F'BU R2
> - R2U'FB'R2F'BU'R2
>
> Sometimes, all 4 edges need to be swapped in opposite pairs. That's
an
> easy case, so why not learn it:
>
> RLU2R'L' [U] R'L'U2RL
>
> The [U] means rotate the whole cube from the up side, 90 degrees.
>
> There's also a rare case where all 4 edges need to be swapped in
> adjacent pairs. The algorithm's difficult so it's not worth
learning.
>
> INTERMEDIATE METHOD
>
> First, orient everything like the beginner method. Then permute
> everything like the full blown Fridrich method.
>
> How can you learn all the permutations? See my previous email:
>
> c
>
> There, I list which algorithms to learn first, and which algorithms
to
> learn last.
>