# OLL skip method?



## Lt-UnReaL (Jul 20, 2007)

Someone that someone is making an OLL skip method? The last F2L pair orients all yellow edges and corners. Does anyone know anything about this?


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## Jason Baum (Jul 20, 2007)

I think you are talking about the MGLS method (Makisumi-Garron Last Slot). Macky came up with the idea for the method, but Lucas Garron came up with all the algs for it, and he can average sub 20 using it. Basically, you solve the F2L minus one pair. The last pair is broken up into two steps. First, you insert the edge of the final pair while orienting LL edges. Then, you insert the corner of the final pair while orienting LL corners. I want to say that there are 99 algs to this method, but I am not sure. It is a very interesting idea, and I'm sure it can be very fast.

You can read more about it as well as check out all the algs here:

http://cube.garron.us/MGLS/


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## Harris Chan (Jul 20, 2007)

Another way, which isn't as general, is to use the Winter Variation. On the last pair, when you pair the c/e and all the LL edges are orientated, you can use the Winter Variation algo to insert the last pair and orient the corners simultaneously. Of course if the LL edges aren't all oriented, then there's no use. 

Check out the WA algos at the "Files" section on Yahoo! Forum.

-Harris

P.S. Another korean person is also working on it, but very few algos, as to apply even when not all the LL edges are orientated. I need to dig out that page...I think you might have to be a member to view it.


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## Lt-UnReaL (Jul 20, 2007)

Jason Baum said:


> I think you are talking about the MGLS method (Makisumi-Garron Last Slot). Macky came up with the idea for the method, but Lucas Garron came up with all the algs for it, and he can average sub 20 using it. Basically, you solve the F2L minus one pair. The last pair is broken up into two steps. First, you insert the edge of the final pair while orienting LL edges. Then, you insert the corner of the final pair while orienting LL corners. I want to say that there are 99 algs to this method, but I am not sure. It is a very interesting idea, and I'm sure it can be very fast.
> 
> You can read more about it as well as check out all the algs here:
> 
> http://cube.garron.us/MGLS/



Interesting, but doing the edge+orientation step takes around 6.5 moves, whereas regular F2L would take about 7 moves. Then you place the corner in, and that takes about 9.5 moves, whereas OLL takes 9-10 moves. This method would be just as fast as F2L+OLL in my opinion, just 120 more algorithms to learn. It's an intriguing concept, though.



Harris Chan said:


> Another way, which isn't as general, is to use the Winter Variation. On the last pair, when you pair the c/e and all the LL edges are orientated, you can use the Winter Variation algo to insert the last pair and orient the corners simultaneously. Of course if the LL edges aren't all oriented, then there's no use.
> 
> Check out the WA algos at the "Files" section on Yahoo! Forum.
> 
> ...



I'm guessing you'll have one of these cases every 1/10 times, since there is connected and separated pairs, and 5 different ways the yellow edges can be oriented.
Is it possible to do this with separated pairs as well?
Also find that site, that would be cool.


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## joey (Jul 20, 2007)

Jason Baum said:


> I want to say that there are 99 algs to this method, but I am not sure.



I believe it is over a hundred. 125 I think. Although this is broken down into 13cases + mirrors and 56 cases+mirrors.

Harris: Are you talking about this: http://cubelife.oranc.co.kr/zb5/?sid=154
That gives a OLL skip after inserting the last pair. There's about 41 cases. Some of them are useful to recognize.


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## Lt-UnReaL (Jul 20, 2007)

This is a nice site.  These aren't all the cases, though. At the top it says there are around 200. These are probably the easy-recognition ones. I'll learn some of these and some winter variation.


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## Dennis (Jul 20, 2007)

Winter Variation: Maybe this perhaps http://4none.goodmeet.net/4none/WinterVariation.pdf


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## Lt-UnReaL (Jul 20, 2007)

Yeah, that's where Harris said to look.


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## gillesvdp (Jul 20, 2007)

I also made this method on my own.
I only know the basic cases.

http://www.gillesvdp.com/cube/docs/oll_skip/

Hope this helps.
Gilles


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## Lt-UnReaL (Jul 20, 2007)

I like how the Push Right alg page is simple and organized.  Any chance of you finishing the other 3(or 1 if you don't do mirrors)? This is like the Winter Variation + the separated pair algs. 

Another question...where and how does everyone create algorithms???


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## gillesvdp (Jul 20, 2007)

Thanks 
I will try and finish the other 3 during the summer.

However, only one will require me to work more than the others on it which is the "Pull-Right" (when the pair is split).

Did you get my number system that relates the number of the cases and the orientation of the corners ?


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## Lt-UnReaL (Jul 20, 2007)

Yeah, that's part of the reason why I think it is organized good.


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## watermelon (Jul 20, 2007)

Lt-UnReal: There are several cube solving programs that are used to find algs, the most popular of which are ACube and Cube Explorer. However, KSolve is another good option, since you can create your own "definition" files for any puzzle you like (thus it can solve any twisty puzzle).


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## Lt-UnReaL (Jul 21, 2007)

How do I get Cube Explorer to solve OLL states and F2L states? It always wants to solve the entire cube. :F


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## gillesvdp (Jul 21, 2007)

I have read that it would be possible starting with a new version (now already out) but it did not work.
Is there any option that has to be enabled or something ?

Anyway, I think ACube is very^100 powerful.


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## Johannes91 (Jul 21, 2007)

gillesvdp said:


> Anyway, I think ACube is very^100 powerful.


It's quite bad for solving many similar positions, because it doesn't save the pruning tables but generates them again every time. It took ACube 2 weeks to solve all 2x2x2 block positions, but with a better algorithm it can be done in a few minutes.


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## Lt-UnReaL (Jul 21, 2007)

ACube takes a lot of work. D: I got Cube Explorer to work. I gotta Ctrl/Shift + Left click the cubies.
Btw gillesvdp, I could help out with the algorithms for the OLL skip webpage.


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## gillesvdp (Jul 21, 2007)

I have to admit that writing all those generation codes to input in ACube is part of the reason I have not already finished this page. But if you have a better idea, feel free to do so. 

I am fully open to help for this page.


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## Johannes91 (Jul 21, 2007)

gillesvdp said:


> I have to admit that writing all those generation codes to input in ACube is part of the reason I have not already finished this page.


I always make a script to generate the input lines.

~U ? ? FR ? ! ! ! ! ? !! RFD ? ? ? @? !!
~U ? ? FR ? ! ! ! ! ? !! RFD +? ? ? @? !!
~U ? ? FR ? ! ! ! ! ? !! RFD ? +? ? @? !!
~U ? ? FR ? ! ! ! ! ? !! RFD ? ? +? @? !!
~U ? ? FR ? ! ! ! ! ? !! RFD +? +? ? @? !!
~U ? ? FR ? ! ! ! ! ? !! RFD ? +? +? @? !!
~U ? ? FR ? ! ! ! ! ? !! RFD +? ? +? @? !!
~U ? ? FR ? ! ! ! ! ? !! RFD +? +? +? @? !!
~U ? ? FR ? ! ! ! ! ? !! RFD -? ? ? @? !!
~U ? ? FR ? ! ! ! ! ? !! RFD ? -? ? @? !!
~U ? ? FR ? ! ! ! ! ? !! RFD ? ? -? @? !!
~U ? ? FR ? ! ! ! ! ? !! RFD -? -? ? @? !!
~U ? ? FR ? ! ! ! ! ? !! RFD ? -? -? @? !!
~U ? ? FR ? ! ! ! ! ? !! RFD -? ? -? @? !!
~U ? ? FR ? ! ! ! ! ? !! RFD -? -? -? @? !!
~U ? ? FR ? ! ! ! ! ? !! RFD +? -? ? @? !!
~U ? ? FR ? ! ! ! ! ? !! RFD ? +? -? @? !!
~U ? ? FR ? ! ! ! ! ? !! RFD -? ? +? @? !!
~U ? ? FR ? ! ! ! ! ? !! RFD -? +? ? @? !!
~U ? ? FR ? ! ! ! ! ? !! RFD ? -? +? @? !!
~U ? ? FR ? ! ! ! ! ? !! RFD +? ? -? @? !!
~U ? ? FR ? ! ! ! ! ? !! RFD +? +? -? @? !!
~U ? ? FR ? ! ! ! ! ? !! RFD -? +? +? @? !!
~U ? ? FR ? ! ! ! ! ? !! RFD +? -? +? @? !!
~U ? ? FR ? ! ! ! ! ? !! RFD -? -? +? @? !!
~U ? ? FR ? ! ! ! ! ? !! RFD +? -? -? @? !!
~U ? ? FR ? ! ! ! ! ? !! RFD -? +? -? @? !!


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## Lt-UnReaL (Jul 21, 2007)

Could you give an example of the script? :O


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## Johannes91 (Jul 21, 2007)

This is actually a really trivial case, because permutation doesn't change. Something like this would do (in Perl):

```
@foo = qw(? +? -?);
for $a (@foo) { for $b (@foo) { for $c (@foo) {
    print "~U ? ? FR ? ! ! ! ! ? !! RFD $a $b $c @? !!\n" } } }
```
Or functionally:

```
@foo = qw(? +? -?); sub _;
sub _ { if (@_ - 3) { _ @_, $_ for @foo }
        else { print "~U ? ? FR ? ! ! ! ! ? !! RFD @_ @? !!\n" } }
_ $_ for @foo
```
In general, just loop or use recursion to visit all positions. If you're not ignoring any pieces, then you have to deal with parities, but it's not a big deal.


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## gillesvdp (Jul 21, 2007)

Oh ok.
Could I do it using Python ?
That's the only language in which I have very little knowledge.


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## Lt-UnReaL (Jul 22, 2007)

I downloaded Perl 5.8.8. How do I install it now? xD


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## Johannes91 (Jul 22, 2007)

Python is a very nice language, surely you can use it for this. But you can also just email me when you need input lines for ACube and I'll generate them. I've done it so many times already that it's easy.



Lt-UnReaL said:


> I downloaded Perl 5.8.8. How do I install it now? xD


You're using Windows? I don't know, I only use Linux. It's sooo much better for hackers. But you'll probably find instructions if you google for it.


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## Karthik (Jul 22, 2007)

How do I make Cube Explorer generate the solutions to all the 1000+ LL cases??


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## ExoCorsair (Jul 22, 2007)

Lt-UnReaL said:


> I downloaded Perl 5.8.8. How do I install it now? xD



I run ActivePerl, from ActiveState (run a quick Google search, and run it with Komodo (also from ActiveState).


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## gillesvdp (Jul 27, 2007)

I just found my "Cube Book" in which I write various stuff about the cube, including algorithms I find (or have found by ACube) back.

And the "Pull-Right" algorithms are already in it so I will start making the webpage right now and finish it soon.

Here is the address: http://www.gillesvdp.com/cube/docs/oll_skip/


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## Lt-UnReaL (Jul 27, 2007)

I was thinking, how much time would this actually save? With a skip, you do the F2L case, and before you put in the pair, you gotta recognize and execute an alg to skip OLL. Without a skip, you do the F2L case, and then recognize and execute an alg to do OLL. They are both 2 looks, so does the skip method really only save 3 moves? (Actually maybe 5 moves since the algs are a bit shorter)


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