# Parity is always r(a) perm?



## icetea666 (Sep 17, 2009)

So,if i don't apply R perm to fix parity on 3x3x3,after solving the edges,am i ALWAYS left with R(a) perm after i solved corners?


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## AvGalen (Sep 17, 2009)

Parity in this case means that you need to swap 2 corners and 2 edges. That can be done with both R-perms, J-perms or T-perm

If you don't tell which method you use we cannot help you


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## icetea666 (Sep 17, 2009)

AvGalen said:


> Parity in this case means that you need to swap 2 corners and 2 edges. That can be done with both R-perms, J-perms or T-perm
> 
> If you don't tell which method you use we cannot help you



Ah sorry.I use old pochmann.So any of these three can occur at the end?


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## Pr3miuM (Sep 17, 2009)

I also only know old pochmann. I start with the edges and when I have done an odd number of swaps that means I will have parity. I always make a Y' move and do the R-perm. Then Y again and continue with the corners.

I think it depends on what buffer pieces you use to get certain perms like the R J or T. But I haven't figured that out completely yet. But if you, just like me, use the "badmephisto" version of old pochmann then you will always end up with the same R-perm.


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## Sa967St (Sep 17, 2009)

I use the L perm for parity


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## StachuK1992 (Sep 17, 2009)

I use the Jperm, but I'm weird.


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## yoruichi (Sep 17, 2009)

if PLL cannot be set up < like 5 moves
then solving corners then edges or edges then corners is also a good way to fix parity


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## TMOY (Sep 18, 2009)

There aire also nice parity algs which are not PLLs.
For example: L' U L' Fw2 L U' L' Fw2 L2 U' (swaps UFL and UFR corners and UF and DF edges).


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## AvGalen (Sep 18, 2009)

yoruichi said:


> if PLL cannot be set up < like 5 moves
> then solving corners then edges or edges then corners is also a good way to fix parity


How would you solve "corners, then edges" or "edges then corners" when you have parity? The whole idea behind parity is that you cannot do that.

How would you solve a situation where ULF, ULB, DF and DB need to be swapped?


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## Stefan (Sep 18, 2009)

icetea666 said:


> am i ALWAYS left with R(a) perm after i solved corners?


No, you should do the R perm *before* solving corners. What it does is it exchanges the edge-solving-side-effect (URF<->UBR) for the corner-solving-side-effect (UL<->UB).


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## icetea666 (Sep 18, 2009)

Pr3miuM said:


> I also only know old pochmann. I start with the edges and when I have done an odd number of swaps that means I will have parity. I always make a Y' move and do the R-perm. Then Y again and continue with the corners.
> 
> I think it depends on what buffer pieces you use to get certain perms like the R J or T. But I haven't figured that out completely yet. *But if you, just like me, use the "badmephisto" version of old pochmann then you will always end up with the same R-perm*.



Can anyone confirm this?


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## Swordsman Kirby (Sep 18, 2009)

AvGalen said:


> yoruichi said:
> 
> 
> > if PLL cannot be set up < like 5 moves
> ...



I think he means something like F-perm + M2 U2 M2 U2 for that situation.


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## TMOY (Sep 18, 2009)

Why not simply F-perm with Rw2 as a setup ?


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## yoruichi (Sep 18, 2009)

k looks thats justa really nub case lets say u have UFR UBR and UL FR
id do T- perm F' MUM'U2MUM' F
many times its better to do something like that than akward 3 or 4 move setup
like y R' E R since theres no rotations


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## trying-to-speedcube... (Sep 19, 2009)

What about R U' R2 F-perm R2 U R' ?


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## yoruichi (Sep 19, 2009)

what are u switching?


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