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Parity or Not? Other 3x3 BLD thoughts

jdh3000

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Apr 4, 2017
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Is anyone bypassing parity in bld?
I just refreshed my memory of the old pochmann method to start blindfold solving again. I always found parity a nuisance because it didn't seem to come up that often, and when it did I'd have to refresh my memory of the alg.

I watched a jperm video statimg one could skip parity by swaping two pieces. It's longer but I wouldn't have to keep up the parity alg.

Also one thing that was a problem was making sure I had all of my pieces memorized. If there's any good way to keep track of pieces I'd live to know it. Many times I'd do what I thought was a perfect solve only to open my eyes to see a mess.
 

GenTheThief

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(I am not a world class BLD solver but I know enough to be somewhat competent)

Using a memory palace/journey/roman rooms/loci whatever the hell you want to call it is a really useful tool for storing your memo. It's more a technique used for MBLD, but if you're having trouble with 3BLD memo, it can help with consistency.

Regarding parity, it happens to be a fair bit, so I've never really needed to refresh my memory on the alg. I don't know the exact stats (I don't think it's just 1/2), but if you're doing any sort of sessioning, you'll run into it a lot. Swapping pieces is also something that I've done, but I think it's a bit more for MBLD since it requires you to alter your tracing a little bit for only a marginal simplification of memo, which isn't really something that is going to help in a world class BLD solve. In MBLD, where memo is a huge part, it can definitely help out.
 

jdh3000

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Ok I just realized parity is just an R perm(don't know why I didn't see that before), just the one I used to use for parity wasn't the R perm I normally use for PLL, it was a little longer with some D moves and seemed awkward to remember.
I'll just use the one I'm used to and that'll solve that.
 

xyzzy

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I watched a jperm video statimg one could skip parity by swaping two pieces. It's longer but I wouldn't have to keep up the parity alg.
(Assuming you're using white-top green-front orientation, OP with ULB buffer for corners, and c/e memo order, e/c exec order.) After memoing the corners as usual, if you have an odd number of targets, memo the edges but treat white-orange as white-blue and vice versa. If you do that, then you'll have an even number of edge targets.

After solving the edge targets with this modified memo (with M2 or 3-style or whatever), you'll be left with UB-UL swap, and after doing an odd number of OP corner algs, those two edges will be swapped into the correct location, leaving the cube fully solved.

This isn't longer. It's strictly better than going out of your way to do an R perm or some weird rMUD alg. The only downsides are that it locks you into ceec order, and that it's a bit weird to have to pretend orange is actually blue and vice versa when you first use this method.
 

jdh3000

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Does memorizing get easier? I've always had to write down letter pairs, then make up the mnemonic device.

I'd like ti get to where I can do it without writing it down first.
 
Last edited:

jronge94

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Does memorizing get easier? I've always had to write down letter pairs, then make up the mnemonic device.

I'd like ti get to where I can do it without writing it down first.

Memo just boils down to practice. You'll get better at it. Also a cube is only about 10 letter pairs (20 letters) on average so you'll be able in no time to memo it.

One last thing, even though I love Jperm and his videos, I personally think his bld tutorial i quite bad, or at least lacking in information.
Do with this info what you will, but I'd at least recommend to understand bld better to at least take a look at Noah Arthur's tutorial (which imho is the best bld tutorial on YT)


I did watch the entire series 2 or 3 times, butit really made me really understand what I was doing, which made bld more run for me.
 

abunickabhi

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Jperm tutorial is not focussed enough, Noah's tutorial is old and kind of outdated, Jack Cai's tutorial is really good but does not go in detail and in depth with the nuances, same case with my tutorial (not deep and specific enough), Josh Weimer's tutorial is outdated too, Timothy Goh's tutorial is good explanation but old and outdated algs used, Graham is current making a tutorial on 3-style and it will be best as he is best most helpful blinder out there.
 

Kit Clement

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Regarding parity, it happens to be a fair bit, so I've never really needed to refresh my memory on the alg. I don't know the exact stats (I don't think it's just 1/2), but if you're doing any sort of sessioning, you'll run into it a lot.

If any 3x3x3 state were a possible scramble, parity would be exactly 1/2. However, a WCA scrambler technically excludes the solved state, 1 move scrambles, and 2 move scrambles. There are 6 possible 1 move scrambles, which have parity, and there are 25 possible 0 or 2 move scrambles, which don't have parity. Thus, it's technically slightly above 50% chance of getting parity, but there's really no practical difference from 50%.
 

jdh3000

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Apr 4, 2017
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I just did my first successful BLD solve since I started back. My first full attemtp right before left a 3 pieces unsolved. Not to make excuses but there was an interruption, may or may not have turnes out that way.

It didn't seem as difficult as before, but my goal is to solve without writing anything down. I'm going to watch the video/tutorials y'all suggested to see if I can get a better memory system going.

I'm toying with a new idea(probably not new, just something I thought of), and if it works I'll share it. It probably won't be much help to anyone except a beginning BLD solver, but I want to get to be like those of you who don't have to write it down.

Still in all, opening one's eyes to see a solved cube feels pretty good, even if it took a while to set up.

I appreciate all of the advice! Hopefully I'll stick with it tgia time...
 

jdh3000

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Apr 4, 2017
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This may sound ignorant, but the alternative to doing parity using old pochmann is edge swapping.

My question is if I'm going to edge swap to avoid doing the parity alg, do I need to edge swap in the middle, between edge and corners, or can it be done on the end.

The jperm video I first learned bld from said if you didn't want to do the parity alg, just remember to do the edge swap.

My thoughts are that if corners are done first, then the edge swap could be done on the end, but if corners are done last, the edge swap would be in the middle because it's also flipping corners. Am I correct in this?

I went through a few sighted solves and couldn't work it out.

I know this probably should be obvious but not for me... thanks!
 

jdh3000

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Apr 4, 2017
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Can you change to thread topic from 'Party Alternative Question' to 'alternative question about parity'?

Also merge this thread with the thread xyzzy mentions.

Well it actually wasn't an "alternative question", but was a question regarding an alternative to doing a parity algorithm, that's why I phrased it like that.

I'm sorry but I don't know how to merge a thread...how do you do it?

I apologize for not remembering a similar thread I had posted before.
 
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jdh3000

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Apr 4, 2017
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I think my post in your earlier thread covers the important points already? If there's something there that needs clarification, feel free to ask.


Ok I think I have it... I muddled through a sighted solve just to be sure of what was happening.

I have the U layer is lettered A, B, C, and D for the edges. I just have to memo the corners first, if they are odd, I know there is parity. Then I memo edges, but when I have an edge going to A, I send it to D instead, or vice versa if D comes up.

Memorizing this way leaves an even number for the edges. Then when I solve the corners it will fix solve the whole cube.

It worked out in practice, so tomorrow I'm goint to attempt a BLD using this.
If I don't end up with parity on the first scramble I figured out I can force it with an edge swap.

Thanks for tge advice, it just took a bit to sink in.
 

jdh3000

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Joined
Apr 4, 2017
Messages
138
I think my post in your earlier thread covers the important points already? If there's something there that needs clarification, feel free to ask.
(Assuming you're using white-top green-front orientation, OP with ULB buffer for corners, and c/e memo order, e/c exec order.) After memoing the corners as usual, if you have an odd number of targets, memo the edges but treat white-orange as white-blue and vice versa. If you do that, then you'll have an even number of edge targets.

After solving the edge targets with this modified memo (with M2 or 3-style or whatever), you'll be left with UB-UL swap, and after doing an odd number of OP corner algs, those two edges will be swapped into the correct location, leaving the cube fully solved.

This isn't longer. It's strictly better than going out of your way to do an R perm or some weird rMUD alg. The only downsides are that it locks you into ceec order, and that it's a bit weird to have to pretend orange is actually blue and vice versa when you first use this method.

I did this just now and it worked great!!!
It's going to take some getting used to but this is going to be better that a parity alg or swapping edges.

Thank you so much for telling me about it again. I admit I didn't get what you were saying the first time but it's clear now, and makes perfect sense!
 
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