# parity fix?



## David Pritts (Apr 13, 2006)

Hey,

I am new to BLD solve, and have never even attempted one. However, every now and then I play aroudn with Stefan's method beacuse it seems very easy and I think BLDS is fascinating.

I have (at least a couiple times) followed the example solve walkthrough on Stefan's site, but I still have trouble udnerstanding how to use this method. THe problem is that I can usually not solve the last 2 edges, or last 2 corners, etc. 

Of course, I have never really sat down and tried for too long, but it just seems like I end up solving all of the pieces except for 2 and I don't know what to do to switch them, or how to avoid this.

Are there any resources on this, or does anybody have any tips?

Thanks!

David


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## Joël (Apr 13, 2006)

http://www.stefan-pochmann.de/spocc/blindsolving/3x3/

After the edge part, he explains how the 'parity problem' is handled.

Basically, the edges are solved, but the corners are not in the 'original', memorised positions (because URF and URB are swapped). In order to fix this, you basically swap URF and URB corners and UL and UB edges (I use an R permutation for this). Now, the edges are not totally correct, but the corners are in the memorised position again. Solving the corners will require to use the corner solving alg (R U' R' U' R U R' F') (R U R' U' R' F R) an odd number of times. This will also swap the UL and UB edge an odd number of times... So after doing the corners, the edges will automatically be solved as well...

To summarize:

1. Solve the edges (totally), using Pochmanns method.

2. In case of parity, do the correct R permutation, or if there is no parity, do nothing.

3. Start solving the corners.


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## David Pritts (Apr 14, 2006)

Joel, this was very helpful: thank you.

One of my goals for this spring break (all of next week off!) will be to successfully complete a BLDS.

Could anyone (who is willing to help me) post any AIM/Yahoo/MSN/whatever names they have so that I can get help quickly when I need it? Thanks (aim/y! preferable)

I am working on this right now.

David


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## bballkid2076 (Apr 17, 2006)

I am often confused on parity issues with pochmann method when there are pieces in the correct spot, but flipped. I am not sure how to count things like this. If anyone could explain this, it would be a great help. Thanks


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## pjgat09 (Apr 17, 2006)

These kind of cases are nothing to wprry about. Take the piece out in one way, then put it back in the other way. For example, say RY was flipped. You could take it out YR, then put it back in RY. There is also an alg to flip both the buffer and the other edge, but I don't use that. Maybe someone else can explain that.


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