Insertions

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Insertions

Would anyone give me a brief introduction to insertions?

A tutorial would be nice...
arenol

Posts: 9
Joined: Sun Jul 10, 2011 9:47 pm

Re: Insertions

Do you mean intuitive f2l?
Or Multislotting?

An insertion is when you put a piece into an empty spot, so it's too vague to understand what you really want for a tutorial.
lol, here to help ^_~
Sharkretriver

Posts: 367
Joined: Thu Jul 14, 2011 10:11 pm

Re: Insertions

I'm referring to the FMC technique where an algorithm is inserted somewhere in the general progress. It appears to me that it is an important ingredient in shortening solutions to less than 30 moves. But I don't quite understand the basic idea and how they figure out what to insert when.
arenol

Posts: 9
Joined: Sun Jul 10, 2011 9:47 pm

Re: Insertions

http://www.dtwoner.110mb.com/index.php?p=1_4_FMC
lol, here to help ^_~
Sharkretriver

Posts: 367
Joined: Thu Jul 14, 2011 10:11 pm

Re: Insertions

I think I'm getting the idea.

The other day I solved the entire cube except three corners in 25 moves. Unfortunately, solving the remaining corners would take another 10 moves (need a conjugate and commutator to solve it). That makes it a 35 turn solution.
However, If I track the three corners throughout the solve, I might come across a situation where I can cycle them in 8 moves (without conjugation). Such an insertion alone is two turns saved (but I didn't find any in this case).
Furthermore, I might even find a place where I can cycle them in a way that the first moves of the insertion is the reverse of the last few moves up to that point, or the last moves is the reverse of the subsequent moves after the insertion. That can also save a number of turns, I guess. (I'll look into that case now...)

Or am I on the wrong track here?
arenol

Posts: 9
Joined: Sun Jul 10, 2011 9:47 pm

Re: Insertions

arenol wrote:I think I'm getting the idea.

The other day I solved the entire cube except three corners in 25 moves. Unfortunately, solving the remaining corners would take another 10 moves (need a conjugate and commutator to solve it). That makes it a 35 turn solution.
However, If I track the three corners throughout the solve, I might come across a situation where I can cycle them in 8 moves (without conjugation). Such an insertion alone is two turns saved (but I didn't find any in this case).
Furthermore, I might even find a place where I can cycle them in a way that the first moves of the insertion is the reverse of the last few moves up to that point, or the last moves is the reverse of the subsequent moves after the insertion. That can also save a number of turns, I guess. (I'll look into that case now...)

Or am I on the wrong track here?

I'll just say this---not many ppl do fewest moves XD i wouldn't know what track you're on sry
lol, here to help ^_~
Sharkretriver

Posts: 367
Joined: Thu Jul 14, 2011 10:11 pm

Re: Insertions

Here's an example (It's round 361 on http://fmc.mustcube.net/)

Pre-scramble: L D' L2 U'
Scramble: R2 B D B2 D U B F2 R' B L2 U' F2 B R D2 B' R2 D B2 D2 B' U D' L R' B' D' B2 L2

Solution 1 (35 moves):

1) Build a 2x2x2 block: U' L' D'
2) Extend to 2x2x3 block: F' U L' U' L'
3) Add another 2x2 block: F L' U L
4) Orient edges: F' U' F' U
5) Place edges: F2 L F L' F

At this point, I have 25 moves (including pre-scramble).
To solve the rest, I need 10 moves to

6) ...cycle the corners into place: R B' U2 B R' B' R U2 R' B

Cycling three corners can often be done in 8 moves. So if I tracked the three corners while "unsolving" the cube, I might find a situation where this can be done.
I found this pretty hard, but after step 4) there is a situation where I can cycle them in 9 moves: L2 B' L F2 L' B L F2 L

Note that the first move in this insertion L2, together with the last move of step 4), which is L, becomes L' which saves me another turn. This way I managed to shave a couple of tuns on my solution.
Maybe not so impressive, but it was a revelation for me...

Solution 2 (33 moves):

Pre-scramble: L D' L2 U'
2x2x2: U' L' D'
2x2x3: F' U L' U' L'
+2x2: F L' U L'
Insertion: B' L F2 L' B L F2 L
Orient Edges: F' U' F' U
Finish: F2 L F L' F!!!

(BTW, Mirek Goljan found a 21 move solution to the same scramble, well done!)
arenol

Posts: 9
Joined: Sun Jul 10, 2011 9:47 pm

Re: Insertions

Congrats, just keep working at it! Also, I have no idea how to even build blocks and all that so I can't really say anything else
lol, here to help ^_~
Sharkretriver

Posts: 367
Joined: Thu Jul 14, 2011 10:11 pm