# FMC riddle: second layer edge



## Stefan (Oct 20, 2011)

Scramble 1: F' U' F U R U R' U
Scramble 2: F' U' F U R U R' U'

Solve F2L in seven turns (htm). There are several interesting different ways, how many can you find? No cheating with computer solvers!

Hints (first move of each solution):


Spoiler



Scramble 1:
F ...
F' ...
B ...
B ...
B' ...
B' ...

Scramble 2:
R' ...
F ...
L ...
B ...



Just so you know when you're done:
6 solutions for F' U' F U R U R' U
4 solutions for F' U' F U R U R' U'

Also:
3 solutions for F' U' F U R U R' U2
7 solutions for F' U' F U R U R' (including one or two you probably didn't know yet)

Solutions (check these out when you're done or give up, many are quite neat):


Spoiler



Scramble F' U' F U R U R' U:
F U2 L F2 L' U2 F'
F' U2 L' U2 L U2 F
B U B2 D' R2 D B
B L2 D F2 D' L2 B'
B' R2 U' R2 U R2 B
B' D' R2 D B2 U' B'

Scramble F' U' F U R U R' U':
R' U2 B' R B U2 R
F U2 L F L' U2 F'
L F2 U F U' F2 L'
B L2 D F D' L2 B'

Scramble F' U' F U R U R' U2:
R U2 R' U2 F' U' F
R U2 B U' B' U2 R'
L F2 U F' U' F2 L'

Scramble F' U' F U R U R':
R U R' U' F' U' F
R U' R' U2 F' U2 F
R U' R' U' F' U F
R U' R' F R' F' R
F R' F' R F' U' F
F' U2 L' U' L U2 F
B L2 D F' D' L2 B'


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## Sa967St (Oct 20, 2011)

got one:


Spoiler



U' R U' R' U' F' U x


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## jms_gears1 (Oct 20, 2011)

Spoiler



y R' u' R2 u R2 U' R'


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## Stefan (Oct 20, 2011)

(Note: I added a second riddle and hints)

Ah yes Sarah, the cheating one . I thought about that but didn't include it in my spoiler because I wasn't sure it's the only one and I wanted either all or none.


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## macky (Oct 20, 2011)

stuck at two


Spoiler



yR'D'F2DR2U'R'
yR'F2U'F2UF2R


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## AustinReed (Oct 20, 2011)

Spoiler



F' U2 L' U2 L U2 F


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## Sa967St (Oct 20, 2011)

Stefan said:


> (Note: I added a second riddle and hints)
> 
> Ah yes Sarah, the cheating one . I thought about that but didn't include it in my spoiler because I wasn't sure it's the only one and I wanted either all or none.


Well, it's an F2L somewhere. 
I didn't even realize it was the inverse at first.


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## Julian (Oct 20, 2011)

First one:


Spoiler



B' R2 U' R2 U R2 B



Let me try and find more.


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## jms_gears1 (Oct 20, 2011)

Second one:


Spoiler



R'U2B'RBU2R
LF2UFU'F2L'


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## mr. giggums (Oct 20, 2011)

Spoiler



Scramble 1:
F U2 L F2 L' U2 F'
F' U2 L' U2 L U2 F
B L2 D F2 D' L2 B'
B U B2 D' R2 D B
B' D' R2 D B2 U' B'
B' R2 U' R2 U R2 B

Scramble 2:
R' U2 B' R B U2 R
F U2 L F L' U2 F'
L F2 U F U' F2 L'
B L2 D F D' L2 B'


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## Stefan (Oct 20, 2011)

mr. giggums: so close...

Btw, I of course did use a computer solver, I was looking for something else and was surprised how many different solutions there were so I made this thread. Makes a nice riddle and training, and maybe it can be useful for FMC.


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## DavidWoner (Oct 20, 2011)

Grrrrrrr can't find the last one for scramble 1. Got all the rest though. 

Edit: GOT IT! So weird how that last one works. anyway what do I win?



Spoiler



Scramble 1: F' U' F U R U R' U

U' R U' R' U' F' U
F' U2 L' U2 L U2 F
B' D' R2 D B2 U' B'
F U2 L F2 L' U2 F'
B' R2 U' R2 U R2 B
B L2 D F2 D' L2 B'
B U B2 D' R2 D B
Scramble 2: F' U' F U R U R' U'

U R U' R' U' F' U
R' U2 B' R B U2 R
F U2 L F L' U2 F'
L F2 U F U' F2 L'
B L2 D F D' L2 B'



Of course this one is the best F2L for FMC, but I know that it's not what you're going for:



Spoiler



For #1: U' R
For #2: U R


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## mrCage (Oct 20, 2011)

Cool riddle. but not useful for normal fmc. Since the solution is not allowed to be related to the scramble ... Backwards solution (wrt scramble) is STRICTLY related to the scramble. Oh well


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## mrCage (Oct 20, 2011)

David, your 2-turn solutions only give pseudo f2l. But indeed useful for fmc yes!!

Per


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## Cubenovice (Oct 20, 2011)

Just basing myself on the description (without applying or analyzing the scramble) I propose:

EDIT: I'm stupid...


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## Stefan (Oct 20, 2011)

DavidWoner said:


> anyway what do I win?



My appreciation 

Hmm, I guess I should've posted the number of solutions outside that spoiler, otherwise people see the starts when just looking for whether they found all solutions.

6 solutions for F' U' F U R U R' U
4 solutions for F' U' F U R U R' U'
3 solutions for F' U' F U R U R' U2
7 solutions for F' U' F U R U R' (including one or two you probably didn't know yet)



DavidWoner said:


> So weird how that last one works





Spoiler



Yeah, it's magic. And the inverse of another. That's what I meant with "mr. giggums: so close", cause his missing one is pretty much right next to it.





mrCage said:


> not useful for normal fmc. Since the solution is not allowed to be related to the scramble


 
No idea what you're talking about. How is knowing more algs/tricks not useful for fmc, and how is it related to the scramble??


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## mrCage (Oct 20, 2011)

Sorry, i was unclear in my first post. Simply inversing the scramble from last to 2nd move is definitely cheating by all standards. Finding other solutions is indeed interesting. I'd guess most solutions would be known for experienced fridrich solvers??

Per


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## mr. giggums (Oct 20, 2011)

Just finished mine. I didn't look at David's spoiler until after I finished. The one I got stuck on was the B U B2 ...


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## Stefan (Oct 20, 2011)

mrCage said:


> I'd guess most solutions would be known for experienced fridrich solvers??


 
Maybe I'm just not experienced enough, but for the scrambles ending in U, U' and U2 I didn't know *any* of the 13 solutions (maybe I should know at least the one jms_gears1 posted and its inverse, cause they're fast). For the one ending without U-turn, I "knew" five of the seven solutions.


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## Stefan (Oct 20, 2011)

I've included the solutions in the [post=657234]first post[/post] now with alg.garron for easy viewing.


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## DavidWoner (Oct 20, 2011)

Stefan said:


> 3 solutions for F' U' F U R U R' U2
> 7 solutions for F' U' F U R U R' (including one or two you probably didn't know yet)


 
Haven't had a go at these yet, I'll try now



Spoiler



scramble: F' U' F U R U R' U2
L F2 U F' U' F2 L'

Scramble: F' U' F U R U R'
B L2 D F' D' L2 B'
R U' R' U' F' U F obviously
R U' R' F R' F' R also obvious



Ehh cba to find the rest right now, I'll do it later.


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## mr. giggums (Oct 20, 2011)

Without looking at stefan's spoiler



Spoiler



Scramble 3: (U2 AUF)
R U2 R' U2 F' U' F
(B' D' F' U F E' R )

Scramble 4: (no AUF)
R U' R' U' F' U F
R U' R' U2 F' U2 F
R U' R' F R' F' R
R U R' U' F' U' F
F' U2 L' U' L U2 F
B L2 D F' D' L2 B'


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## teller (Oct 21, 2011)

Unless I'm misunderstanding the rules, you are missing the ones I actually use for these: 



Spoiler



Scramble 1: R S' R' U' R S R'
Scramble 2: R S' R' U R' S' R'


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## mr. giggums (Oct 21, 2011)

teller said:


> Unless I'm misunderstanding the rules, you are missing the ones I actually use for these:
> 
> 
> 
> ...


 
This is FMC though so slice moves count as 2 moves.


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## teller (Oct 21, 2011)

mr. giggums said:


> This is FMC though so slice moves count as 2 moves.


 
Ah, that would explain it. Thanks!


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## Stefan (Oct 21, 2011)

No, FMC isn't always HTM, here you can even choose between four metrics including STM:
http://fmc.mustcube.net/results.php

But I asked for HTM in the first post.


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## mrCage (Oct 21, 2011)

Stefan said:


> No, FMC isn't always HTM, here you can even choose between four metrics including STM:
> http://fmc.mustcube.net/results.php
> 
> But I asked for HTM in the first post.


 
He is kind of correct! In offline competitions (WCA ones) fewest moves is always counted wrt htm 
The thinkgs that have changed in WCA fewest moves competitions is the number of rounds and the time allowed. It always was and still is counted in htm, IMHO the best metric 

Per

PS! To be more precise: fewest moves and fmc are not entirely the same thing. Fmc is an online competition started by Dan Harris, UK. Later continued by me on my own website. FMC and (WCA) fewest moves have different sets of regulations. Etc ...

Check fmc.mustcube.net and wca fewest moves regulations ...

Per


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## RCTACameron (Oct 21, 2011)

Spoiler



First scramble:
B' D' R2 D B2 U' B'
F U2 L F2 L' U2 F'
Second scramble: 
F U2 L F L' U2 F'


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## cunningcuber (Nov 1, 2011)

this is actually quite interesting. You should do this weekly or something


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## Tao Yu (Nov 1, 2011)

Got both of them!(and two solutions for F' U' F U R U R' U2) 


Spoiler



*1st one*
F'U2L'U2LU2F
and B'R2U'R2UR2B
*2nd one*
LF2UFU'F2L'

* F' U' F U R U R' U2*
U2BU'B'U2R'
and RU2R'U2F'U'F


Yes!
Its so annoying getting 8 movers over and over again.


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## Cielo (Nov 7, 2011)

Scramble 1: F' U' F U R U R' U (1 to go with the help of hint)


Spoiler



F U2 L F2 L' U2 F'
B' R2 U' R2 U R2 B
F' U2 L' U2 L U2 F
B L2 D F2 D' L2 B'
(with the hint) B' D' R2 D B2 U' B'


Scramble 2: F' U' F U R U R' U' (done with the help of hint)


Spoiler



L F2 U F U' F2 L'
B L2 D F D' L2 B'
F U2 L F L' U2 F'
(with the hint) R' U2 B' R B U2 R


Scramble 3: F' U' F U R U R' U2 (done)


Spoiler



L F2 U F' U' F2 L'
R U2 R' U2 F' U' F
R U2 B U' B' U2 R'


Scramble 4: F' U' F U R U R' (done)


Spoiler



R U' R' U' F' U F
R U' R' F R' F' R
R U R' U' F' U' F
F' U2 L' U' L U2 F
F R' F' R F' U' F
B L2 D F' D' L2 B'
R U' R' U2 F' U2 F (nearly missed this one...)


After seeing the hints, I still can't find this one.


Spoiler



B U B2 D' R2 D B
And I didn't realize it's just the inverse of another solution at the first glance.


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