https://www.speedsolving.com/wiki/api.php?action=feedcontributions&user=CuberL&feedformat=atomSpeedsolving.com Wiki - User contributions [en]2020-08-15T06:21:17ZUser contributionsMediaWiki 1.34.0https://www.speedsolving.com/wiki/index.php?title=LLEF&diff=25772LLEF2015-02-26T10:22:37Z<p>CuberL: edit the 4-flip(A</p>
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<div>{{Substep Infobox<br />
|name=LLEF<br />
|image=LLEF.png<br />
|variants=[[ELL]], [[EOLL]], [[EPLL]]<br />
|subgroup=<br />
|algs=15<br />
|moves=7.87 (Optimal [[HTM]])<br />
|purpose=<sup></sup><br />
* [[Speedsolving]], [[FMC]]<br />
|previous=[[F2L cube state]]<br />
|next=[[LL:EO+EP cube state]]<br />
}}<br />
<br />
'''LLEF''' (Last Layer Edges First) is a variation of [[ELL]] (Edges of the Last Layer) that ignores corners is easier to solve; it uses both fewer moves and has fewer cases than what is the '[[ELL|normal ELL]]'. This variation is useful for a 2-look method that solves corners last (see [[L4C]]). But L4C is not in use for speed solving, because of two reasons, it has twice the number of cases of [[CLL]] and the [[algorithm]]s that solve them are mostly long (the worst LL case of all is in this group, it needs 16 turns optimally ([[HTM]])). Another backdraw is that recognition for solving the edges before the corners is not so easy. If you don't have a system for colour recognition you have to [[AUF]] to have a chance, sometimes even repeated AUFs.<br />
<br />
LLEF can also be useful for a [[3LLL]] method known as [[BLL]]. This method has a total of 24 algorithms and an average total of 27 moves.<br />
<br />
It can however be useful for [[FMC]]. LLEF has a low average optimal solution length of 7.87, while for the last four corners it is 11.73 (a half move more than optimal [[PLL]]). Both of these can however be lowered. One can quite often choose a inversion/mirror version of an alg to solve the same LLEF situation thus increasing one's chances of cancelling moves and/or getting a better corner case. [[Partial Edge Control|Partial edge control]] can also be used to avoid the cases with four flipped edges. The corners can in turn be solved more efficiently with inserted corner 3-cycles rather than at the very end of the solution.<br />
<br />
Solving ELL first is 15 cases from a group of totally 48, i.e. a skip of this step occures 1:48 times, skip to [[EP]] only occures 1:8 times and skip to pure [[EO]] occures 1:6 times.<br />
<br />
===See also===<br />
* [[ELL]]<br />
* [[FMC]]<br />
<br />
== External links ==<br />
* [http://www.ai.univ-paris8.fr/~bh/cube/ Bernard Helmstetter's LL algorithms]<br />
* [http://emsee.110mb.com/Speedcubing/ZZLL/No%20parity.html Michal Hordecki's algorithms for the last 4 corners]<br />
<br />
==Algorithms==<br />
{{Algnote}}<br />
<br />
The images have corners solved in darker colours, this works as a guide for those who don't know the colour sheme or is using something diffrent from this. For all other reasons you can ignore the corners.<br />
<br />
The first alg given for each case is the optimal solution in [[HTM|Half Turn Metric]].<br />
<br />
==All edges oriented (EP) ==<br />
{|border="0" width="100%" valign="top" cellpadding="3"<br />
<br />
|-valign="top"<br />
|<br />
=== Adjacent swap (Sune) ===<br />
[[File:LLE OA.jpg]]<br />
<br />
{{Alg|(y') R' U2 R U R' U R}}<br />
<br />
|<br />
<br />
=== Opposite swap (T-PLL) ===<br />
[[File:LLE OO.jpg]]<br />
<br />
{{Alg|R' F R' u2 R F' R' u2 R2 F'}}<br />
{{Alg|R2 u R2 u' R2 y' R2 u' R2 u R2}}<br />
<br />
|}<br />
<br />
==Pure flips (EO) ==<br />
<br />
{|border="0" width="100%" valign="top" cellpadding="3"<br />
<br />
|-valign="top"<br />
|<br />
=== 2-flip (Adjacent) ===<br />
[[File:LLE 2AP.jpg]]<br />
<br />
{{Alg|R' U' R2 B' R' B2 U' B'}}<br />
<br />
|<br />
<br />
=== 2-flip (Opposite) ===<br />
[[File:LLE 2OP.jpg]]<br />
<br />
{{Alg|(y) R B L' B L B' U B' U' R'}}<br />
<br />
|-valign="top"<br />
|<br />
<br />
=== 4-flip ===<br />
[[File:LLE 4P.jpg]]<br />
<br />
{{Alg|R2 L' B R' B L U2 L' B R' L}}<br />
<br />
|<br />
|}<br />
<br />
==Adjacent swap==<br />
<br />
{|border="0" width="100%" valign="top" cellpadding="3"<br />
<br />
|-valign="top"<br />
|<br />
=== Adjacent RF ===<br />
[[File:LLE ASFR.jpg]]<br />
<br />
{{Alg|(y2) R2 L' B R' B R B2 R' B R' L}}<br />
<br />
|<br />
<br />
=== Adjacent FL ===<br />
[[File:LLE ASLF.jpg]]<br />
<br />
{{Alg|F U R U' R' F'}}<br />
<br />
|-valign="top"<br />
|<br />
<br />
=== Adjacent LB ===<br />
[[File:LLE ASBL.jpg]]<br />
<br />
{{Alg|(y) L' B' R B' R' B2 L}}<br />
{{Alg|r U R' U R U2 r' U'}}<br />
{{Alg|y r U2 R' U' R U' r' U}}<br />
{{Alg|M U M' U2 M U M' U'}}<br />
<br />
|<br />
<br />
=== Adjacent BR ===<br />
[[File:LLE ASRB.jpg]]<br />
<br />
{{Alg|(y') B' U' R' U R B}}<br />
<br />
|-valign="top"<br />
|<br />
<br />
=== Opposite RF ===<br />
[[File:LLE ASOF.jpg]]<br />
<br />
{{Alg|(y2) F R U R' U' F'}}<br />
{{Alg|r U L' U' r' U L U' (x) U}}<br />
<br />
|<br />
<br />
=== Opposite BR ===<br />
[[File:LLE ASOB.jpg]]<br />
<br />
{{Alg|F' L' U' L U F}}<br />
<br />
|-valign="top"<br />
|<br />
<br />
=== 4-flip (A4) ===<br />
[[File:LLE AS4.jpg]]<br />
<br />
{{Alg|(y) B L U L' U B' U2 B' R B R'}}<br />
<br />
|<br />
|}<br />
<br />
==Opposite swap==<br />
<br />
{|border="0" width="100%" valign="top" cellpadding="3"<br />
<br />
|-valign="top"<br />
|<br />
=== Adjacent (OA) ===<br />
[[File:LLE OSA.jpg]]<br />
<br />
{{Alg|(y2) B' R' U R B L U' L'}}<br />
<br />
|<br />
<br />
=== Opposite (OO) ===<br />
[[File:LLE OSO.jpg]]<br />
<br />
{{Alg|B' R' U R B L' B L B2 U B}}<br />
<br />
|-valign="top"<br />
|<br />
<br />
=== 4-flip (O4) ===<br />
[[File:LLE OS4.jpg]]<br />
<br />
{{Alg|R B' R' B U B2 L' B' L U' B'}}<br />
<br />
|<br />
|}<br />
<br />
[[Category:Acronyms]]<br />
[[Category:3x3x3 last layer substeps]]<br />
[[Category:Algorithms]]<br />
<br />
__NOTOC__</div>CuberL