CFOP

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CFOP Method
Fridrich method.gif
Information about the method
Proposer(s): David Singmaster
René Schoof
Jessica Fridrich
Hans Dockhorn
Anneke Treep
Proposed: 1981
Alt Names: Fridrich Method
Variants: CLL/ELL, VH, ZB, MGLS-F
No. Steps: 4 (Cross, F2L, OLL, PLL)
No. Algs: Total: 78 to 119
F2L: 0 to 41
LL: 78 (OLL: 57, PLL: 21)
Avg Moves: 55
Purpose(s):
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Scrambled cube -> Cross -> F2L -> OLL -> PLL -> Solved cube


CFOP is the most frequently used speedsolving method for the 3x3x3 cube.

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CFOP (Cross, F2L, OLL, PLL, pronounced C-F-O-P or C-fop) is a 3x3 speedsolving method proposed by several cubers around 1981. It is also known as the Fridrich Method after its popularizer, Jessica Fridrich. In part due to Fridrich's publication of the method on her website in 1995, CFOP has been the most dominant 3x3 speedcubing method since around 2000, with it and its variants used by the vast majority of the top speedcubers.

Origin and Naming Dispute

Jessica Fridrich is often erroneously credited as the sole inventor of CFOP. In reality, many developments were made in the early '80s by other cubers who have contributed to the method in its current form. The constituent techniques and their original proposers are as follows:

During the resurgence in speedcubing's popularity in the late '90s and early 2000s, there was a general lack of information on the sport. Fridrich's website offered a vast wealth of information for those entering the sport, including a full description of CFOP with complete lists of algorithms. As a result, many who learned from her website began to call this method the "Fridrich Method," which explains the common use of the term today.

Several high-profile cubers have long disputed this terminology; Ron van Bruchem, famously, has publicly written that he will never call CFOP the "Fridrich Method." This issue has become well-advertised within the cubing community around the year 2008, likely because of this. The term "CFOP" has since seen increasing usage compared to back then, also in part motivated by efforts to standardize terminology in method classification, and is now seen, commonly, as "Fridrich Method."

While some cubers still insist on the term "CFOP," Fridrich's contribution to the popularization of the method is undeniable, and many others accept the term "Fridrich Method" as established terminology and a perfectly valid synonym for "CFOP."

The Steps

CFOP can be viewed as an advanced version of a Layer-By-Layer method. In particular, it combines some steps of the said method into one by using many more algorithms. Here, we outline pure CFOP without any additional trick. Also, the cube is commonly solved with the white side on top for the cross, yellow on bottom for the cross, and opposite for the other steps. However, it is NOT required.


Cross Cross


Make a cross on one side by solving all edges of a given color. Align the edges with the second-layer centers.

F2L F2L (First Two Layers)


Fill in the four slots between the cross pieces, one slot at a time. Each slot is filled by inserting a corner and its corresponding edge simultaneously. Most of the 41 cases have reasonable intuitive solutions. The completion of this step leaves one with just the last layer, typically placed on top.

OLL OLL (Orientation of the Last Layer)


Make the entire top side (the last layer) of the cube a solid color. 57 nontrivial cases.

Those new to OLL break up the step into two. This greatly reduces the number of cases; 2-look OLL has 9 cases.

PLL PLL (Permutation of the Last Layer)


Finally, you finish the cube by permuting the top layer of the cube. 21 nontrivial cases.

Those new to PLL break up the step into two. This greatly reduces the number of cases; 2-look PLL has 6 cases.

Pros

This method is relatively easy to understand when compared to other methods. Therefore, it is the most tested and most popular method used. It has a reasonable number of algorithms to learn, and sub 15 second averages are definitely possible. This method has been used to set many world records. It takes less thinking than block-building methods because it's more algorithm based.

Cons

  • Algs - CFOP has 57 OLLs and 21 PLLs for a total of 78 algs at least, and 119 algs if you learn all 41 F2L algorithms. To put that into perspective, if you took 2 days to learn each algorithm, it would take from 156 to 238 days, or 3 days each which would take from 234 to 357 days.
  • Move count - CFOP has a slightly higher average movecount that ZZ and much higher movecount compared to Roux.
  • Reliance on Inspection - CFOP makes heavy use of inspection time, which is fine when 15 seconds is given, but in situations where no inspection is used it can be a drawback. For example, when using reduction on big cubes or within multi-solve scenarios starting a CFOP solve can be difficult.
  • Difficulty of Transition from ZZ or Roux - Solving Cross and a slot-based F2L is very different from ZZf2l and Roux blocks. The possibility of using cross and a slot-based F2L can make it difficult to shake off old habits.
  • Difficulty of Cross - Cross is difficult to plan and execute in one step and takes a long time to master. New users should expect it to take in the order of years to achieve full Cross inspection in 15 seconds.
  • 2 Extra Cross Cubies to Solve - The first step of Fridrich (Cross) and ZZ (EOLine) are roughly comparable in terms of move-count. However, during cross, 2 extra cross pieces have to be solved when planning. This can make it more difficult to plan out for difficult scrambles.

See also


F2L

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OLL

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PLL

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Permutations of edges only:

Permutations of corners only:

Permutations of corners and edges:

External links