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Speedcubing (also known as speedsolving) is the activity of solving a variety of twisty puzzles, the most famous being the Rubik's Cube, as quickly as possible. For most puzzles, solving entails performing a series of moves that alters a scrambled puzzle into a state in which every face of the puzzle is a single, solid color. Some puzzles have different requirements to be considered solved, such as the Clock, for which all the dials must be moved into the 12 'o clock position.
Contents
- History
- Solving methods
- CFOP method
- Roux method
- ZZ method
- Petrus method
- Corners first methods
- World Cube Association
- Format
- World Rubiks Cube Championships
- World records
- Lubrication
- Terminology
- References
Most cubes are sold commercially in variations of 2×2×2, 3×3×3, 4×4×4, 5×5×5, 6×6×6, and 7×7×7, although variations of the puzzle have been designed with as many as 22 layers, although not mass produced for the public. The current record for a single solve is held by Feliks Zemdegs, who presented a 4.73 second solve at the POPS Open 2016 in December 2016. Feliks Zemdegs also holds the world record for the average of five solves at 6.45 seconds, which he set in July 2016 at the WLS Lato 2016 competition.
Speedcubing is a popular activity among the international Rubik's Cube community, or cubers. Members come together to hold competitions, work to develop new solving methods, and seek to perfect their technique.
History
The Rubik's Cube was invented in 1974 by Hungarian professor of architecture, Ernő Rubik. A widespread international interest in the cube began in 1980, which soon developed into a global craze. On June 5, 1982, the first world championship was held in Budapest, Hungary. 19 people competed in the event and the American Minh Thai won with a single solve time of 22.95 seconds. Other notable attendees include Jessica Fridrich and Lars Petrus, two people who would later be influential in the development of solving methods and the speedcubing community. The height of the Rubik's Cube craze began to fade away after 1983, but with the advent of the Internet, sites relating to speedcubing began to surface. Simultaneously spreading effective speedsolving methods and teaching people new to the cube to solve it for the first time, these sites brought in a new generation of cubers, created a growing international online community, and raised the profile of the art. People prominent in this online community, such as Ron Van Bruchem, Tyson Mao, Chris Hardwick, and Ton Dennenbroek, eventually wanted to meet in person and compete, so twenty years after the first world championship they orchestrated a second one in Toronto in 2003, and another smaller competition in the Netherlands later that same year. This revival of competition sparked a new wave of organized speedcubing events, which include regular national and international competitions. There were twelve competitions in 2004, 58 more from 2005 to 2006, over 100 in 2008, and over 450 in 2014, with more happening every year. There have been seven more World Championships since Budapest's 1982 competition, which are traditionally held every other year, with the most recent in São Paulo, Brazil, in 2015. This new wave of speedcubing competitions have been and still are organised by the World Cube Association (WCA), founded by Ron van Bruchem.
Solving methods
The standard Rubik's Cube can be solved using a number of methods, not all of which are intended for speedcubing. Although some methods employ a layer-by-layer system and algorithms, other significant (though less widely used) methods include corners-first methods, and the Roux method. CFOP, Roux, ZZ, and Petrus are often referred to as the "big four" methods, as they are the most popular and can be used to achieve faster times than the others. The CFOP method is considered the fastest method currently as it is has been used to set the fastest times.
CFOP method
The CFOP (Cross - F2L - OLL - PLL) method, also known as the Fridrich Method, was named after one of its inventors, Jessica Fridrich, who finished second in the 2003 Rubik's Cube World Championships. While it is known as the Fridrich method, its origins are actually credited to David Singmaster, who was one of the first to publish a layer by layer method of solving in 1980, and Guus Razoux Schultz, who built upon this and developed a more efficient system for the first two layers (F2L). Jessica Fridrich then finished developing the method and published it online in 1997, an event that was very influential in the revival of competitive speedcubing. The first step of the method is to solve a cross-shaped arrangement of edge pieces on the first layer. The remainder of the first layer and all of the second layer are then solved together in what are referred to as "corner-edge pairs" or slots. Finally, the last layer is solved in two steps — first, all of the pieces in the layer are oriented to form a solid color (but without the individual pieces always being in their correct places on the cube). This step is referred to as orientation and is usually performed with a single set of algorithms known as OLL (Orientation of Last Layer). Then, all of those pieces are permuted to their correct spots. This is also usually performed as a single set of algorithms known as PLL (Permutation of Last Layer).
The CFOP method can be used as a less-advanced method by dividing the steps into more steps, reducing the number of algorithms you need to learn but sacrifices time. Most people start learning CFOP with 4LLL (Four-look last layer), which is the less advanced, slower, and algorithm-reducing way to learn CFOP. The 4 steps are divided into Edge Orientation, Corner Orientation, Corner Permutation, and Edge Permutation. Later on, you can learn Full PLL which replaces the permutation of the edges and corners, making the solve more efficient and therefore faster. Even later, you can learn Full OLL which will replace the Orientation of the corners and edges, again making the solve faster.
The CFOP method is a widely used speedcubing method. Its popularity stems from the speed at which it can be easily performed. Many advanced speedcubers have also learned additional sets of algorithms for the last layer, such as Corners of Last Layer (COLL), which orients and permutes the corners when the edges are oriented.
Roux method
The Roux method was invented by French speedcuber Gilles Roux. The first step of the Roux method is to form a 3×2×1 block usually placed in the lower portion of the left layer. The second step is to create another 3×2×1 on the opposite side, such that each block is sharing a bottom color. The remaining four corners are then solved using a set of algorithms known as CMLL (Corners of the Last Layer, without regard to the M-slice), which leaves six edges and four centers that are solved in the last step, L6E or LSE (Last Six Edges).
This method is not as dependent on algorithm memorization as the CFOP method, since all but the third step is done with intuition as opposed to predefined sets of algorithms. The Roux method can be performed without rotations (unlike the CFOP method) which means it is easier to look ahead (solving a collection of pieces while at the same time looking for the solution to the next step) while solving.
ZZ method
The ZZ method, short for Zbigniew Zborowski, is a modern speedcubing method originally proposed by Zbigniew Zborowski in 2006. The method was designed specifically to achieve high turning speed by focusing on move ergonomics, and is the combination of a block-building method and a layer-by-layer method. The initial pre-planned step is called EOLine, and is the most distinctive hallmark of the ZZ method. It involves orienting all edges while placing two oppositely placed down-face edges aligned with the correspondingly colored center. The next step solves the remaining first two layers using only left, right, top and bottom face turns, one of the advantages of ZZ. On completion of the first two layers, the last layer's edges are all correctly oriented because of edge pre-orientation during EOLine. The last layer may be completed using a number of techniques including those used in the CFOP method. An expert variant of this method (ZZ-a) allows the last layer to be completed in a single step with an average of just over 12 moves and knowledge of at least 472 algorithms.
Petrus method
The Petrus method, named after its inventor Lars Petrus, is considered to be more intuitive than the structured CFOP method. The first step of the Petrus method is to solve a 2×2×2 block of the cube. This block is then extended to a solved 2×2×3 block. All edges that are unoriented are then oriented, and then the first and second layers are completed using only turns of the right layer and the upper layer. Next, the top corners are put in the right place and the layer is oriented correctly (all stickers facing up) and finally the last edges are permuted (moved around). Lars Petrus developed this method to address what he felt were inherent inefficiencies in layer-by-layer approaches. This method is often used as the basis of a method for fewest moves competitions.
Corners-first methods
Corners-first methods involve solving the corners then finishing the edges with slice turns. Corners-first solutions were common in the 1980s, and was one of the most popular methods that 1982 world champion Minh Thai used. Currently corners-first solutions are less common among speedsolvers. Dutch cuber Marc Waterman created a corners-first method in the cube craze, and averaged 18 seconds in the mid-late 1980s.
World Cube Association
Since 2003, speedcubing competitions have been held regularly. The World Cube Association (WCA) was formed in 2004 to govern all official competitions. For a competition to be official, it must be approved by the WCA and follow the WCA regulations. Included in the regulations is the necessity of having one or more WCA delegate in attendance. A delegate's main role is to ensure all regulations are followed during the competition. Once the competition has finished, the results are uploaded on to the WCA website.
Format
The majority of puzzle competitions are held using an average of 5 format. This involves the competitor solving 5 times in the round; the fastest and slowest solve are disregarded and the mean of the remaining 3 is used. The 6×6×6, 7×7×7 and solving-with-the-feet events are ranked by mean of 3. This is the same but only three solves are done, and no solves are disregarded when calculating the mean. 3×3×3 blindfolded and fewest moves challenge are held either by mean of 3 or best of 3. 4×4×4 blindfolded, 5×5×5 blindfolded and multiple blindfolded are held using best of 1, 2 or 3, depending on the competition. Occasionally an event is held using an uncommon format, for example best of 3 for 3×3×3.
When a round begins, competitors hand in the puzzle they will use. Puzzles are scrambled using a computer-generated scramble. Each round, five, three or one (depending on the format, mentioned above) scrambles are used. Every competitor in the round will receive each scramble once. Before starting a solve, a competitor has up to 15 seconds to inspect the puzzle (inspection is removed for blindfolded events). This is monitored by a judge with a stopwatch. Once the solve is complete, the judge records the time on the competitor's scorecard and it is signed by both. If the puzzle is unsolved and the timer is stopped, the time is recorded as "DNF" (did not finish). There are also numerous reasons why the solve can receive a two-second addition to the solve time, such as a face being more than 45 degrees off, or the competitor going over the allowed inspection time. A competitor can also receive an extra solve to replace the one just completed, for example having a timer malfunction or being deliberately distracted by another person.
Currently, the official timer used in competitions is the StackMat timer. This device has touch-sensitive pads that are triggered by the user lifting one or both of their hands to start the time and placing both their hands back on the pads after releasing the puzzle to stop the timer.
Official competitions are currently being held in several categories.
Competitions will often include events for speedsolving these other puzzles, as well:
World Rubik's Cube Championships
The WCA organizes the World Rubik's Cube Championship as the main international competition once every two years. The latest championship was held in São Paulo, Brazil, from July 17–19, 2015. The next championship will be held in Paris, France, in July 2017.
World records
The following are the official speedcubing world records that are approved by the World Cube Association.
Note: For averages of 5 solves, the best time and the worst time are dropped, and the mean of the remaining 3 solves is taken. When only 3 solves are done, the mean of all 3 is taken as normal.
Lubrication
Members of the cubing community lubricate their cubes to allow them to be manipulated faster, easier, and more reliably than a non-lubricated cube. The WCA allows lubrication for official competitions.
Popular lubricants among speedcubers are:
Checking a lubricant's MSDS is often helpful in identifying cube-damaging ingredients.
Terminology
Below are some definitions of words generally used by the speedcubing community. For a more complete list of speedcubing terminology, see the cubefreak.net glossary.