Fridrich Method

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Fridrich Method is one of the most commonly used methods in speedsolving a Rubik's Cube. This method was first developed in the early 1980s by Jessica Fridrich, and was published online in 1997. ^[1]

The method works on a layer-by-layer system, first "solving" a cross on the bottom, continuing to solve the first two layers (F2L), orienting the last layer (OLL), and finally permuting the last layer (PLL). This method is commonly referred to as CFOP (Cross, First 2 Layers, Orient Last Layer, Permute Last Layer).

Contents 1 The method 2 Tournament use 3 External links 4 References

[edit] The method

The method consists of 4 steps:

• The Cross - This first stage involves solving four edge pieces on one side. By convention, the side most widely used by speedcubers is white. This step is the most intuitive step of the solve but it is also very fast; Experienced speedcubers can solve it in about 2-3 seconds, and in all cases it requires less than 9 turns to solve.

• First Two Layers (F2L) - After the Cross is completed, the entire first two layers are solved in this step. This is done by inserting 4 corner & edge pairs into each one of the 4 'slots', one by one. This step can be done intuitively because the entire last layer is still unsolved and it can therefore be used as a convenient workspace. Each corner/edge pair is usually connected in the last layer and then inserted into it's proper position. Many speedcubers choose to learn a few F2L algorithms for some obscure cases that are generally long to solve intuitively.

• Orientation of Last Layer (OLL) - This stage involves manipulating the top layer so that all 9 cubies on the top side are the same color, even at the expense of incorrect colors on other sides. This stage involves learning a total of 57 algorithms.

• Permutation of last layer (PLL) - the final stage involves moving the pieces of the top layer while preserving their orientation. There are a total of 21 algorithms for this stage.

[edit] Tournament use

The Fridrich method is used by many competitors both due to its speed and versatility. With a couple of extending modifications, particularly in the F2L part of the solution, it is good enough to achieve averages in low teens.

[edit] External links

• Jessica Fridrich's official site
• Description of the Fridrich Method
• Cubewhiz List of OLL and PLL algorithms
• Cubezone List of OLL and PLL algorithms
• Joel's List of OLL and PLL algorithms

[edit] References

v • d • e Rubik's Cube Inventor Ernő Rubik Rubik's Cubes Overview • 2×2×2 (Pocket Cube) • 3×3×3 (Rubik's Cube) • 4×4×4 (Rubik's Revenge) • 5x5x5 (Professor's Cube) Cubic variations Square 1 • Skewb • Sudokube Non-cubic variations Megaminx • Pyramorphix • Pyraminx • Skewb Diamond • Skewb Ultimate • Dogic • Alexander's Star Derivatives Rubik's Magic • Rubik's Snake • Missing Link • Rubik's Revolution • Rubik's Clock World record holders Yu Nakajima Renowned Solvers Jessica Fridrich • Lars Petrus • Ron van Bruchem • Chris Hardwick • Shotaro "Macky" Makisumi • Tyson Mao • Leyan Lo Solutions God's algorithm • Optimal • Speedcubing Mathematics Rubik's Cube group Related Articles List of Rubik's Cube software