Megabytes). This is probably the most obvious difficulty in solving the puzzle. Optimality of this solution
The point is that it tries to make you only need to consider no more than 30 squares involved in this step at any time in the 5 steps.
Combination mode. The first of these 20 rotatable squares 12 is located one by one, so most of the time, you
You only need to consider the position of a square.
However, as long as only so few combinations of squares are considered at a time, it is entirely possible to write them down and send them to everyone.
This situation provides a suitable rotation method. Therefore, no matter which combination, no matter whether the Rubik's cube is twisted or not.
No matter how chaotic it is, this solution can guarantee success. (Note: If you have disassembled the Rubik's Cube, please make sure it is not assembled.
Put it in the wrong place)
Right+: Rotate the right plane 90 degrees clockwise.
Right-:Rotate the right plane counterclockwise by 90 degrees.
Right 2: Rotate the right plane by 180 degrees (the clockwise and counterclockwise effects are the same at this time).
Front+: Rotate the front plane 90 degrees clockwise.
Front-:Rotate the front plane 90 degrees counterclockwise.
Front 2: Rotate the front plane by 180 degrees.
Left+: Rotate the left plane 90 degrees clockwise.
Left-:Rotate the left plane counterclockwise by 90 degrees.
Left 2: Rotate the left plane by 180 degrees.
Bottom+: Rotate the bottom plane 90 degrees clockwise.
Bottom-:Rotate the bottom plane 90 degrees counterclockwise.
Bottom 2: Rotate the bottom plane by 180 degrees.
Top+: Rotate the top plane 90 degrees clockwise.
Top-:Rotate the top plane 90 degrees clockwise.
Top 2: Rotate the top plane by 180 degrees.
first step
Step 1 Top edge (front top, left top, back top, right top)
Before solving, select the color of the top surface. Don't forget that the color of any plane is determined by the color of its central square.
It's decided. Hold the Rubik's Cube correctly so that the plane you choose faces upwards. This is the top surface, which has been completely solved.
Keep the plane unchanged during the process.
The purpose of this step is to locate and orient the squares belonging to the four edge positions of the top plane. These four top squares
Placed and oriented one by one. You should do the following five steps for each square (1A- 1e). If you're lucky.
If you are lucky, maybe one or two of the squares are in the right place, then you just need to put these five steps.
(1A- 1e) Do it two or three times. If you are still confused about this, please check the contents of the standards and terms.
1A: Hold the Rubik's Cube correctly so that there are no placed and oriented squares at the top of the front. You might want to hold the whole thing in your hand.
The Rubik's cube should do this, so that it will also change the color of the front plane.
1B: Find the square that should belong to this top. This square that requires a solution is called an on-demand square.
1C: If this box is already on the top, but the direction is wrong, please refer to1e.
1D: there are 1 1 possibilities for the position of this required square, so there are 1 1 groups of corresponding rotations here. According to this.
You need to do one of the following 1 1 group rotations at the position of the square. For example, the current position of the desired box is the upper right part.
Then it can be handled according to the rotation from the right top to the front top.
Rotation method from top right to top front: right-front-
Back top to front top rotation method: top+right-top-front-
Rotation method from top left to top front: left+front+
Front right to front top rotation method: front-
Rotation method from right rear to front top: right 2- right front 2.
Left back to front top rotation method: left 2 front+left 2.
Front Left to Front Up Rotation Method: Front+
From bottom to front: the first two
Rotation method from bottom right to top front: 2 from bottom to top.
Bottom back to front top rotation method: bottom 2 front 2
Rotation method from bottom left to top front: bottom+top 2.
1E: If the front top box is currently in the correct position but in the wrong direction, please rotate it in the following directions:
Directional rotation mode of front roof: front roof+left roof-
(These four top squares are oriented one by one, so you may need to do these five squares 1A- 1e four times.
Steps. After this step, a cross pattern will appear on the top plane (if you choose green as the top color).
A green cross will appear).
Second step
Step 2 Vertex Angle (left front top, right front top, left rear top, right rear top)
The purpose of this step is to give four corners belonging to the top surface, while keeping the top edge of the placement square.
Square positioning and position orientation. In this series of rotations, the top edge box will be temporarily moved, but this will be appropriate.
repair
The following six steps (2A-2F) are required for each of the four squares belonging to the angular position of the top surface. identical
2B: If the requested box is now on the top surface, please make the following set of rotations. Please hold the Rubik's Cube in a certain direction to make it necessary.
Party violation is at the top right.
Right front from top to bottom left front rotation method: left-down-right+
This rotation moves the required block to the bottom plane.
2C: Rotate the bottom plane so that the desired square currently on the bottom plane is weighed to the corner of the top surface it should occupy.
Just below the site (this site is called the on-demand site). Hold the Rubik's cube in a certain direction, so that the required part is the upper right of the front.
At this time, the required position is the right front top position. At this time, the required square should be in the correct position on the bottom surface.
2D: To correctly place the required corner box, please do the following rotation.
Bottom right front to right front top rotation method: right-down-right+
2E: If the front top box is in the wrong direction, do one of the following two sets of rotation (note: only do one set).
Directional rotation method of front, upper and right: lower right, 2 right+,front+lower 2 front-
Directional rotation method of front, upper right and lower right: front+lower 2 front-,right-lower 2 right+
2F: If the direction of the box in the upper right corner is still incorrect, repeat the rotation you made in 2E. This will make the front right top.
The direction and position of the block are correct.
You may need to repeat these six steps (2A-2F) four times to complete the positioning and orientation of these four corner boxes.
. After doing this, one-third of the entire Rubik's Cube, that is, all the squares on the top surface, will be in the right direction.
Please, everyone.
Third step
Middle edge (left front, right front, left rear, right rear)
The purpose of this step is to locate and orient the four edge boxes below the top plane. This step can be regarded as an "intermediate link"
Layer plane ". Once this step is completed, two-thirds of the Rubik's Cube will be completed. Because each should belong to the middle edge.
The following four steps (3A-3D) should be taken for the edge position of the box. You may find a middle border box again.
It's already in the right place.
3A: Find a middle-level edge box whose direction has not been determined (that is, the box that should belong to the middle-level edge position).
. This is an on-demand box. If the location of this demand box is correct, but the direction is wrong, please refer to 3D.
3B: If the required box is not on the bottom plane, please make the following set of rotations. Hold the Rubik's cube correctly in a certain direction, and that's right.
The box is in the front right.
Rotation method from front right to bottom plane (bottom back): right-bottom+right+bottom+front+bottom-front-
3C: At this time, the required square has reached the bottom plane. Rotate the bottom plane so that the colors of the vertical plane and the four sides of the required square are the same.
(back and forth, left and right). Then hold the Rubik's cube correctly and make it necessary.
The position is the right front position. If the required square is on the right plane at this time, make a set of rotations from the lower right to the right front. If the required square
The block is located in the front plane and rotates in groups from the bottom to the right front.
Rotation method from bottom right to front right: (bottom+front+bottom-) front-(bottom-right-bottom+) right+
Right rotation method from bottom front to front: (bottom-right side-bottom+)+(bottom+front+bottom-) front-
3D: Hold the Rubik's Cube in a certain direction, so that the required Rubik's Cube is in the right front position. If the direction is wrong, do the following set of directional rotations.
.
Front-right directional rotation method (step *** 15): (right-down+right+) (down+front+down-) front-(down+right-down+)
Right+(down+front+down-) front-
Right and wrong methods:
This set of rotations is longer than the previous two steps. In the whole process of this series of rotations, there is only one vertex box (it was originally located in
The square at the top right has moved from its correct position to one position more than once. If you hand over one of them.
If you make a mistake or get confused, stop immediately and try to restore the top plane. Usually, you have to put the front.
The plane or right plane restores the box to the top surface, and then, in step 2, several sets of rotations are redone to restore the wrong vertex angle.
Stop. After that, try again from 3A.
Fourth step
Step 4: Corner of the bottom surface (lower left front, lower right front, rear left and rear right)
This step is to locate and orient the four corners on the first plane. This is done by positioning first and then orienting. This time,
The four squares are not placed separately, but are completed as a group at one time. Do it again according to the following instructions about 4A-4F.
You can complete a step.
4A: First, rotate the bottom surface so that as many corners as possible are in place, regardless of its direction for the time being (temporarily
Regardless of the edge squares on the bottom plane). At least two, sometimes even all, can be made by turning the bottom surface.
The four corners of the bottom plane are in the correct position. If there are still two squares in the wrong position, then their positions are just so.
On two adjacent or two opposite corners. For the former, 4b can be rotated; For the latter, a rotation of 4C can be made.
4B: If two wrong positions are adjacent, the next set of rotations can make them switch positions.
Rotation method for adjusting the left front of the bottom and the right front of the bottom (pay attention to correctly hold the Rubik's cube so that the two squares to be adjusted are in these two positions.
Set): (right-down-right+) (front+down+front-) (right-first+right+) down 2
4C: If two misaligned corners are opposite, the next set of rotations can adjust them.
Bottom front left, bottom back right (pay attention to hold the Rubik's cube correctly, so that the two squares to be adjusted are in these two positions.
Settings):
(Right-Down-Right+) (Front+Down 2 Front-) (Right-Down+Right+) Down+
4D: At this point, the four bottom corners have been properly placed. At this time, if the directions of these four bottom corners are incorrect, please press the following directions.
Normal rotation.
-There is only one rotation step in this step, but it should be used repeatedly. Just make sure to hold the lever correctly before each rotation.
Law.
-grip (this is the key):
Put the layer to be adjusted on the top (the whole process). Take the color of the center of the top surface as the standard color. Observe.
Are there standard color blocks at the four corners of the top surface?
-There is only one standard color: put this on the top, front and left.
There are two standard color patches at the same time:
-A: Two pieces are adjacent: put two pieces on the right front and right rear of the top respectively.
-B: Two pieces are opposite: put two pieces on the right front and left rear of the coat respectively.
Top edge (front bottom, left bottom, back bottom, right bottom)
Look at the position of the bottom edge:
(left-right+front+) (left+right-down 2) (left-right+front+) (left+right-)
Rotate forward. After the rotation, look at the bottom surface before deciding the next rotation mode.
Transfer mode: (left+right+front) (left+right-down-) (left+front-) (left+right-down-) (left-
Right+Up 2) (Left+Right-)
First of all, the concept of solution
According to the classification of Wikipedia, the solution and play of Rubik's cube are two concepts. Wikipedia divides the solution of Rubik's cube into edge first, angle first, layer first and Fridrich method; The Rubik's Cube is divided into ordinary play, racing play, minimum step reduction method, blind twist method, single twist method, foot twist method, pattern reduction method and so on. Therefore, in Wikipedia's view, the solution of the Rubik's cube refers to the steps of restoring the Rubik's cube; The play of Rubik's Cube refers to the way to restore Rubik's Cube.
Second, the classification of solutions
Generally speaking, the Rubik's cube is restored by restoring edges and corners alone or by combining edges and corners. Therefore, order reduction methods can be divided into four categories: hierarchical solutions, angular solutions, angular combination solutions and special solutions.
Hierarchical solution refers to the method of merging or reducing the corners of the first two layers separately, and then reducing the corners of the top layer. For example, Fridrich method, Petrus method, seven-step method of entry and other hierarchical methods. The corner method also belongs to this category. Angle solution refers to the method of recovering angle or edge independently without the influence of layer steps. For example, edge first method, angle first method, angle alternating method, etc. The combination solution of edges and corners refers to the method of restoring edges and corners after combining them in a certain way. Such as film first method, color first method, blind twisting method and so on. The essence of layered solution is also a special case of angular combination solution. Special solution refers to the reduction method with special requirements. Mainly includes: central block reduction, cloning Rubik's cube and pattern Rubik's cube, etc. Starting with the ways or methods of restoring the Rubik's cube, this book focuses on the layer priority method, edge priority method, angle priority method, slice priority method, color priority method, blind twisting method and synthesis method.
Layer by layer method is a solution to restore the Rubik's cube layer by layer. Fridrich method, Petrus method and two-layer one-step method all belong to the variation of layer-first method, so they are all included in layer-first method. The Rubik's cube solutions used by a group of top experts in the world are all Fridrich methods developed from the layer-first method or their improved methods. For example, Shotaro Makisumi of Japan restored the Rubik's Cube by Fridrich method, setting a world record of 12.26;
The edge priority method is to restore 12 edge blocks and then restore 8 corner blocks. This method has few formulas and is easy to remember. Suitable for lovers who don't want to remember the formula, but just want to restore the Rubik's cube and use it as a relaxation and entertainment. Corner priority method is a solution to restore corner blocks first and then edges. This method memorizes many formulas, so it will be faster than the general first-layer method. The master of angle priority method can restore the Rubik's cube within 30 seconds;
Slice priority method is a solution to restore the slices composed of specific corner blocks first, and then restore other blocks. After strict training, the players of the film first method can reach the master level of 3 steps per second and an average of 45 steps. According to the optimized formula and sequence, they can reach the level of reduction within 20 seconds.
Color priority method is a solution to restore the color direction of a certain surface first, and then restore other squares. It is also a very creative Rubik's Cube solution with good speed and efficiency.
Blind twisting is a solution to restore the Rubik's cube by memory without looking at it with eyes. Blind twisting is the dream of every Rubik's Cube player. This kind of play can best test people's memory and spatial imagination, and it is a performance show of Rubik's cube masters. Norwegian Gail Jugel Stade and German Ralph Laue took this performance to the extreme, twisting three Rubik's cubes blindly at a time!
Comprehensive method refers to a solution that combines two or more of the above methods, or it is difficult to classify them into the above methods.
Third, about other ways of playing.
About other ways of playing, this book only gives a brief introduction.
It is difficult to verify the specific time when the car resumed. However, it should be when fans have been able to skillfully restore the Rubik's Cube that they begin to pursue the fastest restoration.
Rubik's cube racing restoration has the following points: 1, and the method to be used is the simplest, but the following problem is that the fewer steps, the more formulas to be memorized; 2. The Rubik's Cube used should be the most suitable for racing cars, and it will not get stuck or slip, so there is a special Rubik's Cube lubricant, and the skills of building Rubik's Cube are endless; 3, the hand should be dexterous, because it is not the most important to have a good method and a good Rubik's cube. Both hands can skillfully rotate the Rubik's cube with the highest efficiency. At present, the fastest person to restore the third-order Rubik's Cube in the world is Japanese Shotaro Makisumi, who is nicknamed "Macky" by people in the Rubik's Cube circle. His average speed in the competition is generally around 13 seconds, and he has won the championship in recent years. The method used by him and most Rubik's Cube masters in the world is called Friedrich reduction method, which was invented by Ms. Jessica Friedrich.
The minimum step reduction method is a memorization reduction method and the most difficult way to play. In this game or competition, you can't turn the Rubik's cube, you can only observe the state of the Rubik's cube with your eyes, and then think about the least steps to solve the Rubik's cube. Although no one can prove what is the biggest upset state of the Rubik's cube (that is, the state that needs to be restored with the most steps), it is generally believed that the third-order Rubik's cube can reach the maximum state by randomly upsetting 50 steps. In this case, it takes as many as 23 steps to restore the original state through the program. At present, the world record of the least manual burden reduction is 28 steps, which takes 2.5 hours.