How to build a Rubik's Cube 5x5x5 (part 2)

So, we are gradually entering the final straight of the 5x5x5 Rubik Cube assembly! It remains to remove the edges of the cube and the central squares. In addition, there is a cube emulator program, so even if there is no cube, you can try to assemble it on a PC.
Link to the first part




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Iv. The remaining side intermediate cubes

Side intermediate cubes remained with us only in U2, D2 and D. Here we will be helped by two combinations: K9 and K10 and they are symmetrical. Note that cubes of the same color have a different internal structure (I already wrote about this, one of them is “left”, the other is “right”), so if you want to move such a cube from D to D2 or U2, look at which of these faces it will be oriented correctly. Notice that K9 and K10 move the cubes in such a way that the color designated as B goes to C, and then to the left A (see the figure on the right). Before using the combination, turn D at your convenience - then it will be possible to return it without any problems. An approximate instruction on assembly - assemble parallel cubes in D and in D2 with U2 so that the ones that are incorrectly placed are approximately equally divided everywhere. The only bad situation that can occur is that in one of the layers of U2 or D2, two adjacent dice stand correctly, and the other two need to be swapped. To do this, perform the following operations (we assume that the problem arose in D2, for U2 it is done similarly): Place the cube so that both dice that need to be swapped are on the left side (L) and apply K10 . Next, turn the four upper layers clockwise (as viewed from above) and again apply K10 . Then just turn the D2 so that the colors on the edges of the cube match. That's all! The result is in the picture on the right.
Since I myself understood this algorithm a lot of time, I made a video of this combination

By the way, the assembly algorithm on one well-known site suggests an algorithm similar to K9 and K10 for assembling lateral middle cubes. You can try, but it is believed that it does not work. The fact is that the above mentioned situation may arise (in connection with which I shot the video) and its elimination algorithm will not work for the middle horizontal layer, since it contains the center cubes (the point is at the very last turn, which returns the lateral middle cubes into place, but moves the centers to other faces).

V. The remaining five central squares

This is where the K11 , K12 and K13 combinations will help. Before using them, you often have to turn L and F, and at the end return it to its place in the reverse order.
Combinations can be perceived as moving cube A to the left face, and cube C to the front. The fact that the order of the cubes changes in the left face is completely irrelevant, since Before the following combinations, you can rotate L and F as you like (these combinations, unlike the previous ones, do not touch the rest of the dice at all, so you can use it from any position). Also here, we first use U3 and U3 turns. This is the turn of the third layer, when viewed from above (the turn of U3 is the same as D3 ', and vice versa, U3' is similar to the turn of D3). In addition, it is not necessary to use all three combinations. It suffices only K12 and one of the remaining, because K11 and K13 move the same class of cubes. For example, it was more convenient for me to use K13 when I was just learning how to assemble a cube. Now I use everything (it speeds up the assembly a bit and prevents some errors that occur mainly due to the need to rotate both the left and front faces in front of the combination).

Conclusion

So we collected a cube. Using this scheme, you can assemble a cube not only of size 5x5x5. To build a 2x2x2 cube, you only need to collect the corners. To assemble a classic 3x3x3 cube, assemble the top edge using only the assembly algorithms for the side medium and corner cubes, and then everything is exactly up to the end of section III . The 4x4x4 cube is also easy to assemble - the principal differences between even and odd dimension cubes are only in the fact that the “even” cubes do not have central and lateral middle cubes, so you can skip some of the steps to build the cube (although I don’t have a 4x4x4 cube, I can easily collected it in a self-writing emulator program). The rest is going similar.
As for large cubes, I have some thoughts on this. One facet most likely can be collected without problems on any cube. Also, the above-described algorithms are applied without problems to assemble the “edge parts” of the cube (p. I – IV ). It remains to deal only with large central squares. Most likely, there is something similar to section V. After a month and a half, they will send me a 7x7x7 cube, and if I figure it out, I'll add instructions here.

Program

I have already mentioned that I wrote a program with which you can try your hand at assembling (in the absence of a real cube). It does not differ from many similar programs, perhaps, except for experimental control and potential support for various structures like the Rubik's Pyramid. This program was written long ago, at the end of the 11th grade to the city conference on informatics. After that, the demo was posted here , but did not receive much support, so the project was abandoned. If this is really something worthwhile, you can tell me, most likely there will be time to do it.
Download

Description

The program uses GAPI OpenGL and pure WinAPI, so there is a high probability that it will work under Wine too. Run CubeLauncher, enter a number from 1 to 10, press enter, the desired cube is loaded. Control the mouse, if you move with the left button pressed, the cube itself rotates. If you hover the mouse on one of the semitransparent rings and twist the scroller, then the corresponding face rotates (the scroller forward is the rotation in the direction of rotation of the ring). Immediately I apologize for looking in different directions cursor (apparently, I beat Worms 3D).
For example, I made a video of the 2x2x2 cube assembly:

Among other things, there is a pyramid (it is going to be elementary, made just to demonstrate the possibilities)

Acknowledgments

Logonoff - for the invaluable assistance in the design of pictures. Without it, I quickly would not learn to draw in Photoshop and make at least some pictures.
Oxystin - for help in checking the algorithm. Without it, I would not be sure that I did not make any inaccuracies or errors in the algorithm.