HOW TO SOLVE A 3*3 RUBIK’S CUBE ???
HOW TO SOLVE A 3*3 RUBIK’S CUBE ???
Not all, but most of the engineering students are familiar with Rubik’s cube. I also used to think how could it be solved? But after practicing it for 3-4 days watching a video in youtube, I learned it. Here, I would like to share it with those who are curious enough: how to solve this cube???
In 1974, a young Professor of architecture in Budapest (Hungary) named Erno Rubik created an object that was not supposed to be possible. His solid cube twisted and turned – and still it did not break or fall apart, that’s what we call Rubik’s Cube or Büvös Kocka (“Magic Cube”) or Hungarian Horror. It took well over a month for Erno to work out the solution to his puzzle. The most crazy thing about it is it has become the world’s best sold playing toy ever. Erno designed it to help students to understand spatial relationships in space about 3D geometry. Rubik’s Cube has six sides, with each side a different color (traditionally blue, green, orange, red, white, and yellow).
Some of the major events in its history are:
- 1974: Rubik created the first working prototype of the cube.
- 1977: The first ‘Magic Cube’ was sold in a Budapest toyshop.
- 1979: Tom Kremer negotiated and signed the distribution license across the world.
- 1980: The ‘Magic Cube’ was renamed The ‘Rubik’s Cube’.
- 1982: The first annual International Rubik’s Championships was held. More than 100 million Rubik’s Cubes had been sold and most had yet to be solved.
- 1995: Diamond Cutters Int. created the ‘Masterpiece Cube’.
- 2005: The Cube celebrated its 25th Anniversary in a special edition pack.
- 2007: Ernő Rubik awarded the prizes at World Championships in Budapest.
- 2013: A new cube was born! All new faster action mechanism and durable tough tiles.
Can you imagine, what’s the total number of possible configurations for Rubik’s cube?
:- It’s more than 43 quintillion possible configurations (43,252,003,274,489,856,000 to be exact).
Name the six sides of cube as Front(F), Back(B), Left(L), Right(R), Upper(U), Bottom(BT) and movements as C: clockwise, CC: counter clockwise, 2X: 1800. Then the procedures are as follows:
1.The White Cross:
Taking the yellow centered face, construct a white cross around the yellow center as shown in fig 1.
Remember, whatever movement you make, the block at center never alters its position from centre. Only the faces around it, get altered.
After this, considering this picture(Fig 1), in right side view, the central block of top row and the block just below it, make it same colour by rotating the middle layer of blocks horizontally. Then rotate the right layer of blocks by 1800 so that the two blocks just dealt move to central and lower row. Repeat the same steps for all four side blocks of white block. After you complete all of these, you will see a white cross just at the opposite side of your previously upper face. Then it would look like in fig 2.
2.The White Corners:
You may have maximum 4 corners unmatched with white colour. For this, if the white piece to be arranged is in the left side bottom row or right side bottom row, follow the step as follows:
Left side= R: CC, BT: C, R: C Right side= L: C, BT: C, L:CC
If the white piece is in left or right side upper row, bring it to bottom row first. If it is in exact bottom, make the bottom piece diagonal to the upper block to be filled and face the bottom white piece away from you and follow the rotation(for right side):
Right side: R: C, BT: C, R: CC
Now the white piece at bottom appears at the left or right side as previous pieces
and follow the previous steps to get a complete white side. It looks like Fig 3. You would notice a small T in every side of the same colour automatically as shown in the figure 3.
3.The sides of middle layer (white facing upward):
Face the white completed side backward to you. Rotate the front layer until the upper side bottom row middle block matches with the central block of upper side (note: block having yellow colour on either side are not preferred earlier). Then you need two cases here:
- For left block to replace right block (blue in front and red in upper block to replace the blue in upper and yellow in right side block as in fig 4), follow these rotations: F: CC, BT:CC, R: CC, M: CC, R:C (‘M: Middle horizontal layer’ ;Immediately rearrange the white side completely)
- For right to left replacement (opposite to previous) follow these steps:F: C, BT:C, R: C, M: C, R: CC (Immediately rearrange the white side completely) Repeat this until we get the top and middle layer match in all 6 sides. After this, the cube would look like this as in fig 5 and fig 6.
4.The Yellow Cross:
Arrange the position of cube(the face just opposite to white side) as shown in fig 7. If the position is similar to fig 8, first of all convert it to position in fig 7 following the same rotation stated as below.
After this, assuming the front side as shown in fig 7, perform the following rotations:
F:C, U: C, R: C, U: CC, R: CC, F: CC
5. The Yellow Corners:
You may get three different combinations as shown in the figure below(fig 9, fig10,fig 11). Performing the following rotations (make the front face as shown in the figures):
R:C, U:C, R:CC,U:C, R:C, U:2X, R: CC
Then the cube will be converted to form as shown in the figure 12. Perform the same rotation again making the front face as shown in fig 12, if required the same rotation is performed twice.Now you will get a complete yellow side as shown in fig 13.
6. The Corners:
If you get a complete upper side row(current position: complete yellow at upper position) of same colour in any side as shown in fig 15 or at least two colour same in one upper row as shown in fig 14, rotate the upper layer horizontally to the matching colour side and face the side just back to you:
Perform the following rotation as:
R:CC, F:C, R:CC, B:2X, R:C, F:CC, R:CC, B:2X, R: 2X
If you have cube like fig 15, it gets converted to matching corner at once but if you have cube like fig 14, first you get a single matching corner, rotate the upper row to its matching side, face it back, and perform the above rotation once again. Then you will get a complete corner matching cube as shown in fig 16.
7. Clockwise or Anticlockwise Rotation
The only task remaining now is to rotate the middle pieces of upper row (current position: white facing downward) either clockwise or anticlockwise to have perfect matching as shown in fig 17 and 18.Perform the following rotations as follows:
R:2X, U:C, R:C, U:C, R:CC, U:CC, R:CC, U:CC, R:CC, U:C, R:CC
R:C, U:CC, R:C, U:C, R:C , U:C, R:C, U:CC, R:CC, U:CC, R:2X
Finally, you will get a perfectly matched Rubik’s cube as shown in fig 19,20,21.
It requires a lot of practice to be a master of it. You can also develop your own algorithm to solve a 3*3 Rubik’s cube in course of practicing.
Some world records on Rubik’s Cube:
- Quickest solution time: 5.55s, Mats Valk (Netherlands), 2013 Zonhoven Open
- Average solution time: 7.53s, Feliks Zemdegs (Australia), 2012 Australian Nationals
- Blindfolded solution time: 23.80s, Marcin Zalewski (Poland), 2012 European Rubik’s Cube Championship
- Blindfolded most cubes: 24, Tim Habermaas (Germany) , 2008 German Open
- One handed solution time: 9.53s, Giovanni Contardi (Italy), 2012 Italian Championships
- Using feet only: 27.93s, Fakhri Raihaan (Indonesia), 2012 Celebes Cube Competition
- Most cubes in 24 hours: 4786, Milán Baticz (Hungary), 2008
- Robot solution time: 5.27s, Cube Stormer II, By Mike Mike Dobson and David Gilday
- Youngest person to solve: 3 years, 6 months, 5 days , Yi Hui (China), in 2:43:34 minutes at the 2011 ShenYang Open
Thank you all, for your time to read this.