Rubik's Cube

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Georacer

Joined Nov 25, 2009
5,182
I 'd never touched the toy. It seemed like a mundane, boring, show-off action.

Recently an aunt of mine got herself to solve it, so she bought one. She failed in trial and error, so I decided to give it a try. Child of the 00s as I am, I googled for the algorithm and sure enough it popped up.

It took me about half an hour to understand it and a day to memorize it.

Now knowing how to solve the puzzle, I must admit that it gives a sense of content each time you solve it. It's like reciting a short poem or a song or a gymnastic exercise.

Isn't life weird?
 

DerStrom8

Joined Feb 20, 2011
2,390
I bought one about 8 years ago. It took a friend of mine to help me figure out how the parts moved, and how I could move so-and-so a side to keep so-and-so blocks in the same place. Since then I have been able to solve it every time.

I don't know why it's so fun. I suppose it's everyone's look of amazement when you do manage to solve it. Makes you look really smart, I guess :p:D

Matt
 

ErnieM

Joined Apr 24, 2011
8,377
Back in the day... it was summertime (sweet summertime) and I came across Douglas Hofstadter's Metamagical Themas column in Scientific American on The Cube. Looked like an awesome puzzle so I got one. With no classes to attend and the "mechanical solution" well in hand (you can disassemble and reassemble a cube without any tools) I took the notation for moves Hofstadter described and looked for interesting things. Within a week I could solve the cube about half the time, the other half I had to mix it up. A day later I found a simple "mix up" that always worked so made it my third move, and with just three moves one can solve any cube.

My times are around 1:30. Twice I broke 1 minute on the iPad app.

A "move" is a canned sequence that moves just certain pieces, and they fit onto your solution method. My method is to solve one layer (face and the sides together), then the opposite 4 corners (they all come up together), middle edges, the top edges. Thus my corner move will mess up edges, but I don't care as I have not solved them yet. My edge move just moves 3 edge cubies, and I use it forwards and backwards: I count it in my head but it's mostly finger memory.

Notation: Hold the cube between your thumb and index finger: your thumb is on the Front (F) face, finger on the Back (B) face, other faces are Top, Left, and Right... I never move it so I don't remember the name for the bottom. I don't move the back or left either. So R by itself is a 1/4 clockwise turn of the R face, R' is same but counter clockwise. R2 is a half turn (either direction, it's symmetrical!).

Here's my moves:

EDGE 3-cycle:
R U R U R' U' R' U' R' U

CORNER 3 CYCLE:
F n*(R U R' U') F'

where the part in parenthesis is done 1,2 or 3 times. I've since discovered this shortcut for the n=3 case:
R2 U2 R U2 R2

CORNER SWAP:
R U R U R U R U R U R U R U R U' R2 U2 R

I've since found the following transform replacement:
R U R' U' F' U' F

Now also R2 U2 R2 U2 R2 U2 is also interesting (useful) as it can be used (with transformation and conjugation) to flip all 4 top edges.

Transformation and conjugation you ask? A transform is a "move." A conjugation is a small set up move done before a transform, and again in reverse after. It extends what a transform can do.

I currently own 3 or so cubes. I just had to toss out my favorite as it was just worn out, but it turned so nice! Most cubes (especially when new) are very difficult to turn.

An interesting cube I got as a present has no colors, it is entirely metallic in color, but the cubies are different sizes. I can solve it by my normal means, but it takes lots of concentration (solving the standard cube is mostly finger memory and the occasional observation).

I also have a ball cut into 8's, marked with rings. Another present I unfortunately uttered "oh, it's just the corners of a cube!" in excitement when I saw how to solve it... which I did in a few minutes. Those together made the gift givers upset thinking they gave me a simple puzzle... but I really like it and it's more of a challenge to me then a straight out cube as it needs more thought each and every time.
 

maxpower097

Joined Feb 20, 2009
816
I'm too dumb for it. I tried when I was a lil kid, probably too young, then never tried again as a teen or adult. I still play with my slinky though.
 

tshuck

Joined Oct 18, 2012
3,534
I still play with my slinky though.
This is a family site!:eek:


Never had a desire to solve a Rubick's cube once I realized there is an algorithm for it. Don't know why, just felt a little less impressive to me when there was a set of rules that could solve it regardless of whether or not I picked it up...
 

jaygatsby

Joined Nov 23, 2011
182
I think that the thing was invented with the intention of people solving it without looking at teh intertubes... cheating != accomplishment.
 

DerStrom8

Joined Feb 20, 2011
2,390
I think that the thing was invented with the intention of people solving it without looking at teh intertubes... cheating != accomplishment.
I agree with that. Cheating takes all the satisfaction out of it for me. While I learned what moves do what from a friend years back, I didn't google the algorithm. However, since I did learn from a friend, I don't get as much satisfaction as I would if I solved it without the "lessons".

I truly admire the people who can do it just by looking at it. That takes skill.
 
I'm with Spinnaker on this one. I got one for christmas when I was about 8. I disappeared off with it and showed it to my mum solved within 15 minutes. Cue much amazement. After a while I came clean that I'd figured out pretty quickly that you can peel the stickers off without them ripping and stick them back on.

I've used that in a few job interviews to illustrate my 'practical approach to problem solving' and it's always gone down well :)
 
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