## Wednesday, November 28, 2007

### Rubik's Cube

A Rubik's Cube!! I always had a fancy for one of these but I dont know why I never had one before. Maybe I havent bought a toy for long I guess. So off we're going to bhutan and I buy this russian cube (ok I didnt know it was called rubik's cube), and then I realise this thing seems impossible to solve. Didnt spend much time on it either. It's a mathematical toy, and I kinda have this image of it being at every programmer's desk, twisting it around as he unravels the coding!! Must have seen that in some movie, I'm sure.

So there was this Hungarian Inventor- Erno Rubik. And he made this toy around in the 1970's. The Rubik's cube has more than a trillion possible permutations and combinations, but only ONE correct solution, thats what makes it special I guess. I am surely not smart enough to figure out a solution on my own. But then what is the internet for!!

The Internet if used properly has the solution to everything these days. So first I read bit, but couldnt really understand what they were trying to say. But then this youtube video makes things clear. It took me nearly 2 hours to solve it the first time. And I was somehow messing things up all the time. But last night I reduced it to 10 mins!!! Thats amazing. This one is cheap, so takes effort to move around, and I am sure If I had a good quality one, I could reduce the time further.

So what does solving this bring me? I don't know, maybe I thought that after solving it, it would open up and out will come some kind of treasure!! Yeah, thats what should have happened really. For the believers anyhow. But still it gives me bragging rights!! And yeah I hope to remember the Algorithm for fun. But the why have I been solving one of these even in my dreams?? Thats creepy, so I should stop with this thing now.

So, I kinda summarised the whole algorithm like this for me

U = Up, R = Right, L = Left, D = Down, F = Forward, I = Inverted

Step 1 : First get the top layer, choose any center colour and make a top cross, using FI, U, LI, UI. Then get the top corners using RI, DI, R, D.

Step 2 : Next go for the middle layer by inverting the cube, this algorithm is difficult if u look at it, but I got the logic embedded in my mind for this, so I dont have to write it. You start by moving the top, and then either the left or the right, and then reverse the top, and then reverse the left/right, and then top again, and forward, and then u can actually see what to do, so I never memorized that.

Step 3 : Next its the bottom layer. Now this is the tough part, and I am still screwing it up more often then not. There a lot of steps, some may not always be needed, depending on how the cube turns out for u.

First, we need a cross for the bottom layer (inverted cube), by using F,R,U,RI,UI,FI.
Thats easy to remember FRURUF, with the latter half inverted.
Next, we need the cross to be proper with the sides, using R,U,RI,U,R,U,U,RI. Again easy to remember its just RURURUUR, with U's never inverted and R's inverted alternatively.
Next, we need the corner's to be proper with the sides, using U,R,UI,LI,U,RI,UI,L. This one is tricky, but remember as URUL URUL. With U's alternatively inverting, and R's and L's are going up and then back down.
Then finally, its the last thing to do, the corners need to be rightly faced. SO use it earlier easy Algo - RI,DI,R,D.

Sounds complicated but gets the job done usually. But somehow I am still messing up. I dont know why. Maybe I skip one move somewhere. So here is to Erno Rubik for making such a wonderful toy!!!

#### 1 comment:

Anonymous said...

that's basically the out of the box algorithm when you buy an original cube. well done for copying it.