This can be done quite easily – first get the “edge cubelets” (those which have two free faces) into place, then the “vertex cubelets”. to get all the cubelets with some given color into the correct position and orientation. The first step of the solution is to “build a layer” – i.e. There is nothing special about the sequence RuRLdBBFRulBDD the idea is just to observe how scrambled the cube can become with the application of a very small number of moves. Thus a sequence of moves – and its effect on a cube (in solved initial state) is illustrated in the following figure: The one useful item I remember from that book was the notation for the cube operations if we orient the cube in a particular way, and label the faces as up, down, front, back, left, right (in the obvious way), then an anticlockwise twist of one of these faces is denoted by a lower case letter u,d,f,b,l,r and a clockwise twist by the corresponding upper case letter U,D,F,B,L,R. So the appearance of my kids playing with a cube 33 years later is the perfect opportunity for me to go back and work out a solution from first principles. At the time it seemed a baffling mystery, and I wouldn’t have known where to get started to come up with such moves on my own. In retrospect I find it a bit surprising – in view of how much effort I put into memorizing sequences, reproducing patterns (from the book), and trying to improve my speed – that I never had the curiosity to wonder how someone had come up with this list of “magic” operations in the first place. The solution in the book was a procedure for completing the cube layer by layer, by judiciously applying in order some sequence of operations, each of which had a precise effect on only a small number of cubelets, leaving the others untouched. I remember taking part in an “under 10” cube-solving competition in the heat of the moment, I panicked and got stuck with only two layers done (since there were only two competitors, I came second anyway, and won a prize: a vinyl single of the Barron Knights performing “Mr. Within a year, Rubik’s cube fever had taken over – my Mum bought me a little book explaining how to solve the cube, and I memorized a small list of moves. In the morning the cube had been solved – I remember being pretty impressed with Dad for this (later he admitted that he had just taken the pieces out of their sockets). After a couple of hours of frustration trying to restore the initial state, I gave up and went to bed. He said I could have a play with it if I was careful not to scramble it (of course, I scrambled it). I remember seeing my first cube some time in early 1980 my Dad brought one home from work. They had persisted with it, and even managed to get the first layer done. Every so often they root through some box and uncover some archaeological treasure so it was that I found Lisa and Anna the other day, mucking around with a Rubik’s cube. All our junk was shipped to us, and the boxes we didn’t feel like unpacking are all sitting around in the attic, where the kids have been spending a lot of time this summer. After a couple years of living out of suitcases, we recently sold our house in Pasadena, and bought a new one in Hyde Park.
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