From modestr@federal.unisys.com Mon Apr 8 12:03:25 1996 Received: from www.han.federal.unisys.com by life.ai.mit.edu (4.1/AI-4.10) for /com/archive/cube-lovers id AA08118; Mon, 8 Apr 96 12:03:25 EDT Received: from homer.MCLN.Federal.Unisys.COM by www.han.federal.unisys.com (8.6.12/mls/8.0) id MAA17345; Mon, 8 Apr 1996 12:03:19 -0400 Return-Path: Received: from h3-90.MCLN.Federal.Unisys.COM by homer.MCLN.Federal.Unisys.COM (8.6.12/mls/4.1) id MAA27608; Mon, 8 Apr 1996 12:06:35 -0400 Message-Id: <199604081606.MAA27608@homer.MCLN.Federal.Unisys.COM> Date: Mon, 08 Apr 96 12:03:28 -0700 From: Ron Modest X-Mailer: Mozilla 1.22 (Windows; I; 16bit) Mime-Version: 1.0 To: Cube-Lovers@ai.mit.edu Subject: square 1 help Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=iso-8859-1 Regarding swapping two edges on Square-1. You prompt me to write about something I have been meaning to get around to for a long time. Long ago I found a way to swap two edges using a complicated sequence. After considerable unsuccessful effort to improve the solution, I bought Richard Snyders amazing book "Turn to 1" from Puzzletts. ( HTTP://WWW.PUZZLETTS.COM/ ) His solution is essentially the same as mine. His method of documentation obscures what is really going on and consequently it would be very hard to memorize. The principal is straight forward and follows these steps. Move all the edge pieces to the same side in an orderly sequence. Turn the side that has all corner pieces, one position. Retrace all the moves that brought the edge pieces to the same side. Fix any thing that got messed up in the process. (this is what I call collateral damage) Snyder's solution optimizes the process to minimize the collateral damage but any variation on the steps listed above will work. On a related subject.... How to get the puzzle into the shape of a cube after initial scrambling. Snyders book shows pictures of all possible scrambled shapes. Each has instructions for making a few turns and the next diagram to refer to. This process may be optimal for getting it into a cube shape but it is nearly impossible to memorize. I am sure everyone who works with the puzzle learns some shapes that are close to the cube shape but it may seem nearly impossible to generally solve in any orderly way. Well consider the following strategy: Collect all the edge pieces on the same side. They can all be side by side in what Snyder calls the Hoofprint pattern or in the Moon pattern that has two groups of four edges on the same side. Then move half of the edges to the opposite side. Then move half of the edges from the top to the bottom and half of the edges from the bottom to the top, but do so in a way that separates them into groups of two. You are then with a couple of twist of making a cube. The beauty of the strategy is that to obtain perfect final symmetry, you first take it to a position of maximum asymmetry. Every turn after that keeps it symmetric. This method will not generally be the optimum solution but it is straight forward and easily learned. I said this is related to the previous subject of swapping two edges because both require reaching a position will all the edge pieces on one side. I might not have ever found the method for swapping two edges if I had not first adopted this method for getting it into a cube shape first. While I am sending out a message let me recommend that everyone include their mail address when the send a message. Recently a couple of messages did not. I would have send the author a personal message answering a simple question but didnt want to bother everyone else. One such question was about obtaining 3x3x3 cubes. They are available in many chain toy stores including "The Game Keeper" and "LearningSmith". Most puzzles are available from Puzzletts also. I also notice that several local stores are carrying Rubiks Magic again. The colors are different than the originals. Cube Trivia.... In 1982 a Worlds Fair was held in Knoxville Tenn. USA.. At the enterance to the Hungarian pavalion was a Rubik's Cube about 4 feet on a side mounted on a pedistal. At that time a Rubik's Cube was a universially recognized symbol. Walter Smith near Washington D.C. WALTS@FEDERAL.UNISYS.COM