From Don.Woods@eng.sun.com Wed Dec 15 20:39:18 1993 Return-Path: Received: from Sun.COM by life.ai.mit.edu (4.1/AI-4.10) for /com/archive/cube-lovers id AA19011; Wed, 15 Dec 93 20:39:18 EST Received: from Eng.Sun.COM (zigzag.Eng.Sun.COM) by Sun.COM (4.1/SMI-4.1) id AA12769; Wed, 15 Dec 93 17:39:17 PST Received: from colossal.Eng.Sun.COM by Eng.Sun.COM (4.1/SMI-4.1) id AA06793; Wed, 15 Dec 93 17:38:04 PST Received: by colossal.Eng.Sun.COM (5.0/SMI-SVR4) id AA26306; Wed, 15 Dec 93 17:39:20 PST Date: Wed, 15 Dec 93 17:39:20 PST From: Don.Woods@eng.sun.com (Don Woods) Message-Id: <9312160139.AA26306@colossal.Eng.Sun.COM> To: cube-lovers@ai.mit.edu Subject: Re: Description of Tangle, Part 2 X-Sun-Charset: US-ASCII Content-Length: 897 > Is this the reason why Rubik has gone into hiding? I haven't seen any > puzzle from him after this set of 4 released in 1990/1991. Hm, didn't "Square-1" come out later than the Tangles? Regarding solving the Tangle, I forgot one other minor optimisation: When my program is picking a corner piece other than the first, it requires that the piece "number" be less than or equal to that of the first corner. I.e., it refuses to search for solutions that are rotations of other solutions. I've modified my program to try the 10x10, but indeed, it's taking a long time. (Current estimate is it will take over a year to finish.) I suspect that fact that pieces aren't "used up" as fast -- i.e., since there's at least four of any given piece, there will usually be at least one of whatever you're looking for for quite a ways down the search tree -- makes this approach intractible. -- Don.