From anandrao@hk.super.net Fri Feb 25 03:32:04 1994 Return-Path: Received: from hk.super.net by life.ai.mit.edu (4.1/AI-4.10) for /com/archive/cube-lovers id AA05974; Fri, 25 Feb 94 03:32:04 EST Received: by hk.super.net id AA21734 (5.65c/IDA-1.4.4 for cube-lovers@life.ai.mit.edu); Fri, 25 Feb 1994 16:31:42 +0800 Date: Fri, 25 Feb 1994 16:18:56 +0800 (HKT) From: "Mr. Anand Rao" Subject: Re: your mail To: Jan de Ruiter Cc: cube-lovers@life.ai.mit.edu In-Reply-To: <2038.9402181343@xirion.xirion.nl> Message-Id: Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII On Fri, 18 Feb 1994, Jan de Ruiter wrote: > > Sorry about not reporting this earlier, but my search for solutions for > Rubiks Tangle 10x10 confirms the finding of Don Woods: no solutions! > [snip] > we could re-define the puzzle as follows: > find which four pieces to duplicate in order to find solutions for > the 10x10. > If the number of solutions varies depending on the choice, you could > even add a restriction: > find which four pieces to duplicate in order to find a set which has > the minimum number of solutions for the 10x10. ^^^^^^^ The kind Mr. Rubik has already done that - the minimum is - ZERO! The revised problem can be solved fairly easily using your program ( I don't know, though, how long it takes to run to completion for the 10*10 case) - try to place only 99 tiles out of the 100 given tiles. You may have several sub-solutions. It is then easy to determine for each of these sub-solutions which tile you need to complete the 10*10 mosaic. If this pattern has already been duplicated, i.e. you need THREE numbers of this tile to find the complete solution, this sub-solution will not work and so examine the next sub-solution .... Hopefully you find the solution this way. After running the program for the 99 tiles, the additional time required to solve the problem defined by you should not be significant because that would be a linear process. Anand.