From kubo@jacobi.math.brown.edu Thu Apr 23 10:56:44 CDT 1998 Article: 190788 of sci.math Path: gannett.math.niu.edu!corn.cso.niu.edu!vixen.cso.uiuc.edu!cdc2.cdc.net!nntp.giganews.com!news.maxwell.syr.edu!news-peer.sprintlink.net!news.sprintlink.net!cpk-news-hub1.bbnplanet.com!cam-news-feed1.bbnplanet.com!news.bbnplanet.com!cocoa.brown.edu!kubo From: kubo@jacobi.math.brown.edu (Tal Kubo) Newsgroups: sci.math Subject: Re: Minesweeper Date: 23 Apr 1998 02:51:27 GMT Organization: Math Department, Brown University Lines: 12 Message-ID: <6hmabf$s9a@cocoa.brown.edu> References: <353e01af.724384@news.mindspring.com> NNTP-Posting-Host: jacobi.math.brown.edu Xref: gannett.math.niu.edu sci.math:190788 Minesweeper is NP-complete, in the sense that determining whether a given screen display is consistent with a placement of mines is NP-complete. (See http://for.mat.bham.ac.uk/R.W.Kaye/publ/minesw.ps for the proof, based on programming Boolean circuits as Minesweeper configurations). Related folklore: evaluating positions in Robots is NP-complete. IIRC the idea was to reduce SAT instances to starting positions where the robots are inside a strip of width 2 or 3, and the player is on one side of the same strip.