Path: csiph.com!usenet.pasdenom.info!bete-des-vosges.org!news.redatomik.org!newsfeed.xs4all.nl!newsfeed1.news.xs4all.nl!xs4all!post.news.xs4all.nl!not-for-mail Return-Path: X-Original-To: python-list@python.org Delivered-To: python-list@mail.python.org X-Spam-Status: OK 0.187 X-Spam-Level: * X-Spam-Evidence: '*H*': 0.63; '*S*': 0.00; 'yet.': 0.04; 'run,': 0.09; 'cc:addr:python-list': 0.11; "board's": 0.16; 'devise': 0.16; 'from:addr:rosuav': 0.16; 'from:name:chris angelico': 0.16; 'mean,': 0.16; 'slow,': 0.16; 'those,': 0.16; 'wider': 0.16; 'alpha': 0.16; 'sat,': 0.16; 'do,': 0.16; 'wrote:': 0.18; 'rules': 0.22; 'cc:addr:python.org': 0.22; 'error': 0.23; 'mathematical': 0.24; 'simpler': 0.24; 'fine': 0.24; 'cc:2**0': 0.24; 'values': 0.27; 'header:In-Reply-To:1': 0.27; 'point': 0.28; 'testing': 0.29; '(this': 0.29; 'am,': 0.29; 'have,': 0.30; 'message- id:@mail.gmail.com': 0.30; "i'm": 0.30; 'work.': 0.31; 'bunch': 0.31; 'consequence': 0.31; 'purely': 0.31; 'them?': 0.31; 'run': 0.32; 'linux': 0.33; 'guess': 0.33; 'sense': 0.34; 'could': 0.34; "can't": 0.35; 'anywhere': 0.35; 'but': 0.35; 'received:google.com': 0.35; 'version': 0.36; 'really': 0.36; 'crazy': 0.36; 'possible': 0.36; 'list': 0.37; 'fact': 0.38; 'does': 0.39; 'structure': 0.39; 'even': 0.60; 'dave': 0.60; 'eventually': 0.60; 'new': 0.61; 'entire': 0.61; 'matter': 0.61; 'simply': 0.61; 'become': 0.64; 'more': 0.64; 'different': 0.65; 'direct': 0.67; 'mar': 0.68; 'book.': 0.68; 'fun?': 0.68; 'score': 0.74; '100': 0.79; 'trial': 0.83; '"not': 0.84; '2015': 0.84; 'challenge.': 0.84; 'firing': 0.84; 'game,': 0.84; 'points,': 0.84; 'resorts': 0.84; 'testers': 0.84; 'yet?': 0.84; 'angel': 0.91; 'to:none': 0.92 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:cc :content-type; bh=WXe+gTPH3KPRGq7v9ChX/cVgJsQwRglv0QjaLUzl3P4=; b=dn8LXB28LvIYcMSGN70Zo8U2bvG4kq7WakzsZKpb3ogSGtqsyJDsnQTateEPfbdmpJ ddxRLOYCi7wDZbYAPp3yES7qXa4DdHxm8QVPKu4zP/+ela4mNIPbJcc8PdQaskt7jnIF a76cqPhWDIpyeOLfqZcb4T8URT6o9ePudfjaT457ytE5QInxGsGDHcw8Acg1FPGc+rJv 65g7nbhmws/Ur3JqJ+uegHu+M+h/gTRbV/rxREa1oBgolv/rYKFXM5HjPlS/UhZzFrKD paDSjGP+ye6SdvH3a4x7j0NhZrp4WRA0Cax8W7vXRAGMqHpOKs0QMmQ3IeDMJU14sw2q op2g== MIME-Version: 1.0 X-Received: by 10.107.134.219 with SMTP id q88mr28479774ioi.27.1427462705667; Fri, 27 Mar 2015 06:25:05 -0700 (PDT) In-Reply-To: <551557B3.5090102@davea.name> References: <87r3sdnw5t.fsf@elektro.pacujo.net> <87fv8sndw1.fsf@elektro.pacujo.net> <551557B3.5090102@davea.name> Date: Sat, 28 Mar 2015 00:25:05 +1100 Subject: Re: Sudoku solver From: Chris Angelico Cc: "python-list@python.org" Content-Type: text/plain; charset=UTF-8 X-BeenThere: python-list@python.org X-Mailman-Version: 2.1.19 Precedence: list List-Id: General discussion list for the Python programming language List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Newsgroups: comp.lang.python Message-ID: Lines: 36 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1427462713 news.xs4all.nl 2915 [2001:888:2000:d::a6]:46778 X-Complaints-To: abuse@xs4all.nl Xref: csiph.com comp.lang.python:88152 On Sat, Mar 28, 2015 at 12:14 AM, Dave Angel wrote: > But now I have to disagree about "true Sudoku puzzle." As we said earlier, > it might make sense to say that puzzles that cannot be solved that way are > not reasonable ones to put in a human Sudoku book. But why isn't it a "true > Sudoku puzzle"? > > Isn't the fact that one resorts to trial and error simply a consequence of > the fact that he/she has run out of ideas for more direct rules and the data > structures to support them? > > The simpler rules can be built around a list of possible values for each > cell. More complex rules can have a more complex data structure for each > cell/row/column/box. And when you run out of ideas for all those, you use > guess and backtrack, where the entire board's state is your data structure. At that point, it may make a fine mathematical curiosity, but it's not really a fun puzzle any more. Does "true" mean "playable"? I mean, I could devise a game in which you point your gun anywhere and shoot, and you kill someone and score 100 points, and no matter what you do, you can't die, and the game never ends. No strategy, no challenge. No goal. Is that a game? Well, it's virtually the same thing as any other FPS, just with a few simplifications. Is it fun? Not very. So is it a "true game"? (This is not purely theoretical, incidentally. I'm currently alpha testing a new game that I backed on Kickstarter. The Linux version is built against a different libc than I have, so to make it even run, I have to jump through some crazy hoops; it's slow, clunky, and not exactly a fun game... yet. The alpha isn't designed to be entertaining, it's designed to be a proof-of-concept and to let a bunch of testers find issues before they go to a wider audience. Eventually it'll become a fun game, but at the moment, firing it up is work. Does that mean it's "not a true game" yet? Philosophical debate!) ChrisA