Search Results

Search found 517 results on 21 pages for 'puzzle'.

Page 9/21 | < Previous Page | 5 6 7 8 9 10 11 12 13 14 15 16  | Next Page >

• How to Check Authenticity of an AJAX Request

  - by Alex Reisner

  I am designing a web site in which users solve puzzles as quickly as they can. JavaScript is used to time each puzzle, and the number of milliseconds is sent to the server via AJAX when the puzzle is completed. How can I ensure that the time received by the server was not forged by the user? I don't think a session-based authenticity token (the kind used for forms in Rails) is sufficient because I need to authenticate the source of a value, not just the legitimacy of the request. Is there a way to cryptographically sign the request? I can't think of anything that couldn't be duplicated by a hacker. Is any JavaScript, by its exposed, client-side nature, subject to tampering? Am I going to have to use something that gets compiled, like Flash? (Yikes.) Or is there some way to hide a secret key? Or something else I haven't thought of? Update: To clarify, I don't want to penalize people with slow network connections (and network speed should be considered inconsistent), so the timing needs to be 100% client-side (the timer starts only when we know the user can see the puzzle). Also, there is money involved so no amount of "trusting the user" is acceptable.

  Read the article

• How to get full query string parameters not UrlDecoded

  - by developerit

  Introduction While developing Developer IT’s website, we came across a problem when the user search keywords containing special character like the plus ‘+’ char. We found it while looking for C++ in our search engine. The request parameter output in ASP.NET was “c “. I found it strange that it removed the ‘++’ and replaced it with a space… Analysis After a bit of Googling and Reflection, it turns out that ASP.NET calls UrlDecode on each parameters retreived by the Request(“item”) method. The Request.Params property is affected by this two since it mashes all QueryString, Forms and other collections into a single one. Workaround Finally, I solve the puzzle usign the Request.RawUrl property and parsing it with the same RegEx I use in my url re-writter. The RawUrl not affected by anything. As its name say it, it’s raw. Published on http://www.developerit.com/

  Read the article

• Professional Windows Phone 7 Game Development: Creating Games using XNA Game Studio 4

  - by Chris Williams

  In 24 short days*, my (along with the awesome George W. Clingerman) first book will be released:   Professional Windows Phone 7 Game Development: Creating Games using XNA Game Studio 4 (or as we like to call it, that damned 550 page monstrosity that nearly killed us) Weighing in at 552 pages and featuring a foreward by the legendary James Silva (Ska Studios, creator of The Dishwasher: Dead Samurai, The Dishwasher: Vampire Smile, I MAED A GAME W1TH Z0MB1ES 1NIT!!!1, and more...) this book gives thorough coverage of XNA 4.0 as it relates to Windows Phone 7. The book is written in a light, conversational tone, which means (unlike some books) you won't be compelled to gouge your eyes out with a rusty spork after reading the first few pages. At least, that’s the intent. If you do feel compelled to engage in some feats of eye-gouging sporkage, we (the authors of this book) would like to point out that we are not responsible and that seeking the help of a mental health professional might be advised. (We’re not qualified to dispense medical advice either.) The book is structured to introduce relevant material first, with code snippets and samples of how to use various phone features and XNA concepts, with helpful side notes along the way. After you've been exposed to a few chapters worth of concepts, you get the chance to bring them together by building a game that leverages those features. This book contains THREE (3!) complete games, including: Drive & Dodge (a racing game), Poker Dice (roll dice to make poker hand combinations) and Picture Puzzle (take a photo and turn it into a jigsaw puzzle.) Writing this book has been an incredible experience, and we hope reading it will be equally informative for all of you. We’re also happy to announce there will be a Kindle edition available, along with various other electronic media. Get your copy from Wiley.com, Amazon.com, Barnes & Noble, and anywhere else awesome books are sold. *more or less… some sites list the publication date as early march, but the official street date is 2/21/2011

  Read the article

• Growing Into Enterprise Architecture

  - by pat.shepherd

  I am writing this post as I am in an Enterprise Architecture class, specifically on the Oracle Enterprise Architecture Framework (OEAF).  I have been a long believer that SOA’s key strength is that it is the first IT approach that blends or unifies business and technology.  That is a common view and is certainly valid but is not completely true (or at least accurate).  As my personal view of EA is growing, I realize more than ever that doing EA is FAR MORE than creating a reference architecture, creating a physical architecture or picking a technology to standardize on.  Those are parts of the puzzle but not the whole puzzle by any stretch. I am now a firm believer that the various EA frameworks out there provide the rigor and structure required to allow the bridging of business strategy / vision to IT strategy / vision. The flow goes something like this: Business Strategy –> Business / Application / Information / Technology Architecture –> SOA Reference Architecture –> SOA Functional Architecture.  Governance is imbued throughout to help map, measure and verify the business-to-IT coherence. With those in place, then (and only then) can SOA fulfill it’s potential to be more that an integration strategy, more than a reuse strategy; but also a foundation for tying the results of IT to business vision. Fortunately, EA is a an ongoing process that it is never too late to get started with an understanding of frameworks such as TOGAF, FEA, or OEAF.  Also, EA is never ending in that it always needs to be apply, even once a full-blown Enterprise Architecture is established it needs to be constantly evolved.  For those who are getting deeper into EA as a discipline, there is plenty runway to grow as your company/customer begins to look more seriously at EA. I will close with a pointer to a Great Book I have recently read on this subject: Enterprise Architecture as Strategy (http://www.amazon.com/Enterprise-Architecture-Strategy-Foundation-Execution/dp/1591398398/ref=sr_1_1?ie=UTF8&s=books&qid=1268842865&sr=1-1)

  Read the article

• SQL SERVER – Weekly Series – Memory Lane – #049

  - by Pinal Dave

  Here is the list of selected articles of SQLAuthority.com across all these years. Instead of just listing all the articles I have selected a few of my most favorite articles and have listed them here with additional notes below it. Let me know which one of the following is your favorite article from memory lane. 2007 Two Connections Related Global Variables Explained – @@CONNECTIONS and @@MAX_CONNECTIONS @@CONNECTIONS Returns the number of attempted connections, either successful or unsuccessful since SQL Server was last started. @@MAX_CONNECTIONS Returns the maximum number of simultaneous user connections allowed on an instance of SQL Server. The number returned is not necessarily the number currently configured. Query Editor – Microsoft SQL Server Management Studio This post may be very simple for most of the users of SQL Server 2005. Earlier this year, I have received one question many times – Where is Query Analyzer in SQL Server 2005? I wrote small post about it and pointed many users to that post – SQL SERVER – 2005 Query Analyzer – Microsoft SQL SERVER Management Studio. Recently I have been receiving similar question. OUTPUT Clause Example and Explanation with INSERT, UPDATE, DELETE SQL Server 2005 has a new OUTPUT clause, which is quite useful. OUTPUT clause has access to insert and deleted tables (virtual tables) just like triggers. OUTPUT clause can be used to return values to client clause. OUTPUT clause can be used with INSERT, UPDATE, or DELETE to identify the actual rows affected by these statements. OUTPUT clause can generate a table variable, a permanent table, or temporary table. Even though, @@Identity will still work with SQL Server 2005, however I find the OUTPUT clause very easy and powerful to use. Let us understand the OUTPUT clause using an example. Find Name of The SQL Server Instance Based on database server stored procedures has to run different logic. We came up with two different solutions. 1) When database schema is very much changed, we wrote completely new stored procedure and deprecated older version once it was not needed. 2) When logic depended on Server Name we used global variable @@SERVERNAME. It was very convenient while writing migrating script which depended on the server name for the same database. Explanation of TRY…CATCH and ERROR Handling With RAISEERROR Function One of the developers at my company thought that we can not use the RAISEERROR function in new feature of SQL Server 2005 TRY… CATCH. When asked for an explanation he suggested SQL SERVER – 2005 Explanation of TRY… CATCH and ERROR Handling article as excuse suggesting that I did not give example of RAISEERROR with TRY…CATCH. We all thought it was funny. Just to keep records straight, TRY… CATCH can sure use RAISEERROR function. Different Types of Cache Objects Serveral kinds of objects can be stored in the procedure cache: Compiled Plans: When the query optimizer finishes compiling a query plan, the principal output is compiled plan. Execution contexts: While executing a compiled plan, SQL Server has to keep track of information about the state of execution. Cursors: Cursors track the execution state of server-side cursors, including the cursor’s current location within a resultset. Algebrizer trees: The Algebrizer’s job is to produce an algebrizer tree, which represents the logic structure of a query. Open SSMS From Command Prompt – sqlwb.exe Example This article is written by request and suggestion of Sr. Web Developer at my organization. Due to the nature of this article most of the content is referred from Book On-Line. sqlwbcommand prompt utility which opens SQL Server Management Studio. Squib command does not run queries from the command prompt. sqlcmd utility runs queries from command prompt, read for more information. 2008 Puzzle – Solution – Computed Columns Datatype Explanation Just a day before I wrote article SQL SERVER – Puzzle – Computed Columns Datatype Explanation which was inspired by SQL Server MVP Jacob Sebastian. I suggest that before continuing this article read the original puzzle question SQL SERVER – Puzzle – Computed Columns Datatype Explanation.The question was if the computed column was of datatype TINYINT how to create a Computed Column of datatype INT? 2008 – Find If Index is Being Used in Database It is very often I get a query that how to find if any index is being used in the database or not. If any database has many indexes and not all indexes are used it can adversely affect performance. If the number of indices are higher it reduces the INSERT / UPDATE / DELETE operation but increase the SELECT operation. It is recommended to drop any unused indexes from table to improve the performance. 2009 Interesting Observation – Execution Plan and Results of Aggregate Concatenation Queries If you want to see what’s going on here, I think you need to shift your point of view from an implementation-centric view to an ANSI point of view. ANSI does not guarantee processing the order. Figure 2 is interesting, but it will be potentially misleading if you don’t understand the ANSI rule-set SQL Server operates under in most cases. Implementation thinking can certainly be useful at times when you really need that multi-million row query to finish before the backup fire off, but in this case, it’s counterproductive to understanding what is going on. SQL Server Management Studio and Client Statistics Client Statistics are very important. Many a times, people relate queries execution plan to query cost. This is not a good comparison. Both parameters are different, and they are not always related. It is possible that the query cost of any statement is less, but the amount of the data returned is considerably larger, which is causing any query to run slow. How do we know if any query is retrieving a large amount data or very little data? 2010 I encourage all of you to go through complete series and write your own on the subject. If you write an article and send it to me, I will publish it on this blog with due credit to you. If you write on your own blog, I will update this blog post pointing to your blog post. SQL SERVER – ORDER BY Does Not Work – Limitation of the View 1 SQL SERVER – Adding Column is Expensive by Joining Table Outside View – Limitation of the View 2 SQL SERVER – Index Created on View not Used Often – Limitation of the View 3 SQL SERVER – SELECT * and Adding Column Issue in View – Limitation of the View 4 SQL SERVER – COUNT(*) Not Allowed but COUNT_BIG(*) Allowed – Limitation of the View 5 SQL SERVER – UNION Not Allowed but OR Allowed in Index View – Limitation of the View 6 SQL SERVER – Cross Database Queries Not Allowed in Indexed View – Limitation of the View 7 SQL SERVER – Outer Join Not Allowed in Indexed Views – Limitation of the View 8 SQL SERVER – SELF JOIN Not Allowed in Indexed View – Limitation of the View 9 SQL SERVER – Keywords View Definition Must Not Contain for Indexed View – Limitation of the View 10 SQL SERVER – View Over the View Not Possible with Index View – Limitations of the View 11 SQL SERVER – Get Query Running in Session I was recently looking for syntax where I needed a query running in any particular session. I always remembered the syntax and ha d actually written it down before, but somehow it was not coming to mind quickly this time. I searched online and I ended up on my own article written last year SQL SERVER – Get Last Running Query Based on SPID. I felt that I am getting old because I forgot this really simple syntax. Find Total Number of Transaction on Interval In one of my recent Performance Tuning assignments I was asked how do someone know how many transactions are happening on a server during certain interval. I had a handy script for the same. Following script displays transactions happened on the server at the interval of one minute. You can change the WAITFOR DELAY to any other interval and it should work. 2011 Here are two DMV’s which are newly introduced in SQL Server 2012 and provides vital information about SQL Server. DMV – sys.dm_os_volume_stats – Information about operating system volume DMV – sys.dm_os_windows_info – Information about Operating System SQL Backup and FTP – A Quick and Handy Tool I have used this tool extensively since 2009 at numerous occasion and found it to be very impressive. What separates it from the crowd the most – it is it’s apparent simplicity and speed. When I install SQLBackupAndFTP and configure backups – all in 1 or 2 minutes, my clients are always impressed. Quick Note about JOIN – Common Questions and Simple Answers In this blog post we are going to talk about join and lots of things related to the JOIN. I recently started office hours to answer questions and issues of the community. I receive so many questions that are related to JOIN. I will share a few of the same over here. Most of them are basic, but note that the basics are of great importance. 2012 Importance of User Without Login Question: “In recent version of SQL Server we can create user without login. What is the use of it?” Great question indeed. Let me first attempt to answer this question but after reading my answer I need your help. I want you to help him as well with adding more value to it. Preserve Leading Zero While Coping to Excel from SSMS Earlier I wrote two articles about how to efficiently copy data from SSMS to Excel. Since I wrote that post there are plenty of interest generated on this subject. There are a few questions I keep on getting over this subject. One of the question is how to get the leading zero preserved while copying the data from SSMS to Excel. Well it is almost the same way as my earlier post SQL SERVER – Excel Losing Decimal Values When Value Pasted from SSMS ResultSet. The key here is in EXCEL and not in SQL Server. Solution – 2 T-SQL Puzzles – Display Star and Shortest Code to Display 1 Earlier on this blog we had asked two puzzles. The response from all of you is nothing but Amazing. I have received 350+ responses. Many are valid and many were indeed something I had not thought about it. I strongly suggest you read all the puzzles and their answers here - trust me if you start reading the comments you will not stop till you read every single comment. Seriously trust me on it. Personally I have learned a lot from it. Identify Most Resource Intensive Queries – SQL in Sixty Seconds #028 – Video http://www.youtube.com/watch?v=TvlYy-TGaaA Importance of User Without Login – T-SQL Demo Script Earlier I wrote a blog post about SQL SERVER – Importance of User Without Login and my friend and SQL Expert Vinod Kumar has written excellent follow up blog post about Contained Databases inside SQL Server 2012. Now lots of people asked me if I can also explain the same concept again so here is the small demonstration for it. Let me show you how login without user can help. Before we continue on this subject I strongly recommend that you read my earlier blog post here. In following demo I am going to demonstrate following situation. Login using the System Admin account Create a user without login Checking Access Impersonate the user without login Checking Access Revert Impersonation Give Permission to user without login Impersonate the user without login Checking Access Revert Impersonation Clean up Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Memory Lane, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

  Read the article

• Friday Fun: Wake Up the Box

  - by Mysticgeek

  Another Friday and it’s time to waste the rest of your Friday playing a  fun flash game online. Today we take a look at a relaxing physic based puzzle game called Wake Up the Box. Wake Up the Box This goal of this game is to wake up the box character by attaching parts of existing wood objects in each stage. You can start a new game or continue your progress from where you left off. At the beginning you get a tutorial showing what you need to do to wake the box. You get wood parts and can attach them to other wood pieces but not metal or brick. After successfully waking up Mr. Box, you can go to the next level or restart a level at any time if your having problems figuring out the puzzle. Each level gets more difficult and the puzzles are more challenging. Wake Up the Box is a relaxing and challenging game that will allow you to have fun, not working on TPS reports until the whistle blows. Play Wake Up the Box at FreeWebArcade Similar Articles Productive Geek Tips Stop the Mouse From Waking Up Your Computer from Sleep ModeFix "Sleep Mode Randomly Waking Up" Issue in Windows VistaStop Your Mouse from Waking Up Your Windows 7 ComputerPrevent Windows Asking for a Password on Wake Up from Sleep/StandbyUse Sleep.FM to Wake Up with the Web TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips DVDFab 6 Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 Microsoft’s “How Do I ?” Videos Home Networks – How do they look like & the problems they cause Check Your IMAP Mail Offline In Thunderbird Follow Finder Finds You Twitter Users To Follow Combine MP3 Files Easily QuicklyCode Provides Cheatsheets & Other Programming Stuff

  Read the article

• Is this high coupling?

  - by Bono

  Question I'm currently working a on an assignment for school. The assignment is to create a puzzle/calculator program in which you learn how to work with different datastructures (such as Stacks). We have generate infix math strings suchs as "1 + 2 * 3 - 4" and then turn them in to postfix math strings such as "1 2 + 3 * 4 -". In my book the author creates a special class for converting the infix notation to postfix. I was planning on using this but whilst I was about to implement it I was wondering if the following is what you would call "high coupling". I have read something about this (nothing that is taught in the book or anything) and was wondering about the aspect (since I still have to grasp it). Problem I have created a PuzzleGenerator class which generates the infix notation of the puzzle (or math string, whatever you want to call it) when it's instantiated. I was going to make a method getAnswer() in which I would instantiate the InToPost class (the class from the book) to convert the infix to postfox notation and then calculate the answer. But whilst doing this I thought: "Is using the InToPost class inside this method a form a high coupling, and would it be better to place this in a different method?" (such as a "convertPostfixToInfix" method, inside the PuzzleGenerator class) Thanks in advance.

  Read the article

• How do I produce "enjoyably" random, as opposed to pseudo-random?

  - by Hilton Campbell

  I'm making a game which presents a number of different kinds of puzzles in sequence. I choose each puzzle with a pseudorandom number. For each puzzle, there are a number of variations. I choose the variation with another pseudorandom number. And so on. The thing is, while this produces near-true randomness, this isn't what the player really wants. The player typically wants what they perceive to be and identify as random, but only if it doesn't tend to repeat puzzles. So, not really random. Just unpredictable. Giving it some thought, I can imagine hacky ways of doing it. For example, temporarily eliminating the most recent N choices from the set of possibilities when selecting a new choice. Or assigning every choice an equal probability, reducing a choice's probability to zero on selection, and then increasing all probabilities slowly with each selection. I assume there's an established way of doing this, but I just don't know the terminology so I can't find it. Anyone know? Or has anyone solved this in a pleasing way?

  Read the article

• touch detection of non-rectangular sprites (cocos2d)

  - by hogni89

  What is the correct way to implement a non-rectangular sprite in Cocos2d? I am working on a jigsaw puzzle. And therefor do our sprites have some strange forms (Jigsaw puzzle bricks). As of now, we have implemented the "detect" this way: - (void)selectSpriteForTouch:(CGPoint)touchLocation { CCSprite * newSprite = nil; // Loop array of sprites for (CCSprite *sprite in movableSprites) { // Check if sprite is hit. // TODO: Swap if with something better. if (CGRectContainsPoint(sprite.boundingBox, touchLocation)) { newSprite = sprite; break; } } if (newSprite != selSprite) { // Move along, nothing to see here // Not the problem } } - (BOOL)ccTouchBegan:(UITouch *)touch withEvent:(UIEvent *)event { CGPoint touchLocation = [self convertTouchToNodeSpace:touch]; [self selectSpriteForTouch:touchLocation]; return TRUE; } I know that the problem is in the keyword "sprite.boundingBox". Is there a better way of implementing this, OR is it a limit when using sprites based on .png's? If so, how should I proceed? I'm new to iPhone and game development :D

  Read the article

• SQL SERVER – Weekly Series – Memory Lane – #006

  - by pinaldave

  Here is the list of selected articles of SQLAuthority.com across all these years. Instead of just listing all the articles I have selected a few of my most favorite articles and have listed them here with additional notes below it. Let me know which one of the following is your favorite article from memory lane. 2006 This was my very first year of blogging so I was every day learning something new. As I have said many times, that blogging was never an intention. I had really not understood what exactly I am working on or beginning when I was beginning blogging in 2006. I had never knew that my life was going to change forever, once I started blogging. When I look back all of this year, I am happy that we are here together. 2007 IT Outsourcing to India – Top 10 Reasons Companies Outsource Outsourcing is about trust, collaboration and success. Helping other countries in need has been always the course of mankind, outsourcing is nothing different then that. With information technology and process improvements increasing the complexity, costs and skills required to accomplish routine tasks as well as challenging complex tasks, companies are outsourcing such tasks to providers who have the expertise to perform them at lower costs , with greater value and quality outcome. UDF – Remove Duplicate Chars From String This was a very interesting function I wrote in my early career. I am still using this function when I have to remove duplicate chars from strings. I have yet to come across a scenario where it does not work so I keep on using it till today. Please leave a comment if there is any better solution to this problem. FIX : Error : 3702 Cannot drop database because it is currently in use This is a very generic error when DROP Database is command is executed and the database is not dropped. The common mistake user is kept the connection open with this database and trying to drop the database. The database cannot be dropped if there is any other connection open along with it. It is always a good idea to take database in single user mode before dropping it. Here is the quick tutorial regarding how to bring the database in single user mode: Using T-SQL | Using SSMS. 2008 Install SQL Server 2008 – How to Upgrade to SQL Server 2008 – Installation Tutorial This was indeed one of the most popular articles in SQL Server 2008. Lots of people wanted to learn how to install SQL SErver 2008 but they were facing various issues while installation. I build this tutorial which becomes reference points for many. Default Collation of SQL Server 2008 What is the collation of SQL Server 2008 default installations? I often see this question confusing many experienced developers as well. Well the answer is in following image. Ahmedabad SQL Server User Group Meeting – November 2008 User group meetings are fun, now a days I am going to User Group meetings every week but there was a case when I have been just a beginner on this subject. The bug of the community was caught on me years ago when I started to present in Ahmedabad and Gandhinagar SQ LServer User Groups. 2009 Validate an XML document in TSQL using XSD My friend Jacob Sebastian wrote an excellent article on the subject XML and XSD. Because of the ‘eXtensible’ nature of XML (eXtensible Markup Language), often there is a requirement to restrict and validate the content of an XML document to a pre-defined structure and values. XSD (XML Schema Definition Language) is the W3C recommended language for describing and validating XML documents. SQL Server implements XSD as XML Schema Collections. Star Join Query Optimization At present, when queries are sent to very large databases, millions of rows are returned. Also the users have to go through extended query response times when joining multiple tables are involved with such queries. ‘Star Join Query Optimization’ is a new feature of SQL Server 2008 Enterprise Edition. This mechanism uses bitmap filtering for improving the performance of some types of queries by the effective retrieval of rows from fact tables. 2010 These puzzles are very interesting and intriguing – there was lots of interest on this subject. If you have free time this weekend. You may want to try them out. SQL SERVER – Challenge – Puzzle – Usage of FAST Hint (Solution)  SQL SERVER – Puzzle – Challenge – Error While Converting Money to Decimal (Solution)  SQL SERVER – Challenge – Puzzle – Why does RIGHT JOIN Exists (Open)  Additionally, I had great fun presenting SQL Server Performance Tuning seminar at fantastic locations in Hyderabad. Installing AdventeWorks Database This has been the most popular request I have received on my blog. Here is the quick video about how one can install AdventureWorks. 2011 Effect of SET NOCOUNT on @@ROWCOUNT There was an interesting incident once while I was presenting a session. I wrote a code and suddenly 10 hands went up in the air.  This was a bit surprise to me as I do not know why they all got alerted. I assumed that there should be something wrong with either project, screen or my display. However the real reason was very interesting – I suggest you read the complete blog post to understand this interesting scenario. Error: Deleting Offline Database and Creating the Same Name This is very interesting because once a user deletes the offline database the MDF and LDF file still exists and if the user attempts to create a new database with the same name it will give error. I found this very interesting and the blog explains the concept very quickly. Have you ever faced a similar situation? Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Memory Lane, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

  Read the article

• SQL SERVER – Weekly Series – Memory Lane – #004

  - by pinaldave

  Here is the list of curetted articles of SQLAuthority.com across all these years. Instead of just listing all the articles I have selected a few of my most favorite articles and have listed them here with additional notes below it. Let me know which one of the following is your favorite article from memory lane. 2006 Auto Generate Script to Delete Deprecated Fields in Current Database In early career everytime I have to drop a column, I had hard time doing it because I was scared what if that column was needed somewhere in the code. Due to this fear I never dropped any column. I just renamed the column. If the column which I renamed was needed afterwards it was very easy to rename it back again. However, it is not recommended to keep the deleted column renamed in the database. At every interval I used to drop the columns which was prefixed with specific word. This script is 6 years old but still works. Give it a look, I am open for improvements. 2007 Shrinking Truncate Log File – Log Full – Part 2 Shrinking database or mdf file is indeed bad thing and it creates lots of problems. However, once in a while there is legit requirement to shrink the log file – a very rare one. In the rare occasion shrinking or truncating the log file may be the only solution. However, one should make sure to take backup before and after the truncate or shrink as in case of a disaster they can be very useful. Remember that truncating log file will break the log chain and while restore it can create major issue. Anyway, use this feature with caution. 2008 Simple Use of Cursor to Print All Stored Procedures of Database Including Schema This is a very interesting requirement I used to face in my early career days, I needed to print all the Stored procedures of my database. Interesting enough I had written a cursor to do so. Today when I look back at this stored procedure, I believe there will be a much cleaner way to do the same task, however, I still use this SP quite often when I have to document all the stored procedures of my database. Interesting Observation about Order of Resultset without ORDER BY In industry many developers avoid using ORDER BY clause to display the result in particular order thinking that Index is enforcing the order. In this interesting example, I demonstrate that without using ORDER BY, same table and similar query can return different results. Query optimizer always returns results using any method which is optimized for performance. The learning is There is no order unless ORDER BY is used. 2009 Size of Index Table – A Puzzle to Find Index Size for Each Index on Table I asked this puzzle earlier where I asked how to find the Index size for each of the tables. The puzzle was very well received and lots of interesting answers were received. To answer this question I have written following blog posts. I suggest this weekend you try to solve this problem and see if you can come up with a better solution. If not, well here are the solutions. Solution 1 | Solution 2 | Solution 3 Understanding Table Hints with Examples Hints are options and strong suggestions specified for enforcement by the SQL Server query processor on DML statements. The hints override any execution plan the query optimizer might select for a query. The SQL Server Query optimizer is a very smart tool and it makes a better selection of execution plan. Suggesting hints to the Query Optimizer should be attempted when absolutely necessary and by experienced developers who know exactly what they are doing (or in development as a way to experiment and learn). Interesting Observation – TOP 100 PERCENT and ORDER BY I have seen developers and DBAs using TOP very causally when they have to use the ORDER BY clause. Theoretically, there is no need of ORDER BY in the view at all. All the ordering should be done outside the view and view should just have the SELECT statement in it. It was quite common that to save this extra typing by including ordering inside of the view. At several instances developers want a complete resultset and for the same they include TOP 100 PERCENT along with ORDER BY, assuming that this will simulate the SELECT statement with ORDER BY. 2010 SQLPASS Nov 8-11, 2010-Seattle – An Alternative Look at Experience In year 2010 I attended most prestigious SQL Server event SQLPASS between Nov 8-11, 2010 at Seattle. I have only one expression for the event - Best Summit Ever. Instead of writing about my usual routine or the event, I wrote about the interesting things I did and how I felt about it! When I go back and read it, I feel that this is the best event I attended in year 2010. Change Database Access to Single User Mode Using SSMS Image says all. 2011 SQL Server 2012 has introduced new analytic functions. These functions were long awaited and I am glad that they are now here. Before when any of this function was needed, people used to write long T-SQL code to simulate these functions. But now there’s no need of doing so. Having available native function also helps performance as well readability. Function SQLAuthority MSDN CUME_DIST CUME_DIST CUME_DIST FIRST_VALUE FIRST_VALUE FIRST_VALUE LAST_VALUE LAST_VALUE LAST_VALUE LEAD LEAD LEAD LAG LAG LAG PERCENTILE_CONT PERCENTILE_CONT PERCENTILE_CONT PERCENTILE_DISC PERCENTILE_DISC PERCENTILE_DISC PERCENT_RANK PERCENT_RANK PERCENT_RANK Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Memory Lane, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

  Read the article

• Question about spring manning-in-action

  - by Gandalf StormCrow

  I saw people asking about best book for learning spring, and I came across manning.spring in action was recommended most of the time so I decided to give it a go. The thing is the author offers some pretty reasonable explanations, puzzle by puzzle it gets in your head, than you just need to code it and you're done, you get it(this is how I work don't know about the others). When it comes to the code its very disapointing, I went trought the Knight example like 2 or 3 times by now and I see its incorrect in the book, I mean its hard already for people eager to learn and why not a note somewhere in the book like pseudo-code or something. The knight example in the first chapter is missing two classes QuestFailedException and HolyGrail I mean other people must have noticed this, why is everyone recommending this book without saying at least it has some errors(like many others do), was anyone actually been able to compile and this first chapter example?

  Read the article

• How to engineer features for machine learning

  - by Ivo Danihelka

  Do you have some advices or reading how to engineer features for a machine learning task? Good input features are important even for a neural network. The chosen features will affect the needed number of hidden neurons and the needed number of training examples. The following is an example problem, but I'm interested in feature engineering in general. A motivation example: What would be a good input when looking at a puzzle (e.g., 15-puzzle or Sokoban)? Would it be possible to recognize which of two states is closer to the goal?

  Read the article

• Can I replicate some of the optimisations done by the JVM by hand?

  - by Subb

  I'm working on a Sudoku solver at school and we're having a little performance contest. Right now, my algorithm is pretty fast on the first run (about 2.5ms), but even faster when I solve the same puzzle 10 000 times (about 0.5ms for each run). Those timing are, of course, depend of the puzzle being solved. I know the JVM do some optimization when a method is called multiple time, and this is what I suspect is happening. I don't think I can further optimize the algorithm itself (though I'll keep looking), so I was wondering if I could replicate some of the optimizations done by the JVM. Note : compiling to native code is not an option Thanks!

  Read the article

• jQuery/JSON/PHP failing

  - by user730936

  I am trying to call a php script that accepts JSON data, writes it into a file and returns simple text response using jQuery/AJAX call. jQuery code : $("input.callphp").click(function() { var url_file = myurl"; $.ajax({type : "POST", url : url_file, data : {'puzzle': 'Reset!'}, success : function(data){ alert("Success: " + data); }, error : function (data) { alert("Error: " + data); }, dataType : 'text' }); }); PHP Code : <?php $thefile = "new.json"; /* Our filename as defined earlier */ $towrite = $_POST["puzzle"]; /* What we'll write to the file */ $openedfile = fopen($thefile, "w"); fwrite($openedfile, $towrite); fclose($openedfile); echo "<br> <br>".$towrite; ?> However, the call is never a success and always gives an error with an alert "Error : [Object object]".

  Read the article

• SQL SERVER – Size of Index Table for Each Index – Solution 3 – Powershell

  - by pinaldave

  Laerte Junior If you are a Powershell user, the name of the Laerte Junior is not a new name. He is the one man with exceptional knowledge of Powershell. He is not only very knowledgeable, but also very kind and eager to those in need. I have been attempting to setup Powershell for many days, but constantly facing issues. I was not able to get going with this tool. Finally, yesterday I sent email to Laerte in response to his comment posted here. Within 5 minutes, Laerte came online and helped me with the solution. He spend nearly 15 minutes working along with me to solve my problem with installation. And yes, he did resolve it remotely without looking at my screen – What a skilled and exceptional person!! I will soon post a detail note about the issue I faced and resolved with the help of Laerte. Here is his solution to my earlier puzzle in his own words. Read the original puzzle here and Laerte’s solution from here. Hi Pinal, I do not say better, but maybe another approach to enthusiasts in powershell and SQLSPX library would be: 1 – All indexes in all tables and all databases Get-SqlDatabase -sqlserver “Yourserver” | Get-SqlTable | Get-SqlIndex | Format-table Server,dbname,schema,table,name,id,spaceused 2 – All Indexes in all tables and specific database Get-SqlDatabase -sqlserver “Yourserver” “Yourdb” | Get-SqlTable | Get-SqlIndex | Format-table Server,dbname,schema,table,name,id,spaceused 3 – All Indexes in specific table and database Get-SqlDatabase -sqlserver “Yourserver” “Yourdb” | Get-SqlTable “YourTable” | Get-SqlIndex | Format-table Server,dbname,schema,table,name,id,spaceused and to output to txt.. pipe Out-File Get-SqlDatabase -sqlserver “Yourserver” | Get-SqlTable | Get-SqlIndex | Format-table Server,dbname,schema,table,name,id,spaceused | out-file c:\IndexesSize.txt If you have one txt with all your servers, can be for all of them also. Lets say you have all your servers in servers.txt: something like NameServer1 NameServer2 NameServer3 NameServer4 We could Use : foreach ($Server in Get-content c:\temp\servers.txt) { Get-SqlDatabase -sqlserver $Server | Get-SqlTable | Get-SqlIndex | Format-table Server,dbname,schema,table,name,id,spaceused } :) After fixing my issue with Powershell, I ran Laerte‘s second suggestion – “All Indexes in all tables and specific database” and found the following accurate output. Click to Enlarge Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Pinal Dave, SQL, SQL Authority, SQL Index, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, T SQL, Technology Tagged: Powershell

  Read the article

• SQL SERVER – Size of Index Table for Each Index – Solution 3 – Powershell

  - by pinaldave

  Laerte Junior If you are a Powershell user, the name of the Laerte Junior is not a new name. He is the one man with exceptional knowledge of Powershell. He is not only very knowledgeable, but also very kind and eager to those in need. I have been attempting to setup Powershell for many days, but constantly facing issues. I was not able to get going with this tool. Finally, yesterday I sent email to Laerte in response to his comment posted here. Within 5 minutes, Laerte came online and helped me with the solution. He spend nearly 15 minutes working along with me to solve my problem with installation. And yes, he did resolve it remotely without looking at my screen – What a skilled and exceptional person!! I will soon post a detail note about the issue I faced and resolved with the help of Laerte. Here is his solution to my earlier puzzle in his own words. Read the original puzzle here and Laerte’s solution from here. Hi Pinal, I do not say better, but maybe another approach to enthusiasts in powershell and SQLSPX library would be: 1 – All indexes in all tables and all databases Get-SqlDatabase -sqlserver “Yourserver” | Get-SqlTable | Get-SqlIndex | Format-table Server,dbname,schema,table,name,id,spaceused 2 – All Indexes in all tables and specific database Get-SqlDatabase -sqlserver “Yourserver” “Yourdb” | Get-SqlTable | Get-SqlIndex | Format-table Server,dbname,schema,table,name,id,spaceused 3 – All Indexes in specific table and database Get-SqlDatabase -sqlserver “Yourserver” “Yourdb” | Get-SqlTable “YourTable” | Get-SqlIndex | Format-table Server,dbname,schema,table,name,id,spaceused and to output to txt.. pipe Out-File Get-SqlDatabase -sqlserver “Yourserver” | Get-SqlTable | Get-SqlIndex | Format-table Server,dbname,schema,table,name,id,spaceused | out-file c:\IndexesSize.txt If you have one txt with all your servers, can be for all of them also. Lets say you have all your servers in servers.txt: something like NameServer1 NameServer2 NameServer3 NameServer4 We could Use : foreach ($Server in Get-content c:\temp\servers.txt) { Get-SqlDatabase -sqlserver $Server | Get-SqlTable | Get-SqlIndex | Format-table Server,dbname,schema,table,name,id,spaceused } :) After fixing my issue with Powershell, I ran Laerte‘s second suggestion – “All Indexes in all tables and specific database” and found the following accurate output. Click to Enlarge Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Pinal Dave, SQL, SQL Authority, SQL Index, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, T SQL, Technology Tagged: Powershell

  Read the article

• Observations in Migrating from JavaFX Script to JavaFX 2.0

  - by user12608080

  Observations in Migrating from JavaFX Script to JavaFX 2.0 Introduction Having been available for a few years now, there is a decent body of work written for JavaFX using the JavaFX Script language. With the general availability announcement of JavaFX 2.0 Beta, the natural question arises about converting the legacy code over to the new JavaFX 2.0 platform. This article reflects on some of the observations encountered while porting source code over from JavaFX Script to the new JavaFX API paradigm. The Application The program chosen for migration is an implementation of the Sudoku game and serves as a reference application for the book JavaFX – Developing Rich Internet Applications. The design of the program can be divided into two major components: (1) A user interface (ideally suited for JavaFX design) and (2) the puzzle generator. For the context of this article, our primary interest lies in the user interface. The puzzle generator code was lifted from a sourceforge.net project and is written entirely in Java. Regardless which version of the UI we choose (JavaFX Script vs. JavaFX 2.0), no code changes were required for the puzzle generator code. The original user interface for the JavaFX Sudoku application was written exclusively in JavaFX Script, and as such is a suitable candidate to convert over to the new JavaFX 2.0 model. However, a few notable points are worth mentioning about this program. First off, it was written in the JavaFX 1.1 timeframe, where certain capabilities of the JavaFX framework were as of yet unavailable. Citing two examples, this program creates many of its own UI controls from scratch because the built-in controls were yet to be introduced. In addition, layout of graphical nodes is done in a very manual manner, again because much of the automatic layout capabilities were in flux at the time. It is worth considering that this program was written at a time when most of us were just coming up to speed on this technology. One would think that having the opportunity to recreate this application anew, it would look a lot different from the current version. Comparing the Size of the Source Code An attempt was made to convert each of the original UI JavaFX Script source files (suffixed with .fx) over to a Java counterpart. Due to language feature differences, there are a small number of source files which only exist in one version or the other. The table below summarizes the size of each of the source files. JavaFX Script source file Number of Lines Number of Character JavaFX 2.0 Java source file Number of Lines Number of Characters ArrowKey.java 6 72 Board.fx 221 6831 Board.java 205 6508 BoardNode.fx 446 16054 BoardNode.java 723 29356 ChooseNumberNode.fx 168 5267 ChooseNumberNode.java 302 10235 CloseButtonNode.fx 115 3408 CloseButton.java 99 2883 ParentWithKeyTraversal.java 111 3276 FunctionPtr.java 6 80 Globals.java 20 554 Grouping.fx 8 140 HowToPlayNode.fx 121 3632 HowToPlayNode.java 136 4849 IconButtonNode.fx 196 5748 IconButtonNode.java 183 5865 Main.fx 98 3466 Main.java 64 2118 SliderNode.fx 288 10349 SliderNode.java 350 13048 Space.fx 78 1696 Space.java 106 2095 SpaceNode.fx 227 6703 SpaceNode.java 220 6861 TraversalHelper.fx 111 3095 Total 2,077 79,127 2531 87,800 A few notes about this table are in order: The number of lines in each file was determined by running the Unix ‘wc –l’ command over each file. The number of characters in each file was determined by running the Unix ‘ls –l’ command over each file. The examination of the code could certainly be much more rigorous. No standard formatting was performed on these files.  All comments however were deleted. There was a certain expectation that the new Java version would require more lines of code than the original JavaFX script version. As evidenced by a count of the total number of lines, the Java version has about 22% more lines than its FX Script counterpart. Furthermore, there was an additional expectation that the Java version would be more verbose in terms of the total number of characters.  In fact the preceding data shows that on average the Java source files contain fewer characters per line than the FX files.  But that's not the whole story.  Upon further examination, the FX Script source files had a disproportionate number of blank characters.  Why?  Because of the nature of how one develops JavaFX Script code.  The object literal dominates FX Script code.  Its not uncommon to see object literals indented halfway across the page, consuming lots of meaningless space characters. RAM consumption Not the most scientific analysis, memory usage for the application was examined on a Windows Vista system by running the Windows Task Manager and viewing how much memory was being consumed by the Sudoku version in question. Roughly speaking, the FX script version, after startup, had a RAM footprint of about 90MB and remained pretty much the same size. The Java version started out at about 55MB and maintained that size throughout its execution. What About Binding? Arguably, the most striking observation about the conversion from JavaFX Script to JavaFX 2.0 concerned the need for data synchronization, or lack thereof. In JavaFX Script, the primary means to synchronize data is via the bind expression (using the “bind” keyword), and perhaps to a lesser extent it’s “on replace” cousin. The bind keyword does not exist in Java, so for JavaFX 2.0 a Data Binding API has been introduced as a replacement. To give a feel for the difference between the two versions of the Sudoku program, the table that follows indicates how many binds were required for each source file. For JavaFX Script files, this was ascertained by simply counting the number of occurrences of the bind keyword. As can be seen, binding had been used frequently in the JavaFX Script version (and does not take into consideration an additional half dozen or so “on replace” triggers). The JavaFX 2.0 program achieves the same functionality as the original JavaFX Script version, yet the equivalent of binding was only needed twice throughout the Java version of the source code. JavaFX Script source file Number of Binds JavaFX Next Java source file Number of “Binds” ArrowKey.java 0 Board.fx 1 Board.java 0 BoardNode.fx 7 BoardNode.java 0 ChooseNumberNode.fx 11 ChooseNumberNode.java 0 CloseButtonNode.fx 6 CloseButton.java 0 CustomNodeWithKeyTraversal.java 0 FunctionPtr.java 0 Globals.java 0 Grouping.fx 0 HowToPlayNode.fx 7 HowToPlayNode.java 0 IconButtonNode.fx 9 IconButtonNode.java 0 Main.fx 1 Main.java 0 Main_Mobile.fx 1 SliderNode.fx 6 SliderNode.java 1 Space.fx 0 Space.java 0 SpaceNode.fx 9 SpaceNode.java 1 TraversalHelper.fx 0 Total 58 2 Conclusions As the JavaFX 2.0 technology is so new, and experience with the platform is the same, it is possible and indeed probable that some of the observations noted in the preceding article may not apply across other attempts at migrating applications. That being said, this first experience indicates that the migrated Java code will likely be larger, though not extensively so, than the original Java FX Script source. Furthermore, although very important, it appears that the requirements for data synchronization via binding, may be significantly less with the new platform.

  Read the article

• SQL SERVER – Tricks to Replace SELECT * with Column Names – SQL in Sixty Seconds #017 – Video

  - by pinaldave

  You might have heard many times that one should not use SELECT * as there are many disadvantages to the usage of the SELECT *. I also believe that there are always rare occasion when we need every single column of the query. In most of the cases, we only need a few columns of the query and we should retrieve only those columns. SELECT * has many disadvantages. Let me list a few and remaining you can add as a comment.  Retrieves unnecessary columns and increases network traffic When a new columns are added views needs to be refreshed manually Leads to usage of sub-optimal execution plan Uses clustered index in most of the cases instead of using optimal index It is difficult to debug. There are two quick tricks I have discussed in the video which explains how users can avoid using SELECT * but instead list the column names. 1) Drag the columns folder from SQL Server Management Studio to Query Editor 2) Right Click on Table Name >> Script TAble AS >> SELECT To… >> Select option It is extremely easy to list the column names in the table. In today’s sixty seconds video, you will notice that I was able to demonstrate both the methods very quickly. From now onwards there should be no excuse for not listing ColumnName. Let me ask a question back – is there ever a reason to SELECT *? If yes, would you please share that as a comment. More on SELECT *: SQL SERVER – Solution – Puzzle – SELECT * vs SELECT COUNT(*) SQL SERVER – Puzzle – SELECT * vs SELECT COUNT(*) SQL SERVER – SELECT vs. SET Performance Comparison I encourage you to submit your ideas for SQL in Sixty Seconds. We will try to accommodate as many as we can. If we like your idea we promise to share with you educational material. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Database, Pinal Dave, PostADay, SQL, SQL Authority, SQL in Sixty Seconds, SQL Query, SQL Scripts, SQL Server, SQL Server Management Studio, SQL Tips and Tricks, T SQL, Technology, Video

  Read the article

• Separating physics and game logic from UI code

  - by futlib

  I'm working on a simple block-based puzzle game. The game play consists pretty much of moving blocks around in the game area, so it's a trivial physics simulation. My implementation, however, is in my opinion far from ideal and I'm wondering if you can give me any pointers on how to do it better. I've split the code up into two areas: Game logic and UI, as I did with a lot of puzzle games: The game logic is responsible for the general rules of the game (e.g. the formal rule system in chess) The UI displays the game area and pieces (e.g. chess board and pieces) and is responsible for animations (e.g. animated movement of chess pieces) The game logic represents the game state as a logical grid, where each unit is one cell's width/height on the grid. So for a grid of width 6, you can move a block of width 2 four times until it collides with the boundary. The UI takes this grid, and draws it by converting logical sizes into pixel sizes (that is, multiplies it by a constant). However, since the game has hardly any game logic, my game logic layer [1] doesn't have much to do except collision detection. Here's how it works: Player starts to drag a piece UI asks game logic for the legal movement area of that piece and lets the player drag it within that area Player lets go of a piece UI snaps the piece to the grid (so that it is at a valid logical position) UI tells game logic the new logical position (via mutator methods, which I'd rather avoid) I'm not quite happy with that: I'm writing unit tests for my game logic layer, but not the UI, and it turned out all the tricky code is in the UI: Stopping the piece from colliding with others or the boundary and snapping it to the grid. I don't like the fact that the UI tells the game logic about the new state, I would rather have it call a movePieceLeft() method or something like that, as in my other games, but I didn't get far with that approach, because the game logic knows nothing about the dragging and snapping that's possible in the UI. I think the best thing to do would be to get rid of my game logic layer and implement a physics layer instead. I've got a few questions regarding that: Is such a physics layer common, or is it more typical to have the game logic layer do this? Would the snapping to grid and piece dragging code belong to the UI or the physics layer? Would such a physics layer typically work with pixel sizes or with some kind of logical unit, like my game logic layer? I've seen event-based collision detection in a game's code base once, that is, the player would just drag the piece, the UI would render that obediently and notify the physics system, and the physics system would call a onCollision() method on the piece once a collision is detected. What is more common? This approach or asking for the legal movement area first? [1] layer is probably not the right word for what I mean, but subsystem sounds overblown and class is misguiding, because each layer can consist of several classes.

  Read the article

• optimizing graphics for iOS flash game

  - by 1GR3

  Friend of mine and me are working on a flash developed iOS (and later Android) puzzle board game. He's a programmer and I'm a designer/developer so (no surprise) we have a different points of view. anyway, he's method: make small tiles (100x100px) in photoshop join them into the board and then in flash apply effects to the board to avoid repetition (80's not in the good way) my method: precompose the whole board (960x640px+bleed) in photoshop and than mask active and inactive areas in flash what do you think? thank you in advance!

  Read the article

• Learning how to integrate JavaScript with other languages

  - by beacon

  After learning JavaScript syntax, what are some good resources for learning about integrating JavaScript with other languages (HTML, XML, CSS, PHP) to create real, useful applications? I'm most interested in reading articles or other people's code - not so interested in books. Basically, I'm looking to move from programming puzzle-solvers to programming complex applications and could use some advice.

  Read the article

• Search Engine Optimization: Selecting and Embedding Keywords

  Search engine optimization (SEO) helps search engines display your web site in their search results. Keywords are an important piece of the SEO puzzle.

  Read the article

• andengine - how to make the game wait for an animation to finish?

  - by petervaz

  I'm teaching myself andengine while trying to make a match-3 puzzle, so far I have a grid of gems that I populate and can move then around. Matching gems and new gems falling is working already. My problem is that the game keeps flowing while animations runs. How can I make the flow suspend until movement is done? I use entity modifiers for the gems animations. MoveYModifier for the fall and PathModifier for the swap.

  Read the article

• Randomly generate directed graph on a grid

  - by Talon876

  I am trying to randomly generate a directed graph for the purpose of making a puzzle game similar to the ice sliding puzzles from Pokemon. This is essentially what I want to be able to randomly generate: http://bulbanews.bulbagarden.net/wiki/Crunching_the_numbers:_Graph_theory. I need to be able to limit the size of the graph in an x and y dimension. In the example given in the link, it would be restricted to an 8x4 grid. The problem I am running into is not randomly generating the graph, but randomly generating a graph, which I can properly map out in a 2d space, since I need something (like a rock) on the opposite side of a node, to make it visually make sense when you stop sliding. The problem with this is that sometimes the rock ends up in the path between two other nodes or possibly on another node itself, which causes the entire graph to become broken. After discussing the problem with a few people I know, we came to a couple of conclusions that may lead to a solution. Including the obstacles in the grid as part of the graph when constructing it. Start out with a fully filled grid and just draw a random path and delete out blocks that will make that path work. The problem then becomes figuring out which ones to delete to avoid introducing an additional, shorter path. We were also thinking a dynamic programming algorithm may be beneficial, though none of us are too skilled with creating dynamic programming algorithms from nothing. Any ideas or references about what this problem is officially called (if it's an official graph problem) would be most helpful. Here are some examples of what I have accomplished so far by just randomly placing blocks and generating the navigation graph from the chosen start/finish. The idea (as described in the previous link) is you start at the green S and want to get to the green F. You do this by moving up/down/left/right and you continue moving in the direction chosen until you hit a wall. In these pictures, grey is a wall, white is the floor, and the purple line is the minimum length from start to finish, and the black lines and grey dots represented possible paths. Here are some bad examples of randomly generated graphs: http://i.stack.imgur.com/9uaM6.png Here are some good examples of randomly generated (or hand tweaked) graphs: i.stack.imgur.com/uUGeL.png (can't post another link, sorry) I've also seemed to notice the more challenging ones when actually playing this as a puzzle are ones which have lots of high degree nodes along the minimum path.

  Read the article

< Previous Page | 5 6 7 8 9 10 11 12 13 14 15 16  | Next Page >