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  • Mysql - Help me alter this query to apply AND logic instead of OR in searching?

    - by sandeepan-nath
    First execute these tables and data dumps :- CREATE TABLE IF NOT EXISTS `Tags` ( `id_tag` int(10) unsigned NOT NULL auto_increment, `tag` varchar(255) default NULL, PRIMARY KEY (`id_tag`), UNIQUE KEY `tag` (`tag`), KEY `id_tag` (`id_tag`), KEY `tag_2` (`tag`), KEY `tag_3` (`tag`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1 AUTO_INCREMENT=18 ; INSERT INTO `Tags` (`id_tag`, `tag`) VALUES (1, 'key1'), (2, 'key2'); CREATE TABLE IF NOT EXISTS `Tutors_Tag_Relations` ( `id_tag` int(10) unsigned NOT NULL default '0', `id_tutor` int(10) default NULL, KEY `Tutors_Tag_Relations` (`id_tag`), KEY `id_tutor` (`id_tutor`), KEY `id_tag` (`id_tag`) ) ENGINE=InnoDB DEFAULT CHARSET=latin1; INSERT INTO `Tutors_Tag_Relations` (`id_tag`, `id_tutor`) VALUES (1, 1), (2, 1); The following query finds all the tutors from Tutors_Tag_Relations table which have reference to at least one of the terms "key1" or "key2". SELECT td . * FROM Tutors_Tag_Relations AS td INNER JOIN Tags AS t ON t.id_tag = td.id_tag WHERE t.tag LIKE "%key1%" OR t.tag LIKE "%key2%" Group by td.id_tutor LIMIT 10 Please help me modify this query so that it returns all the tutors from Tutors_Tag_Relations table which have reference to both the terms "key1" and "key2" (AND logic instead of OR logic). Please suggest an optimized query considering huge number of data records (the query should NOT individually fetch two sets of tutors matching each keyword and then find the intersection).

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  • Arrays not counting correctly

    - by Nick Gibson
    I know I was just asking a question earlier facepalm This is in Java coding by the way. Well after everyones VERY VERY helpful advice (thank you guys alot) I managed to get over half of the program running how I wanted. Everything is pointing in the arrays where I want them to go. Now I just need to access the arrays so that It prints the correct information randomly. This is the current code that im using: http://pastebin.org/301483 The specific code giving me problems is this: long aa; int abc; for (int i = 0; i < x; i++) { aa = Math.round(Math.random()*10); String str = Long.toString(aa); abc = Integer.parseInt(str); String[] userAnswer = new String[x]; if(abc > x) { JOptionPane.showMessageDialog(null,"Number is too high. \nNumber Generator will reset."); break; } userAnswer[i] = JOptionPane.showInputDialog(null,"Question "+quesNum+"\n"+questions[abc]+"\n\nA: "+a[abc]+"\nB: "+b[abc]+"\nC: "+c[abc]+"\nD: "+d[abc]); answer = userAnswer[i].compareTo(answers[i]); if(answer == 0) { JOptionPane.showMessageDialog(null,"Correct. \nThe Correct Answer is "+answers[abc]+""+i); } else { JOptionPane.showMessageDialog(null,"Wrong. \n The Correct Answer is "+answers[abc]+""+i); }//else

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  • Why would one want to use the public constructors on Boolean and similar immutable classes?

    - by Robert J. Walker
    (For the purposes of this question, let us assume that one is intentionally not using auto(un)boxing, either because one is writing pre-Java 1.5 code, or because one feels that autounboxing makes it too easy to create NullPointerExceptions.) Take Boolean, for example. The documentation for the Boolean(boolean) constructor says: Note: It is rarely appropriate to use this constructor. Unless a new instance is required, the static factory valueOf(boolean) is generally a better choice. It is likely to yield significantly better space and time performance. My question is, why would you ever want to get a new instance in the first place? It seems like things would be simpler if constructors like that were private. For example, if they were, you could write this with no danger (even if myBoolean were null): if (myBoolean == Boolean.TRUE) It'd be safe because all true Booleans would be references to Boolean.TRUE and all false Booleans would be references to Boolean.FALSE. But because the constructors are public, someone may have used them, which means that you have to write this instead: if (Boolean.TRUE.equals(myBoolean)) But where it really gets bad is when you want to check two Booleans for equality. Something like this: if (myBooleanA == myBooleanB) ...becomes this: if ( (myBooleanA == null && myBooleanB == null) || (myBooleanA == null && myBooleanA.equals(myBooleanB)) ) I can't think of any reason to have separate instances of these objects which is more compelling than not having to do the nonsense above. What say you?

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  • What are the interets of synthetic methods?

    - by romaintaz
    Problem One friend suggested an interesting problem. Given the following code: public class OuterClass { private String message = "Hello World"; private class InnerClass { private String getMessage() { return message; } } } From an external class, how may I print the message variable content? Of course, changing the accessibility of methods or fields is not allowed. (the source here, but it is a french blog) Solution The code to solve this problem is the following: try { Method m = OuterClass.class.getDeclaredMethod("access$000", OuterClass.class); OuterClass outerClass = new OuterClass(); System.out.println(m.invoke(outerClass, outerClass)); } catch (Exception e) { e.printStackTrace(); } Note that the access$000 method name is not really standard (even if this format is the one that is strongly recommanded), and some JVM will name this method access$0. Thus, a better solution is to check for synthetic methods: Method method = null; int i = 0; while ((method == null) && (i < OuterClass.class.getDeclaredMethods().length)) { if (OuterClass.class.getDeclaredMethods()[i].isSynthetic()) { method = OuterClass.class.getDeclaredMethods()[i]; } i++; } if (method != null) { try { System.out.println(method.invoke(null, new OuterClass())); } catch (Exception e) { e.printStackTrace(); } } So the interesting point in this problem is to highlight the use of synthetic methods. With these methods, I can access a private field as it was done in the solution. Of course, I need to use reflection, and I think that the use of this kind of thing can be quite dangerous... Question What is the interest - for me, as a developer - of a synthetic method? What can be a good situation where using the synthetic can be useful?

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  • About Web service ,how to use Ajax to call a specific member function of a class?

    - by Liu chwen
    I'm trying to build a web service by PHP. In my case, I called the getINFO(), but the return value on client side always null. Have no idea to solve this problem.. Here's the SOAPserver code(WS.WEB_s.php): require("WEB_s.php"); ini_set("soap.wsdl_cache_enabled", 0); $server = new SoapServer('wsdl/WEB_s.wsdl'); $server->setClass("WEB_s"); $server->handle(); Where the main Class is(WEB_s.php): final class WEB_s { public function getINFO(){ $JsonOutput = '{"key":"value",...}'; return $JsonOutput; } public function setWAN($setCommand,$newConfigfilePath){ $bOutput; return $bOutput; } } And Client side: $(document).ready(function(){ $('#qqq').button().click(function(){ var soapMessage = LoginSoap($('#uid').val(),$('#pwd').val()); alert('soapMessage'); $.ajax({ //url: 'libraries/WS.WEB_s.php/WEB_s/getINFO',//success , return null //url: 'libraries/WS.WEB_s.php/', //success , return null url: 'libraries/WS.WEB_s.php/getINFO',//success , return null type: 'GET', timeout: (10* 1000), contentType: "text/xml", dataType: "xml", success: function( data,textStatus,jqXHR){ alert('Server success(' + data+')('+ textStatus + ')(' + jqXHR + ')'); }, error: function (request, status, error) { alert('Server Error(' + status+')->'+error); }, complete: function (jqXHR, textStatus) { alert('Server success(' + jqXHR+')('+ textStatus + ')'); } }); }); }); The following is the corresponding WSDL file : http://codepaste.net/95wq9b

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  • Sinatra Routing Exceptions

    - by Ethan Turkeltaub
    I want to be able to do the following: get '/:slug' do haml :page end get '/administration' do haml :admin end Is there a way that I can have get '/:slug' do have an exception for /administration? I realize you can do this with if else statements: get '/:slug' do if params[:slug] == 'administration' haml :admin else haml :page end end But that isn't very clean looking. Is there a way to have an exception to routes?

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  • referencing (this) in a function

    - by Sara Chipps
    I have elements being generated by dynamic html, I would like to reference the particular href that is calling the function when one of many may be calling it. <a href="javascript:Foo(this)">Link</a> Does not work when I try to reference $(this). Is there another way to do this or do I have to make dynamic ids?

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  • extract transform load

    - by mitch
    Wikipedia defines a 'typical' ETL cycle as : Cycle initiation Build reference data Extract (from sources) Validate Transform (clean, apply business rules, check for data integrity, create aggregates or disaggregates) Stage (load into staging tables, if used) Audit reports (for example, on compliance with business rules. Also, in case of failure, helps to diagnose/repair) Publish (to target tables) Archive Clean up ..What is meant by 'Build reference data'?

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  • Django's local web server works, but not apaches

    - by tipu
    I've made no changes to the django project after running django-admin.py startproject Twingle When I run the local web server using python manage.py runserver, I can view the splash page telling me everything is working fine. But when I try to visit that project through apache, it fails. You can see the error at http://djaffry.selfip.com:8080/ The exception: Exception Value: No module named Twingle.urls (the project is Twingle)

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  • removing items from a generic List<t>

    - by frosty
    I have the following method, I wish to remove items from my collection that match the product Id. Seems fairly straight forward, but i get an exception. Basically my collection is getting out of sync. So what is the best way to remove an item from a collection. public void RemoveOrderItem(Model.Order currentOrder, int productId) { foreach (var orderItem in currentOrder.OrderItems) { if (orderItem.Product.Id == productId) { currentOrder.OrderItems.Remove(orderItem); } } } Exception Details: System.InvalidOperationException: Collection was modified; enumeration operation may not execute

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  • jQuery .die isnt killing an attached event?

    - by adam
    Hi I've just started experimenting with .live and .die and having some great results but one thing isn't working. I've been tinkering with firebugs console to try out my written code live to see if i can figure out the reason why .die isn't killing off an attached event. First if i do this //attach ajax submission $('a[href$=edit]').live("click", function(event) { $.get($(this).attr("href"), null, null); return false; }); Then as expected when I click on a link the ajax fires off and my server side code injects a form for inline editing. But sometimes I want to disable this behaviour and also make the link unclickable so I do the following //unbind ajax form creation when we click on a link, then disable its semantic behaviour $('a[href$=edit]').die("click").click( function(){ return false; } ); which works but if then try to remove this and restore that ajax goodness with the code below it doesn't work, Instead the link remains unclickable. I cant figure out why? Can anyone help? //remove any previous events from the links $('a[href$=edit]').die(); //attach ajax submission $('a[href$=edit]').live("click", function(event) { $.get($(this).attr("href"), null, null); return false; });

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  • i got this error when i run my application?

    - by Surya sasidhar
    hi, when i run my application i got this error like... Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. Exception Details: System.Security.Policy.PolicyException: Required permissions cannot be acquired. can you help me..

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  • Is it OK to set state within Event Raising methods?

    - by Greg
    I ran across this pattern in the code of a library I'm using. It sets state within the event raising method, but only if the event is not null. protected virtual void OnMyEvent(EventArgs e) { if(MyEvent != null) { State = "Executing"; // Only sets state if MyEvent != null. MyEvent(this,e); } } Which means that the state is not set when overriding the method: protected override void OnMyEvent(EventArgs e) { base.OnMyEvent(e); Debug.Assert( State == "Executing" ); // This fails } but is only set when handling the event: foo.MyEvent += (o, args) => Debug.Assert(State == "Executing"); // This passes Setting state within the if(MyEvent != null) seems like bad form, but I've checked the Event Design Guidelines and it doesn't mention this. Do you think this code is incorrect? If so, why? (Reference to design guidelines would be helpful). Edit for Context: It's a Control, I'm trying to create subclass of it, and the state that it's setting is calling EnsureChildControls() conditionally based upon there being an event handler. I can call EnsureChildControls() myself, but I consider that something of a hack.

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  • File writing problem on Windows 7 Professional in c#

    - by Ummar
    I have an application in C# which I write some data to file. I am facing the problem on windows 7 professional that when I write data to C:\ProgramData, Access denied acception is thrown. If I login from an administrator account this issue vanishes, and if I login from some other account who have administrative previlages this issue comes up. This issue is only produces on windows 7 professional, it is working fine on all other flavors of windows 7 as well as windows vista. try { XmlTextWriter myXmlTextWriter = new XmlTextWriter("Configuration.xml", null); myXmlTextWriter.Formatting = Formatting.Indented; myXmlTextWriter.WriteStartDocument(true); myXmlTextWriter.WriteDocType("ApplicationConfigurations", null, null, null); ////myXmlTextWriter.WriteComment("This file represents another fragment of a book store inventory database"); myXmlTextWriter.WriteStartElement("Configuration"); myXmlTextWriter.WriteElementString("firstElement", pe.ToString()); myXmlTextWriter.WriteEndElement(); myXmlTextWriter.WriteEndDocument(); myXmlTextWriter.Flush(); myXmlTextWriter.Close(); }catch(Exception e) { //Exception is thrown in Win7 professional }

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  • How to display an image(all major formats), selected by JFileChooser in java

    - by Tushar Maroo
    I am developing an image editing app, so want to display an image selected by JFileChooser, so what would be best approach so that it can display all formats jpg, png, gif etc. OpenButton is used for invocation of filechooser. private void OpenActionPerformed(java.awt.event.ActionEvent evt) { int returnVal = fileChosser.showOpenDialog(this); if (returnVal == JFileChooser.APPROVE_OPTION) { File file = fileChosser.getSelectedFile(); // What to do with the file // I want code for this part try { //code that might create an exception } catch (Exception e1) { e.printStackTrace(); } } }

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  • C#, cannot understand this error?

    - by 5YrsLaterDBA
    I am using VS2008. I have a project, SystemSoftware project, connect with a database and we are using L2E. I have a RuntimeInfo class which contains some shared information there. It looks like this: public class RuntimeInfo { public const int PWD_ExpireDays = 30; private static RuntimeInfo thisObj = new RuntimeInfo(); public static string AndeDBConnStr = ConfigurationManager.ConnectionStrings["AndeDBEntities"].ConnectionString; private RuntimeInfo() { } /// <summary> /// /// </summary> /// <returns>Return this singleton object</returns> public static RuntimeInfo getRuntimeInfo() { return thisObj; } } Now I added a helper project, AndeDataViewer, to the solution which creates a simple UI to display data from the database for testing/verification purpose. I don't want to create another set of Entity Data Model in the helper project. I just added all related files as a link in the new helper project. In the AndeDataViewer project, I get the connection string from above RuntimeInfo class which is a class from my SystemSoftware project as a linked file. The code in AndeDataViewer is like this: public class DbAccess : IDisposable { private String connStr = String.Empty; public DbAccess() { connStr = RuntimeInfo.AndeDBConnStr; } } My SystemSoftware works fine that means the RuntimeInfo class has no problem there. But when I run my AndeDataViewer, the statement inside above constructor, connStr = RuntimeInfo.AndeDBConnStr; , throws an exception. The exception is copied here: System.TypeInitializationException was unhandled Message="The type initializer for 'MyCompany.SystemSoftware.SystemInfo.RuntimeInfo' threw an exception." Source="AndeDataViewer" TypeName="MyCompany.SystemSoftware.SystemInfo.RuntimeInfo" StackTrace: at AndeDataViewer.DbAccess..ctor() in C:\workspace\SystemSoftware\Other\AndeDataViewer\AndeDataViewer\DbAccess.cs:line 17 at AndeDataViewer.Window1.rbRawData_Checked(Object sender, RoutedEventArgs e) in C:\workspace\SystemSoftware\Other\AndeDataViewer\AndeDataViewer\Window1.xaml.cs:line 69 at System.Windows.RoutedEventHandlerInfo.InvokeHandler(Object target, RoutedEventArgs routedEventArgs) .... InnerException: System.NullReferenceException Message="Object reference not set to an instance of an object." Source="AndeDataViewer" StackTrace: at MyCompany.SystemSoftware.SystemInfo.RuntimeInfo..cctor() in C:\workspace\SystemSoftware\SystemSoftware\src\systeminfo\RuntimeInfo.cs:line 24 InnerException: I cannot understand this because it looks fine to me but why there is an exception? we cannot access static variable when a class is a linked class? A linked class should be the same as the local class I think. "Linked" here means when I add file I use "Add As Link".

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  • Does the compiler optimize the function parameters passed by value?

    - by Naveen
    Lets say I have a function where the parameter is passed by value instead of const-reference. Further, lets assume that only the value is used inside the function i.e. the function doesn't try to modify it. In that case will the compiler will be able to figure out that it can pass the value by const-reference (for performance reasons) and generate the code accordingly? Is there any compiler which does that?

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  • sql queries slower than expected

    - by neubert
    Before I show the query here are the relevant table definitions: CREATE TABLE phpbb_posts ( topic_id mediumint(8) UNSIGNED DEFAULT '0' NOT NULL, poster_id mediumint(8) UNSIGNED DEFAULT '0' NOT NULL, KEY topic_id (topic_id), KEY poster_id (poster_id), ); CREATE TABLE phpbb_topics ( topic_id mediumint(8) UNSIGNED NOT NULL auto_increment ); Here's the query I'm trying to do: SELECT p.topic_id, p.poster_id FROM phpbb_topics AS t LEFT JOIN phpbb_posts AS p ON p.topic_id = t.topic_id AND p.poster_id <> ... WHERE p.poster_id IS NULL; Basically, the query is an attempt to find all topics where the number of times someone other than the target user has posted in is zero. In other words, the topics where the only person who has posted is the target user. Problem is that query is taking a super long time. My general assumption when it comes to SQL is that JOINs of any are super fast and can be done in no time at all assuming all relevant columns are primary or foreign keys (which in this case they are). I tried out a few other queries: SELECT COUNT(1) FROM phpbb_topics AS t JOIN phpbb_posts AS p ON p.topic_id = t.topic_id; That returns 353340 pretty quickly. I then do these: SELECT COUNT(1) FROM phpbb_topics AS t JOIN phpbb_posts AS p ON p.topic_id = t.topic_id AND p.poster_id <> 77198; SELECT COUNT(1) FROM phpbb_topics AS t JOIN phpbb_posts AS p ON p.topic_id = t.topic_id WHERE p.poster_id <> 77198; And both of those take quite a while (between 15-30 seconds). If I change the < to a = it takes no time at all. Am I making some incorrect assumptions? Maybe my DB is just foobar'd?

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  • Creating an adjacency List for DFS

    - by user200081
    I'm having trouble creating a Depth First Search for my program. So far I have a class of edges and a class of regions. I want to store all the connected edges inside one node of my region. I can tell if something is connected by the getKey() function I have already implemented. If two edges have the same key, then they are connected. For the next region, I want to store another set of connected edges inside that region, etc etc. However, I am not fully understanding DFS and I'm having some trouble implementing it. I'm not sure when/where to call DFS again. Any help would be appreciated! class edge { private: int source, destination, length; int key; edge *next; public: getKey(){ return key; } } class region { edge *data; edge *next; region() { data = new edge(); next = NULL; } }; void runDFS(int i, edge **edge, int a) { region *head = new region(); aa[i]->visited == true;//mark the first vertex as true for(int v = 0; v < a; v++) { if(tem->edge[i].getKey() == tem->edge[v].getKey()) //if the edges of the vertex have the same root { if(head->data == NULL) { head->data = aa[i]; head->data->next == NULL; } //create an edge if(head->data) { head->data->next = aa[i]; head->data->next->next == NULL; }//if there is already a node connected to ti } if(aa[v]->visited == false) runDFS(v, edge, a); //call the DFS again } //for loop }

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  • How to make this JavaScript much faster?

    - by Ralph
    Still trying to answer this question, and I think I finally found a solution, but it runs too slow. var $div = $('<div>') .css({ 'border': '1px solid red', 'position': 'absolute', 'z-index': '65535' }) .appendTo('body'); $('body *').live('mousemove', function(e) { var topElement = null; $('body *').each(function() { if(this == $div[0]) return true; var $elem = $(this); var pos = $elem.offset(); var width = $elem.width(); var height = $elem.height(); if(e.pageX > pos.left && e.pageY > pos.top && e.pageX < (pos.left + width) && e.pageY < (pos.top + height)) { var zIndex = document.defaultView.getComputedStyle(this, null).getPropertyValue('z-index'); if(zIndex == 'auto') zIndex = $elem.parents().length; if(topElement == null || zIndex > topElement.zIndex) { topElement = { 'node': $elem, 'zIndex': zIndex }; } } }); if(topElement != null ) { var $elem = topElement.node; $div.offset($elem.offset()).width($elem.width()).height($elem.height()); } }); It basically loops through all the elements on the page and finds the top-most element beneath the cursor. Is there maybe some way I could use a quad-tree or something and segment the page so the loop runs faster?

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  • MVC Validator.TryValidateObject does not validate custom atrribute, validateAllProperties = true

    - by nealsu
    When calling Validator.TryValidateObject with validateAllProperties = true my custom validation attribute does not get triggered. The ValidationResult does not contain an entry for my erroneous property value. Below is the model, attribute and code used to test this. //Model public class Model { [AmountGreaterThanZero] public int? Amount { get; set; } } //Attribute public sealed class AmountGreaterThanZero: ValidationAttribute { private const string errorMessage = "Amount should be greater than zero."; public AmountGreaterThanZero() : base(errorMessage) { } public override string FormatErrorMessage(string name) { return errorMessage; } protected override ValidationResult IsValid(object value, ValidationContext validationContext) { if (value != null) { if ((int)value <= 0) { var message = FormatErrorMessage(validationContext.DisplayName); return new ValidationResult(message); } } return null; } } //Validation Code var container = new Container(); container.ModelList = new List<Model>() { new Model() { Amount = -5 } }; var validationContext = new ValidationContext(container, null, null); var validationResults = new List<ValidationResult>(); var modelIsValid = Validator.TryValidateObject(container, validationContext, validationResults, true); Note: That the validation works fine and ValidationResult returns with correct error message if I use the TryValidateProperty method.

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  • C++ game loop example

    - by David
    Can someone write up a source for a program that just has a "game loop", which just keeps looping until you press Esc, and the program shows a basic image. Heres the source I have right now but I have to use SDL_Delay(2000); to keep the program alive for 2 seconds, during which the program is frozen. #include "SDL.h" int main(int argc, char* args[]) { SDL_Surface* hello = NULL; SDL_Surface* screen = NULL; SDL_Init(SDL_INIT_EVERYTHING); screen = SDL_SetVideoMode(640, 480, 32, SDL_SWSURFACE); hello = SDL_LoadBMP("hello.bmp"); SDL_BlitSurface(hello, NULL, screen, NULL); SDL_Flip(screen); SDL_Delay(2000); SDL_FreeSurface(hello); SDL_Quit(); return 0; } I just want the program to be open until I press Esc. I know how the loop works, I just don't know if I implement inside the main() function, or outside of it. I've tried both, and both times it failed. If you could help me out that would be great :P

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