Search Results

Search found 13388 results on 536 pages for 'certificate store'.

Page 459/536 | < Previous Page | 455 456 457 458 459 460 461 462 463 464 465 466  | Next Page >

  • segmentation fault in file operations in c

    - by mekasperasky
    #include<stdio.h> /* this is a lexer which recognizes constants , variables ,symbols, identifiers , functions , comments and also header files . It stores the lexemes in 3 different files . One file contains all the headers and the comments . Another file will contain all the variables , another will contain all the symbols. */ int main() { int i; char a,b[20],c; FILE *fp1; fp1=fopen("source.txt","r"); //the source file is opened in read only mode which will passed through the lexer //now lets remove all the white spaces and store the rest of the words in a file if(fp1==NULL) { perror("failed to open source.txt"); //return EXIT_FAILURE; } i=0; while(1) { a=fgetc(fp1); if(a !="") { b[i]=a; } else { fprintf(fp1, "%.20s\n", b); i=0; continue; } i=i+1; /*Switch(a) { case EOF :return eof; case '+':sym=sym+1; case '-':sym=sym+1; case '*':sym=sym+1; case '/':sym=sym+1; case '%':sym=sym+1; case ' */ } return 0; } how does this code end up in segmentation fault?

    Read the article

  • How to properly load HTML data from third party website using MVC+AJAX?

    - by Dmitry
    I'm building ASP.NET MVC2 website that lets users store and analyze data about goods found on various online trade sites. When user is filling a form to create or edit an item, he should have a button "Import data" that automatically fills some fields based on data from third party website. The question is: what should this button do under the hood? I see at least 2 possible solutions. First. Do the import on client side using AJAX+jQuery load method. I tried it in IE8 and received browser warning popup about insecure script actions. Of course, it is completely unacceptable. Second. Add method ImportData(string URL) to ItemController class. It is called via AJAX, does the import + data processing server-side and returns JSON-d result to client. I tried it and received server exception (503) Server unavailable when loading HTML data into XMLDocument. Also I have a feeling that dealing with not well-formed HTML (missing closing tags, etc.) will be a huge pain. Any ideas how to parse such HTML documents?

    Read the article

  • need to change TextBox.Text inside TextChanged, something forces form close

    - by Istrebitel
    I am making a TextBox behave like if it could store a null value. In order to do that, i have a variable NullMode that indicates wether the value is stored is Null, and in TextChanged i set that to false, and on specific user action i set it to true and Text to a value that indicates that there is null inside the textbox. Then, based on NullMode, textbox is drawn differently. Now, i have a semaphore-like approach in order to prevent event handle from firing when i dont need it. Here is how it looks: private void input_TextChanged(object sender, EventArgs e) { if (_preventTextBoxEvents) return; _preventTextBoxEvents = true; //if (NullMode) // Text = ""; NullMode = false; ValidateInput(); _preventTextBoxEvents = false; } Now, if i need to set a textbox text to something that should show while in nullmode, i just set _preventTextBoxEvents before i do to true and it works all right. BUT! I need to also remove the text when user tries to input something into the textbox! So i need to set Text to "". Problem is, if i uncomment that, form is closed after the event handler exits. I cannot prevent it (e.Cancel = true in FormClosing doesnt help!) and do not understand what can be causing it. There is no error message too (and i'm not doing try-catch). My logic, when i do Text="". OnTextChanged should fire, it should call my TextChanged and it will see _preventTextBoxEvents is true and exit, so there would be no stack overflow / infinite recursion. What is going on?

    Read the article

  • Editing a remote file on-the-fly with PHP

    - by user275074
    Hi, I have a requirement to edit a remote text file on-the-fly, the content of which currently stands at ~1Mb. I have tried a couple of approaches and both seem to be clunky or hog memory which I can't rely on. Thinking out logically what I'm trying to achieve is: FTP to a remote server. Download a copy of the file for backup purposes and store it somewhere locally. Open the remote file and add the necessary lines required. Remove lines from the remote file as per an array of un-required data generated from the local server. Is this possible? I've managed to code steps 1 and 2 but I'm having difficult with 3 and 4. The way I'm doing it now is to use fgets and return the whole string. Really, I don't want to do this as it involves manipulating and re-generating the whole string (and it's large) and then re-inserting it in between two markers in the remote file. Is there no way of manipulating the lines of text in the file on-the-fly?

    Read the article

  • curl cookie not creating on success

    - by Bin
    Hi I'm using cUrl(PHP) to post a login request and store response in cookie file. In my second request I'm passing cookie in header and post data to verify it. Issue is that cookie file is not created in first succesful request results in failure for second request. Please suggest me where I'm doing wrong. $cookiefile="/var/www/html/dimdim/cook.txt"; $url_log="http://my.dimdim.com/api/auth/login"; $p_log='request={"account":"bin6k","password":"password","group":"all"}'; $url_ver="http://my.dimdim.com/api/auth/verify"; $p_ver='request={"account":"bin6k","password":"password","group":"all"}'; $ch = curl_init(); //curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1); curl_setopt($ch, CURLOPT_COOKIEJAR, $cookiefile); curl_setopt($ch, CURLOPT_URL,$url_log); curl_setopt($ch, CURLOPT_POST, 1); curl_setopt($ch, CURLOPT_POSTFIELDS, $p_log); ob_start(); // prevent any output $retval=curl_exec ($ch); // execute the curl command ob_end_clean(); // stop preventing output curl_close ($ch); //print_r($retval); unset($ch); $ch = curl_init(); curl_setopt($ch, CURLOPT_RETURNTRANSFER,1); curl_setopt($ch, CURLOPT_COOKIEFILE, $cookiefile); curl_setopt($ch, CURLOPT_URL,$url_ver); curl_setopt($ch, CURLOPT_POST, 1); curl_setopt($ch, CURLOPT_POSTFIELDS, $p_log); $buf2 = curl_exec ($ch); curl_close ($ch); echo "".htmlentities($buf2);

    Read the article

  • how do i implement / build / create an 'in memory database' for my unit test

    - by Michel
    Hi all, i've started unit testing a while ago and as turned out i did more regression testing than unit testing because i also included my database layer thus going to the database verytime. So, implemented Unity to inject a fake database layer, but i of course want to store some data, and the main opinion was: "create an in-memory database" But what is that / how do i implement that? Main question is: i think i have to fake the database layer, but doesn't that make me create a 'simple database' myself or: how can i keep it simple and not rebuilding Sql Server just for my unit tests :) At the end of this question i'll give an explanation of the situation i got in on the project i just started on, and i was wondering if this was the way to go. Michel Current situation i've seen at this client is that testdata is contained in XML files, and there is a 'fake' database layer that connects all the xml files together. For the real database we're using the entity framework, and this works very simple. And now, in the 'fake' layer, i have top create all kind of classes to load, save, persist etc. the data. It sounds weird that there is so much work in the fake layer, and so little in the real layer. I hope this all makes sense :)

    Read the article

  • beforeClose not working in jGrowl?

    - by sparkymark75
    I have the following code which pulls json data from an ASP.NET page and displays these as notifications. The code will also take a note of what's been pulled through and store it in an array to prevent it being shown again in the same session. I'm now trying to implement functionality so that when the user closes a message, it's ID is recorded in a cookie to prevent it ever being shown again. To do this, I'm trying to write to the cookie when the beforeClose event fires. Everything else works fine apart from the saving to a cookie bit. Is there something wrong with my code that I'm missing? var alreadyGrowled = new Array(); var noteCookie = $.cookie("notificationsViewed"); if (noteCookie != null) { alreadyGrowled = noteCookie.split(","); } function growlCheckNew() { $.getJSON('getNotifications.aspx', function(data) { $(data).each(function(entryIndex, entry) { var newMessage = true; $(alreadyGrowled).each(function(index, msg_id) { if (entry['ID'] == msg_id) { newMessage = false; } }); if (newMessage == true) { $.jGrowl(entry['Message'], { sticky: true, header: entry['Title'], beforeClose: function(e, m) { $.cookie("notificationsViewed", entry['ID']); } }); } alreadyGrowled.push(entry['ID']); }); }); }

    Read the article

  • In a class with no virtual methods or superclass, is it safe to assume (address of first member vari

    - by Jeremy Friesner
    Hi all, I made a private API that assumes that the address of the first member-object in the class will be the same as the class's this-pointer... that way the member-object can trivially derive a pointer to the object that it is a member of, without having to store a pointer explicitly. Given that I am willing to make sure that the container class won't inherit from any superclass, won't have any virtual methods, and that the member-object that does this trick will be the first member object declared, will that assumption hold valid for any C++ compiler, or do I need to use the offsetof() operator (or similar) to guarantee correctness? To put it another way, the code below does what I expect under g++, but will it work everywhere? class MyContainer { public: MyContainer() {} ~MyContainer() {} // non-virtual dtor private: class MyContained { public: MyContained() {} ~MyContained() {} // Given that the only place Contained objects are declared is m_contained // (below), will this work as expected on any C++ compiler? MyContainer * GetPointerToMyContainer() { return reinterpret_cast<MyContainer *>(this); } }; MyContained m_contained; // MUST BE FIRST MEMBER ITEM DECLARED IN MyContainer int m_foo; // other member items may be declared after m_contained float m_bar; };

    Read the article

  • Rails runner command not saving to cache

    - by mark
    Hi I'm having a bit of a problem with a cron task generated by rails whenever plugin that should store remote data in the rails cache for display. What I have is this: schedule.rb set :path, '/var/www/apps/tuexplore/current' every 1.hour do runner "Weather.cache_remote", :environment => :production end calls this model class Weather def self.cache_remote Rails.cache.write('weather_data', Net::HTTP.get_response(URI.parse(WEATHER_URL)).body) end end Calling whenever returns this PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/home/deploy/.gem/ruby/1.8/bin 0 * * * * /var/www/apps/tuexplore/current/script/runner -e production "Weather.cache_remote" This doesn't work. Calling the weather model method from a controller works fine, but I need to schedule it hourly. The cron task causes a "Cache write: weather_data" entry to appear in the production log but data isn't stored nor output into the page. Additional information, I can log into production console and run Weather.cache_remote, then read the data from the rails cache. I'd be really appreciative if someone could point out the error of my ways. If further explanation is needed please ask. Thanks in advance for any pointers.

    Read the article

  • real time stock quotes, StreamReader performance optimization

    - by sean717
    I am working on a program that extracts real time quote for 900+ stocks from a website. I use HttpWebRequest to send HTTP request to the site and store the response to a stream and open a stream using the following code: HttpWebResponse response = (HttpWebResponse)request.GetResponse(); Stream stream = response.GetResponseStream (); StreamReader reader = new StreamReader( stream ) the size of the received HTML is large (5000+ lines), so it takes a long time to parse it and extract the price. For 900 files, It takes about 6 mins for parsing and extracting. Which my boss isn't happy with, he told me he'd want the whole process to be done in TWO mins. I've identified the part of the program that takes most of time to finish is parsing and extracting. I've tried to optimize the code to make it faster, the following is what I have now after some optimization: // skip lines at the top for(int i=0;i<1500;++i) reader.ReadLine(); // read the line that contains the price string theLine = reader.ReadLine(); // ... extract the price from the line now it takes about 4 mins to process all the files, there is still a significant gap to what my boss's expecting. So I am wondering, is there other way that I can further speed up the parsing and extracting and have everything done within 2 mins?

    Read the article

  • What's the recommended implementation for hashing OLE Variants?

    - by Barry Kelly
    OLE Variants, as used by older versions of Visual Basic and pervasively in COM Automation, can store lots of different types: basic types like integers and floats, more complicated types like strings and arrays, and all the way up to IDispatch implementations and pointers in the form of ByRef variants. Variants are also weakly typed: they convert the value to another type without warning depending on which operator you apply and what the current types are of the values passed to the operator. For example, comparing two variants, one containing the integer 1 and another containing the string "1", for equality will return True. So assuming that I'm working with variants at the underlying data level (e.g. VARIANT in C++ or TVarData in Delphi - i.e. the big union of different possible values), how should I hash variants consistently so that they obey the right rules? Rules: Variants that hash unequally should compare as unequal, both in sorting and direct equality Variants that compare as equal for both sorting and direct equality should hash as equal It's OK if I have to use different sorting and direct comparison rules in order to make the hashing fit. The way I'm currently working is I'm normalizing the variants to strings (if they fit), and treating them as strings, otherwise I'm working with the variant data as if it was an opaque blob, and hashing and comparing its raw bytes. That has some limitations, of course: numbers 1..10 sort as [1, 10, 2, ... 9] etc. This is mildly annoying, but it is consistent and it is very little work. However, I do wonder if there is an accepted practice for this problem.

    Read the article

  • Flexible forms and supporting database structure

    - by sunwukung
    I have been tasked with creating an application that allows administrators to alter the content of the user input form (i.e. add arbitrary fields) - the contents of which get stored in a database. Think Modx/Wordpress/Expression Engine template variables. The approach I've been looking at is implementing concrete tables where the specification is consistent (i.e. user profiles, user content etc) and some generic field data tables (i.e. text, boolean) to store non-specific values. Forms (and model fields) would be generated by first querying the tables and retrieving the relevant columns - although I've yet to think about how I would setup validation. I've taken a look at this problem, and it seems to be indicating an EAV type approach - which, from my brief research - looks like it could be a greater burden than the blessings it's flexibility would bring. I've read a couple of posts here, however, which suggest this is a dangerous route: How to design a generic database whose layout may change over time? Dynamic Database Schema I'd appreciate some advice on this matter if anyone has some to give regards SWK

    Read the article

  • MVVM: where is the best place to integrate an id counter, in ViewModel or Repository or... ?

    - by msfanboy
    Hello, I am using http://loungerepo.codeplex.com/ this library needs a unique id when I persist my entities to the repository. I decided for integer not Guid. The question is now where do I retrieve a new integer and how do I do it? This is my current approach in the SchoolclassAdministrationViewModel.cs: public SchoolclassAdministrationViewModel() { _schoolclassRepo = new SchoolclassRepository(); _pupilRepo = new PupilRepository(); _subjectRepo = new SubjectRepository(); _currentSchoolclass = new SchoolclassModel(); _currentPupil = new PupilModel(); _currentSubject = new SubjectModel(); ... } private void AddSchoolclass() { // get the last free id for a schoolclass entity _currentSchoolclass.SchoolclassID = _schoolclassRepo.LastID; // add the new schoolclass entity to the repository _schoolclassRepo.Add(SchoolclassModel.SchoolclassModelToSchoolclass(_currentSchoolclass)); // add the new schoolclass entity to the ObservableCollection bound to the View Schoolclasses.Add(_currentSchoolclass); // Create a new schoolclass entity and the bound UI controls content gets cleaned CurrentSchoolclass = new SchoolclassModel(); } public class SchoolclassRepository : IRepository<Schoolclass> { private int _lastID; public SchoolclassRepository() { _lastID = FetchLastId(); } public void Add(Schoolclass entity) { //repo.Store(entity); } private int FetchLastId() { return // repo.GetIDOfLastEntryAndDoInc++ } public int LastID { get { return _lastID; } } } Explanation: Every time the user switches to the SchoolclassAdministrationViewModel which is datatemplated with a UserControl the saVM Ctor is called and the schoolclass repository is created wherein the FetchLastId() is called and I am up to date with the last ID doing a inc++ on it to get the free one... Do you have any better ideas? What I do not like about my current apporach: -Having a private method in repositry class because a repositry is to fetch data only not "entity logic" like the counter - Having to access from the ViewModel a public property - located in the repository -, actually its not the ViewModel concern to get a entity id and assign it. Actually the ViewModel should ask for a schoolclass POCO and get a SchoolclassModel to bind to the UI. But then I have again to re-read the Schoolclass properties into the SchoolclassModel properties what I want to avoid.

    Read the article

  • Magento - Filter category resource collection by store_id

    - by Damodar Bashyal
    I am trying to pull category that belongs to current store only but it doesn't seem to work. Can anyone see any issue in my code? $categoryCollection = Mage::getResourceModel('catalog/category_collection') ->setStoreId(Mage::app()->getStore()->getId()) ->addFieldToFilter('include_in_menu', array('eq' => 1)) ->addFieldToFilter('is_active', array('eq' => 1)) ->addFieldToFilter('level', array('eq' => 2)) ->addAttributeToSelect(array('name','url_path','image','description')) ->setOrder('position', 'asc'); $categoryCollection->printLogQuery(true); That's getting data from store_id 0 as well, but i want from only store_id 2 SELECT `e`.*, IF(at_include_in_menu.value_id > 0, at_include_in_menu.value, at_include_in_menu_default.value) AS `include_in_menu`, IF(at_is_active.value_id > 0, at_is_active.value, at_is_active_default.value) AS `is_active` FROM `catalog_category_entity` AS `e` INNER JOIN `catalog_category_entity_int` AS `at_include_in_menu_default` ON (`at_include_in_menu_default`.`entity_id` = `e`.`entity_id`) AND (`at_include_in_menu_default`.`attribute_id` = '67') AND `at_include_in_menu_default`.`store_id` = 0 LEFT JOIN `catalog_category_entity_int` AS `at_include_in_menu` ON (`at_include_in_menu`.`entity_id` = `e`.`entity_id`) AND (`at_include_in_menu`.`attribute_id` = '67') AND (`at_include_in_menu`.`store_id` = 2) INNER JOIN `catalog_category_entity_int` AS `at_is_active_default` ON (`at_is_active_default`.`entity_id` = `e`.`entity_id`) AND (`at_is_active_default`.`attribute_id` = '42') AND `at_is_active_default`.`store_id` = 0 LEFT JOIN `catalog_category_entity_int` AS `at_is_active` ON (`at_is_active`.`entity_id` = `e`.`entity_id`) AND (`at_is_active`.`attribute_id` = '42') AND (`at_is_active`.`store_id` = 2) WHERE (`e`.`entity_type_id` = '3') AND (IF(at_include_in_menu.value_id > 0, at_include_in_menu.value, at_include_in_menu_default.value) = 1) AND (IF(at_is_active.value_id > 0, at_is_active.value, at_is_active_default.value) = 1) AND (`e`.`level` = 2)

    Read the article

  • C# algorithm for figuring out different possible combinations...

    - by ttomsen
    I have 10 boxes, each box can hold one item from a group/type of items, each 'group' type only fits in one of the 10 box types. The pool can have n number of items. The groups have completely distinct items. Each item has a price, i want an algorithm that will generate all the different possibilities, so i can figure out different price points. so a smaller picture of the problem BOX A - can have item 1,2,3,4 in it BOX B - can have item 6,7,8,9,10,11,12 BOX C - can have item 13,15,16,20,21 The items are stored in a db, they have a column which denotes which box they can go in. All box types are stored in an array, and I can put the items in a generic list. Anyone see a straightforward way to do this. I have tried doing 10 nested foreach's to see if i could find a simpler way. The nested loops will take MANY hours to run. the nested for each's basically pull all combinations, then calculate a rank for each combination, and store the top 10 ranked combination of items for output

    Read the article

  • array of structures, or structure of arrays?

    - by Jason S
    Hmmm. I have a table which is an array of structures I need to store in Java. The naive don't-worry-about-memory approach says do this: public class Record { final private int field1; final private int field2; final private long field3; /* constructor & accessors here */ } List<Record> records = new ArrayList<Record>(); If I end up using a large number ( 106 ) of records, where individual records are accessed occasionally, one at a time, how would I figure out how the preceding approach (an ArrayList) would compare with an optimized approach for storage costs: public class OptimizedRecordStore { final private int[] field1; final private int[] field2; final private long[] field3; Record getRecord(int i) { return new Record(field1[i],field2[i],field3[i]); } /* constructor and other accessors & methods */ } edit: assume the # of records is something that is changed infrequently or never I'm probably not going to use the OptimizedRecordStore approach, but I want to understand the storage cost issue so I can make that decision with confidence. obviously if I add/change the # of records in the OptimizedRecordStore approach above, I either have to replace the whole object with a new one, or remove the "final" keyword. kd304 brings up a good point that was in the back of my mind. In other situations similar to this, I need column access on the records, e.g. if field1 and field2 are "time" and "position", and it's important for me to get those values as an array for use with MATLAB, so I can graph/analyze them efficiently.

    Read the article

  • How to prepare data for display on a silverlight chart using WCF RIA Services + Entity Framework

    - by Banford
    I've used WCF RIA services with Entity Framework to build a simple application which can display and updates data about school courses. This was done by following the Microsoft tutorials. Now I would like to have a chart which shows a count for how many courses are on a key stage. Example: Key Stage 3 - 20 courses Key Stage 4 - 32 courses Key Stage 5 - 12 courses Displayed on any form of chart. I have no problem binding data to the chart in XAML. My problem is that I do not know how to correct way of getting the data into that format. The generated CRUD methods are basic. I have a few thoughts about possible ways, but don't know which is correct, they are: Create a View in SQL server and map this to a separate Entity in the Entity Data Model. Generating new CRUD methods for this automatically. Customise the read method in the existing DomainService using .Select() .Distinct() etc. Don't know this syntax very well labda expressions/LINQ??? what is it? Any good quickstarts on it? Create a new class to store only the data required and create a read method for it. Tried this but didn't know how to make it work without a matching entity in the entity model. Something I am not aware of. I'm very new to this and struggling with the concepts so if there are useful blogs or documentation I've missed feel free to point me towards them. But I'm unsure of the terminology to use in my searches at the moment.

    Read the article

  • Adding an Array inside an array in a PHP function

    - by bateman_ap
    I have created a function in PHP that calls a webservice and parses through the result, assinging values to variables and returning them all as an Array. This all works perfectly, however I have come across a need to have an "array within my array" I am assigning values as below: $productName = $product->Name; $productID = $product->ID; $productArray = array( 'productName' => "$productName", 'productID' => "$productID" ); return $productArray; However I now have a piece of data that comes back with multiple results so I need to have a additional array to store these, I am getting the values from the returned XML using a foreach loop, however I want to be able to add them to the array with a name so I can reference them in the returned data, this is where I have a problem... $bestForLists = $product->BestFors; foreach( $bestForLists as $bestForList ) { $productBestFors = $bestForList->BestFor; foreach( $productBestFors as $productBestFor ) { $productBestForName = $productBestFor->Name; $productBestForID = $productBestFor->ID; } } I tried creating an array for these using the below code: $bestForArray[] = (array( "productBestForID" => "$productBestForID", "productBestForName" => "$productBestForName" )); And then at the end merging these together: $productArray= array_merge($productArray,$bestForArray); If I print out the returned value I get: Array ( [productName] => Test Product [productID] => 14128 [0] => Array ( [productBestForID] => 56647 [productBestForName] => Lighting ) [1] => Array ( [productBestForID] => 56648 [productBestForName] => Sound ) ) I would like to give the internal Array a name so I can reference it in my code, or is there a better way of doing this, at the moment I am using the following in my PHP page to get values: $productName = $functionReturnedValues['productName']; I would like to use the following to access the array I could then loop through: $bestForArray = $functionReturnedValues['bestForArray']; Hope someone can help

    Read the article

  • Reading strings and integers from .txt file and printing output as strings only

    - by screename71
    Hello, I'm new to C++, and I'm trying to write a short C++ program that reads lines of text from a file, with each line containing one integer key and one alphanumeric string value (no embedded whitespace). The number of lines is not known in advance, (i.e., keep reading lines until end of file is reached). The program needs to use the 'std::map' data structure to store integers and strings read from input (and to associate integers with strings). The program then needs to output string values (but not integer values) to standard output, 1 per line, sorted by integer key values (smallest to largest). So, for example, suppose I have a text file called "data.txt" which contains the following three lines: 10 dog -50 horse 0 cat -12 zebra 14 walrus The output should then be: horse zebra cat dog walrus I've pasted below the progress I've made so far on my C++ program: #include <fstream> #include <iostream> #include <map> using namespace std; using std::map; int main () { string name; signed int value; ifstream myfile ("data.txt"); while (! myfile.eof() ) { getline(myfile,name,'\n'); myfile >> value >> name; cout << name << endl; } return 0; myfile.close(); } Unfortunately, this produces the following incorrect output: horse cat zebra walrus If anyone has any tips, hints, suggestions, etc. on changes and revisions I need to make to the program to get it to work as needed, can you please let me know? Thanks!

    Read the article

  • Compact data structure for storing a large set of integral values

    - by Odrade
    I'm working on an application that needs to pass around large sets of Int32 values. The sets are expected to contain ~1,000,000-50,000,000 items, where each item is a database key in the range 0-50,000,000. I expect distribution of ids in any given set to be effectively random over this range. The operations I need on the set are dirt simple: Add a new value Iterate over all of the values. There is a serious concern about the memory usage of these sets, so I'm looking for a data structure that can store the ids more efficiently than a simple List<int>or HashSet<int>. I've looked at BitArray, but that can be wasteful depending on how sparse the ids are. I've also considered a bitwise trie, but I'm unsure how to calculate the space efficiency of that solution for the expected data. A Bloom Filter would be great, if only I could tolerate the false negatives. I would appreciate any suggestions of data structures suitable for this purpose. I'm interested in both out-of-the-box and custom solutions. EDIT: To answer your questions: No, the items don't need to be sorted By "pass around" I mean both pass between methods and serialize and send over the wire. I clearly should have mentioned this. There could be a decent number of these sets in memory at once (~100).

    Read the article

  • Encapsulating user input of data for a class (C++)

    - by Dr. Monkey
    For an assignment I've made a simple C++ program that uses a superclass (Student) and two subclasses (CourseStudent and ResearchStudent) to store a list of students and print out their details, with different details shown for the two different types of students (using overriding of the display() method from Student). My question is about how the program collects input from the user of things like the student name, ID number, unit and fee information (for a course student) and research information (for research students): My implementation has the prompting for user input and the collecting of that input handled within the classes themselves. The reasoning behind this was that each class knows what kind of input it needs, so it makes sense to me to have it know how to ask for it (given an ostream through which to ask and an istream to collect the input from). My lecturer says that the prompting and input should all be handled in the main program, which seems to me somewhat messier, and would make it trickier to extend the program to handle different types of students. I am considering, as a compromise, to make a helper class that handles the prompting and collection of user input for each type of Student, which could then be called on by the main program. The advantage of this would be that the student classes don't have as much in them (so they're cleaner), but also they can be bundled with the helper classes if the input functionality is required. This also means more classes of Student could be added without having to make major changes to the main program, as long as helper classes are provided for these new classes. Also the helper class could be swapped for an alternative language version without having to make any changes to the class itself. What are the major advantages and disadvantages of the three different options for user input (fully encapsulated, helper class or in the main program)?

    Read the article

  • Database design: Calculating the Account Balance

    - by 001
    How do I design the database to calculate the account balance? 1) Currently I calculate the account balance from the transaction table In my transaction table I have "description" and "amount" etc.. I would then add up all "amount" values and that would work out the user's account balance. I showed this to my friend and he said that is not a good solution, when my database grows its going to slow down???? He said I should create separate table to store the calculated account balance. If did this, I will have to maintain two tables, and its risky, the account balance table could go out of sync. Any suggestion? EDIT: OPTION 2: should I add an extra column to my transaction tables "Balance". now I do not need to go through many rows of data to perform my calculation. Example John buys $100 credit, he debt $60, he then adds $200 credit. Amount $100, Balance $100. Amount -$60, Balance $40. Amount $200, Balance $240.

    Read the article

  • Decompress a GZipped response from the server (Socket)

    - by Lith
    Umm, ok, after sending some data to the server, noting this particular part: "Accept-Encoding: gzip,deflate\r\n" I am getting the following response: HTTP/1.1 200 OK Server: nginx Date: Fri, 09 Apr 2010 23:25:27 GMT Content-Type: text/html; charset=UTF-8 Transfer-Encoding: chunked Connection: keep-alive X-Powered-By: PHP/5.2.8 Expires: Mon, 26 Jul 1997 05:00:00 GMT Last-Modified: Fri, 09 Apr 2010 23:25:27 GMT Cache-Control: no-store, no-cache, must-revalidate Cache-Control: post-check=0, pre-check=0 Pragma: no-cache Content-Encoding: gzip Vary: Accept-Encoding 7aa ??U-?Rh?%?2?w??PM]??7?qZ?K?)???2?&??m???"q??/p9w?????x?[`tA!G???G?5z??????a>k????????Q ???N?? ('??f?,(??Y:5B???-?)?3x^0e:j?`,???**???F>G)?2????@???b??????A?k???Ar?n? But how do I decompress it? Note that I am using the Socket Class to do all the work. I know how to decompress it, but the problem here lies in the fact that I cannot separate the Packet from the GZipped data, psuedo-psuedocode (or whatever) on how I do it: Socket sends packet; Socket reads response from server, stores into a ByteArray; Create MemoryStream, use ByteArray; Create GZipStream, use Memorystream; now the problem occurs; I am getting the following Error: System.IO.InvalidDataException The magic number in GZip header is not correct. Make sure you are passing in a GZip stream. I hope the explanation is clear enough __.

    Read the article

  • Creating a global variable on the fly. [PHP ENCRYPTION]

    - by stormdrain
    Is there a way to dynamically create constant variables on the fly? The idea is that upon logging into the system, a user would be asked to upload a small text file that would be fread, and assigned to a var that would be accessible throughout the system. If this is possible, just to be clear, would this variable then only be accessible to that user and only while the session is alive? Security being the main concern here, would it be more practical to store the var in a session variable? The plan: Data in the db will be encrypted via mcrypt, and the key will be stored on USB thumbdrives. The user will insert the thumbdrive when going to access the system. Upon logging in, the app will prompt the user to upload the key. They will navigate to the thumbdrive and key. Via fopen and fread, the key will be assigned to a global var which will then allow access to encrypted data, and will be used to encrypt new info being entered to the db. When the user logs out, or session times out, the global var will become empty. Thanks!

    Read the article

  • pdf external streams in Max OS X Preview

    - by olpa
    According to the specification, a part of a PDF document can reside in an external file. An example for an image: 2 0 obj << /Type /XObject /Subtype /Image /Width 117 /Height 117 /BitsPerComponent 8 /Length 0 /ColorSpace /DeviceRGB /FFilter /DCTDecode /F (pinguine.jpg) >> stream endstream endobj I found that this functionality does work in Adobe Acrobat 5.0 for Windows (sample PDF with the image), also I managed to view this file in Adobe Acrobat Reader 8.1.3 for Mac OS X after I found the setting "Allow external content". Unfortunately, it seems that non-Adobe tools ignore the external stream feature. I hope I'm wrong, therefore ask the question: How to enable external streams in Mac OS X? (I think that all the system Mac OS X tools use the same library, therefore say "Mac OS X" instead of "Preview".) Or maybe there could be a programming hook to emulate external streams? My task is: store a big set of images (total ˜300Mb) outside of a small PDF (˜1Mb). At some moment, I want to filter PDF through a quartz filter and get a PDF with the images embedded. Any suggestions are welcome.

    Read the article

< Previous Page | 455 456 457 458 459 460 461 462 463 464 465 466  | Next Page >