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  • Define a positive number to be isolated if none of the digits in its square are in its cube [closed]

    - by proglaxmi
    Define a positive number to be isolated if none of the digits in its square are in its cube. For example 163 is n isolated number because 69*69 = 26569 and 69*69*69 = 4330747 and the square does not contain any of the digits 0, 3, 4 and 7 which are the digits used in the cube. On the other hand 162 is not an isolated number because 162*162=26244 and 162*162*162 = 4251528 and the digits 2 and 4 which appear in the square are also in the cube. Write a function named isIsolated that returns 1 if its argument is an isolated number, it returns 0 if its not an isolated number and it returns -1 if it cannot determine whether it is isolated or not (see the note below). The function signature is: int isIsolated(long n) Note that the type of the input parameter is long. The maximum positive number that can be represented as a long is 63 bits long. This allows us to test numbers up to 2,097,151 because the cube of 2,097,151 can be represented as a long. However, the cube of 2,097,152 requires more than 63 bits to represent it and hence cannot be computed without extra effort. Therefore, your function should test if n is larger than 2,097,151 and return -1 if it is. If n is less than 1 your function should also return -1. Hint: n % 10 is the rightmost digit of n, n = n/10 shifts the digits of n one place to the right. The first 10 isolated numbers are N n*n n*n*n 2 4 8 3 9 27 8 64 512 9 81 729 14 196 2744 24 576 13824 28 784 21952 34 1156 39304 58 3364 195112 63 3969 250047

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  • Maximum length of a std::basic_string<_CharT> string

    - by themoondothshine
    Hey all, I was wondering how one can fix an upper limit for the length of a string (in C++) for a given platform. I scrutinized a lot of libraries, and most of them define it arbitrarily. The GNU C++ STL (the one with experimental C++0x features) has quite a definition: size_t npos = size_t(-1); /*!< The maximum value that can be stored in a variable of type size_t */ size_t _S_max_len = ((npos - sizeof(_Rep_base))/sizeof(_CharT) - 1) / 4; /*!< Where _CharT is a template parameter; _Rep_base is a structure which encapsulates the allocated memory */ Here's how I understand the formula: The size_t type must hold the count of units allocated to the string (where each unit is of type _CharT) Theoretically, the maximum value that a variable of type size_t can take on is the total number of units of 1 byte (ie, of type char) that may be allocated The previous value minus the overhead required to keep track of the allocated memory (_Rep_base) is therefore the maximum number of units in a string. Divide this value by sizeof(_CharT) as _CharT may require more than a byte Subtract 1 from the previous value to account for a terminating character Finally, that leave the division by 4. I have absolutely no idea why! I looked at a lot of places for an explanation, but couldn't find a satisfactory one anywhere (that's why I've been trying to make up something for it! Please correct me if I'm wrong!!).

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  • write a function using generic

    - by user296551
    hi,guy, i want write a function using c#, and it accept any type parameter,i want use generic list to do, but i can't finish, it's wrong, how to do it? perhaps there are other ways?? thinks! public class City { public int Id; public int? ParentId; public string CityName; } public class ProductCategory { public int Id; public int? ParentId; public string Category; public int Price; } public class Test { public void ReSortList<T>(IEnumerable<T> sources, ref IEnumerable<T> returns, int parentId) { //how to do like this: /* var parents = from source in sources where source.ParentId == parentId && source.ParentId.HasValue select source; foreach (T child in parents) { returns.Add(child); ReSortList(sources, ref returns, child.Id); } */ } public void Test() { IList<City> city = new List<City>(); city.Add(new City() { Id = 1, ParentId = 0, CityName = "China" }); city.Add(new City() { Id = 2, ParentId = null, CityName = "America" }); city.Add(new City() { Id = 3, ParentId = 1, CityName = "Guangdong" }); IList<City> results = new List<City>(); ReSortList<City>(city, ref results, 0); //error } }

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  • MySQLi Wrapper -- will this slow down performance?

    - by Kerry
    I found the following code on php.net. I'm trying to write a wrapper for the MySQLi library to make things incredibly simple. If this is going to slow down performance, I'll skip it and find another way, if this works, then I'll do that. I have a single query function, if someone passes in more than one variable, I assume the function has to be prepared. The function that I would use to pass in an array to mysqli_stmt_bind_param is call_user_func_array, I have a feeling that is going to slow things down. Am I right? <?php /* just explaining how to call mysqli_stmt_bind_param with a parameter array */ $sql_link = mysqli_connect('localhost', 'my_user', 'my_password', 'world'); $type = "isssi"; $param = array("5", "File Description", "File Title", "Original Name", time()); $sql = "INSERT INTO file_detail (file_id, file_description, file_title, file_original_name, file_upload_date) VALUES (?, ?, ?, ?, ?)"; $sql_stmt = mysqli_prepare ($sql_link, $sql); call_user_func_array('mysqli_stmt_bind_param', array_merge (array($sql_stmt, $type), $param); mysqli_stmt_execute($sql_stmt); ?>

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  • Value is zero after filter SQL in C#

    - by Chuki2
    I`m new in C#.. I have write function to filter department. And this function will return idDepartment. New problem is, department keep value "System.Windows.Forms.Label, Text : ADMIN ", that`s why i got zero. So how can i take "ADMIN" only and keep to department? Update : public partial class frmEditStaff : Form { private string connString; private string userId, department; //Department parameter coming from here private string conString = "Datasource"; public frmEditStaff(string strUserID, string strPosition) { InitializeComponent(); //Pass value from frmListStaff to userID text box tbStaffId.Text = strUserID.ToString(); userId = strUserID.ToString(); department = strPosition.ToString(); } This code below is working, don`t have any problem. public int lookUpDepart() { int idDepart=0; using (SqlConnection openCon = new SqlConnection(conString)) { string lookUpDepartmenId = "SELECT idDepartment FROM tbl_department WHERE department = '" + department + "';"; openCon.Open(); using (SqlCommand querylookUpDepartmenId = new SqlCommand(lookUpDepartmenId, openCon)) { SqlDataReader read = querylookUpDepartmenId.ExecuteReader(); while (read.Read()) { idDepart = int.Parse(read[0].ToString()); break; } } openCon.Close(); return idDepart; } } Thanks for help. Happy nice day!

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  • JQuery 1.3.1 doesn't find dynamically generated rows

    - by Bamelis Steve
    I have just installed in the ASP.NET MVC RC2 and with that also using the JQuery 1.3.1 library. Before I was using the 1.2.6 library. Our application works fine under that library. But now I have strange problem. We have a grid view that we build up with the result of an AJAX call. With the result returned we add new rows to a table through cloning a hidden row. The generated HTML from the JQuery is placing extra parameters to the tags. These are in the form of JQuery12345678="null". They all have the same name. In the head of the table there is a checkbox that selects/unselects all the rows of the table. This by iterating through the rows of the table. $("#selectAllCheckbox").click(function() { var checked = this.checked; $("#dgNewTasks tbody tr").find(':input[type="checkbox"]').each(function() { this.checked = checked; }); }); Now by using the new library the check box are no longer set. I have used IE Developer Tools to check the HTML. If I remove the JQuery12345678="null" parameter from my rows. It works fine. Could someone tell me what I have to do?

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  • Generic factory of generic containers

    - by Feuermurmel
    I have a generic abstract class Factory<T> with a method createBoxedInstance() which returns instances of T created by implementations of createInstance() wrapped in the generic container Box<T>. abstract class Factory<T> { abstract T createInstance(); public final Box<T> createBoxedInstance() { return new Box<T>(createInstance()); } public final class Box<T> { public final T content; public Box(T content) { this.content = content; } } } At some points I need a container of type Box<S> where S is an ancestor of T. Is it possible to make createBoxedInstance() itself generic so that it will return instances of Box<S> where S is chosen by the caller? Sadly, defining the function as follows does not work as a type parameter cannot be declared using the super keyword, only used. public final <S super T> Box<S> createBoxedInstance() { return new Box<S>(createInstance()); } The only alternative I see, is to make all places that need an instance of Box<S> accept Box<? extends S> which makes the container's content member assignable to S. Is there some way around this without re-boxing the instances of T into containers of type Box<S>? (I know I could just cast the Box<T> to a Box<S> but I would feel very, very guilty.)

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  • Server side method not getting called

    - by Rangel Fernandes
    From the below javascript code i am trying to call a serverside method, but serververside method is not getting called. I am using jquery, ajax <script type="text/javascript" src="JquryLib.js"></script> <script type="text/javascript" language="javascript"> function fnPopulateCities() { debugger; var State = $("#ddlState").val(); GetCities(State); return false; } function GetCities(StateId) { debugger; var v1 = 'StateId: ' + StateId; $.ajax( { type: "POST", url: 'DropDownList_Cascade.aspx/PopulateCities', data: '{' + v1 + '}', contentType: "application/json; charset=utf-8", dataType: "json", success: function (result) { if (result.status === "OK") { alert('Success!!'); } else { fnDisplayCities(result); } }, error: function (req, status, error) { alert("Sorry! Not able to retrieve cities"); } }); } </script> This is my serverside method which i need to call. private static ArrayList PopulateCities(int StateId) { //this code returns Cities ArrayList from database. } It is giving me the following error: 500 (Internal Server Error) I cannot figure out what is wrong. please help! Stack Trace: [ArgumentException: Unknown web method PopulateCities.Parameter name: methodName]

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  • Google Chrome && (cache || memory leaks).

    - by Alexey Ogarkov
    Hello All, I have a big problem with Google Chrome and its memory. My app is displaying to user several image charts and reloads them every 10s. In the interval i have code like that var image = new Image(); var src = 'myurl/image'+new Date().getTime(); image.onload = function() { document.getElementById('myimage').src = src; image.onload = image.onabort = image.onerror = null; } image.src = src; So i have no memory leaks in Firefox and IE. Here the response headers for images Server Apache-Coyote/1.1 Vary * Cache-Control no-store (// I try no-cache, must-revalidate and so on here) Content-Type image/png Content-Length 11131 Date Mon, 31 May 2010 14:00:28 GMT Vary * taken from here In about:cache page there is no my cached images. If i enable purge-memory-button for chrome (--purge-memory-button parameter) it`s not help. Images is in PNG24. So i think that the problem is not in cache. May be Google Chrome is not releasing memory for old images. Please help. Any suggestions. Thanks.

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  • FileInput Help/Advice

    - by user559142
    I have a fileinput class. It has a string parameter in the constructor to load the filename supplied. However it just exits if the file doesn't exist. I would like it to output a message if the file doesn't exist - but not sure how.... Here is the class: public class FileInput extends Input { /** * Construct <code>FileInput</code> object given a file name. */ public FileInput(final String fileName) { try { scanner = new Scanner(new FileInputStream(fileName)); } catch (FileNotFoundException e) { System.err.println("File " + fileName + " could not be found."); System.exit(1); } } /** * Construct <code>FileInput</code> object given a file name. */ public FileInput(final FileInputStream fileStream) { super(fileStream); } } And its implementation: private void loadFamilyTree() { out.print("Enter file name: "); String fileName = in.nextLine(); FileInput input = new FileInput(fileName); family.load(input); input.close(); }

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  • How to get java singleton object manager to return any type of object?

    - by Robert
    I'm writing an interactive fiction game in java from scratch. I'm currently storing all of my game object references in a hashmap in a singleton called ObjectManager. ObjectManager has a function called get which takes an integer ID and returns the appropriate reference. The problem is that it returns a BaseObject when I need to return subclasses of BaseObject with more functionality. So, what I've done so far is I've added a getEntity function which returns BaseEntity (which is a subclass of BaseObject). However, when I need the function to return to an object that is a subclass of BaseEntity that has added, required functionality, I will need to make another function. I know there is a better way, but I don't know what it is. I know very little of design patterns, and I'm not sure which one to use here. I tried passing 'class' as a parameter, but that didn't get me anywhere. public BaseObject get(int ID){ return (BaseObject)refMap.get(ID); } public BaseEntity getEntity(int ID){ return (BaseEntity)refMap.get(ID); } Thanks, java ninjas!

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  • Expressjs route param as variable in main app

    - by MoDFoX
    For my app I have two route set up, app.get('/', routes.index); app.get('/:name', routes.index); I would like it to be so that if I don't specify a param, say just go to appurl.com (localhost:3000), it would load a default user, but if I do specify a param(localhost:3000/user), use that as the variable "username" in the following function (placed after my routes). (function getUser(){ var body = '', username = 'WillsonSM', options = { host: 'ws.audioscrobbler.com', port: 80, path: '/2.0/?method=user.gettopartists&user=' + username + '&format=json&limit=20&api_key=APIKEYGOESHERE' }; require('http').request(options, function(res) { res.setEncoding('utf8'); res.on('data', function(chunk) { body += chunk; }); res.on('end', function() { body = JSON.parse(body); artists = body.topartists.artist; }); }).end(); })(); Along with this I have my route set up like so: exports.index = function(req, res){ res.render('index', { title: 'LasTube' }); username = req.params.name; console.log(username); }; unfortunately setting username there to req.params.name does not seem to be accessible from the main app function. My question is: How can I set expressjs/nodejs to use the parameter set via /name when available, and just use a default - in this example "WillsonSM" if not available. I've tried taking "username" out of the main app, and just leaving it in the function, but username becomes undefined, as it is inaccessible from the route, and the app will not run. I can spit out "username" via the routes console.log, so assigning it there is not an issue, but as I am new to expressjs, I am unaware of how I should go about doing this. I have tried all I can think of and find from looking around the internet. Also, if there is a better way of doing this, or I am doing something wrong, please let me know. If I've left out any information, just throw in a comment and I'll try to address it.

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  • Best method to cache objects in PHP?

    - by Martin Bean
    Hi, I'm currently developing a large site that handles user registrations. A social networking website for argument's sake. However, I've noticed a lag in page loads and deciphered that it is the creation of objects on pages that's slowing things down. For example, I have a Member object, that when instantiated with an ID passed as a construct parameter, it queries the database for that members' row in the members database table. Not bad, but this is created each time a page is loaded; and called more than once when say, calling an array of that particular members' friends, as a new Member object is created for each friend. So on a single page I can have upwards of seven of the same object, but containing different properties. What I'm wanting to do is to find a way to reduce the database load, and to allow persist objects between page loads. For example, the logged in user's object to be created on login (which I can do) but then stored somewhere for retrieval so I don't have to keep re-creating the object between page loads. What is the best solution for this? I've had a look at Memcache, but with it being a third-party module I can't have the web host install it on this occasion. What are my alternatives, and/or best practices in my case? Thanks in advance.

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  • [Scala] Using overloaded, typed methods on a collection

    - by stephanos
    I'm quite new to Scala and struggling with the following: I have database objects (type of BaseDoc) and value objects (type of BaseVO). Now there are multiple convert methods (all called 'convert') that take an instance of an object and convert it to the other type accordingly. For example: def convert(doc: ClickDoc): ClickVO = doc match { case null => null case _ => val result = new ClickVO result.x = doc.x result.y = doc.y result } Now I sometimes need to convert a list of objects. How would I do this - I tried: def convert[D <: MyBaseDoc, V <: BaseVO](docs: List[D]):List[V] = docs match { case List() => List() case xs => xs.map(doc => convert(doc)) } Which results in 'overloaded method value convert with alternatives ...'. I tried to add manifest information to it, but couldn't make it work. I couldn't even create one method for each because it'd say that they have the same parameter type after type erasure (List). Ideas welcome!

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  • WIN32 API question - Looking for answer asap

    - by Lalit_M
    We have developed a ASP.NET web application and has implemented a custom authentication solution using active directory as the credentials store. Our front end application uses a normal login form to capture the user name and password and leverages the Win32 LogonUser method to authenticate the user’s credentials. When we are calling the LogonUser method, we are using the LOGON32_LOGON_NETWORK as the logon type. The issue we have found is that user profile folders are being created under the C:\Users folder of the web server. The folder seems to be created when a new user who has never logged on before is logging in for the first time. As the number of new users logging into the application grows, disk space is shrinking due to the large number of new user folders getting created. Has anyone seen this behavior with the Win32 LogonUser method? Does anyone know how to disable this behavior? I have tried LOGON32_LOGON_BATCH but it was giving an error 1385 in authentication user. I need either of the solution 1) Is there any way to stop the folder generation. 2) What parameter I need to pass this to work? Thanks

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  • null reference problems with c#

    - by alex
    Hi: In one of my window form, I created an instance of a class to do some works in the background. I wanted to capture the debug messages in that class and displayed in the textbox in the window form. Here is what I did: class A //window form class { public void startBackGroundTask() { B backGroundTask = new B(this); } public void updateTextBox(string data) { if (data != null) { if (this.Textbox.InvokeRequired) { appendUIDelegate updateDelegate = new appendUIDelegate(updateUI); try { this.Invoke(updateDelegate, data); } catch (Exception e) { Console.WriteLine(e.Message); } } else { updateUI(data); } } } private void updateUI(string data) { if (this.Textbox.InvokeRequired) { this.Textbox.Invoke(new appendUIDelegate(this.updateUI), data); } else { //update the text box this.Textbox.AppendText(data); this.Textbox.AppendText(Environment.NewLine); } } private delegate void appendUIDelegate(string data); } class B // background task { A curUI; public b( A UI) { curUI = UI; } private void test() { //do some works here then log the debug message to UI. curUI.updateTextBox("message); } } I keep getting a null reference exception after this.Invoke(updateDelegate, data); is called. I know passing "this" as a parameter is strange. But I want to send the debug message to my window form. Please help. Thanks

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  • for loop vs std::for_each with lambda

    - by Andrey
    Let's consider a template function written in C++11 which iterates over a container. Please exclude from consideration the range loop syntax because it is not yet supported by the compiler I'm working with. template <typename Container> void DoSomething(const Container& i_container) { // Option #1 for (auto it = std::begin(i_container); it != std::end(i_container); ++it) { // do something with *it } // Option #2 std::for_each(std::begin(i_container), std::end(i_container), [] (typename Container::const_reference element) { // do something with element }); } What are pros/cons of for loop vs std::for_each in terms of: a) performance? (I don't expect any difference) b) readability and maintainability? Here I see many disadvantages of for_each. It wouldn't accept a c-style array while the loop would. The declaration of the lambda formal parameter is so verbose, not possible to use auto there. It is not possible to break out of for_each. In pre- C++11 days arguments against for were a need of specifying the type for the iterator (doesn't hold any more) and an easy possibility of mistyping the loop condition (I've never done such mistake in 10 years). As a conclusion, my thoughts about for_each contradict the common opinion. What am I missing here?

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  • '<=' operator is not working in sql server 2000

    - by Lalit
    Hello, Scenario is, database is in the maintenance phase. this database is not developed by ours developer. it is an existing database developed by the 'xyz' company in sql server 2000. This is real time database, where i am working now. I wanted to write the stored procedure which will retrieve me the records From date1 to date 2.so query is : Select * from MyTableName Where colDate>= '3-May-2010' and colDate<= '5-Oct-2010' and colName='xyzName' whereas my understanding I must get data including upper bound date as well as lower bound date. but somehow I am getting records from '3-May-2010' (which is fine but) to '10-Oct-2010' As i observe in table design , for ColDate, developer had used 'varchar' to store the date. i know this is wrong remedy by them. so in my stored procedure I have also used varchar parameters as @FromDate1 and @ToDate to get inputs for SP. this is giving me result which i have explained. i tried to take the parameter type as 'Datetime' but it is showing error while saving/altering the stored procedure that "@FromDate1 has invalid datatype", same for "@ToDate". situation is that, I can not change the table design at all. what i have to do here ? i know we can use user defined table in sql server 2008 , but there is version sql server 2000. which does not support the same. Please guide me for this scenario. **Edited** I am trying to write like this SP: CREATE PROCEDURE USP_Data (@Location varchar(100), @FromDate DATETIME, @ToDate DATETIME) AS SELECT * FROM dbo.TableName Where CAST(Dt AS DATETIME) >=@fromDate and CAST(Dt AS DATETIME)<=@ToDate and Location=@Location GO but getting Error: Arithmetic overflow error converting expression to data type datetime. in sql server 2000 What should be that ? is i am wrong some where ? also (202 row(s) affected) is changes every time in circular manner means first time sayin (122 row(s) affected) run again saying (80 row(s) affected) if again (202 row(s) affected) if again (122 row(s) affected) I can not understand what is going on ?

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  • Why does LogonUser place user profiles in c:\users of the server?

    - by Lalit_M
    We have developed a ASP.NET web application and has implemented a custom authentication solution using active directory as the credentials store. Our front end application uses a normal login form to capture the user name and password and leverages the Win32 LogonUser method to authenticate the user’s credentials. When we are calling the LogonUser method, we are using the LOGON32_LOGON_NETWORK as the logon type. The issue we have found is that user profile folders are being created under the C:\Users folder of the web server. The folder seems to be created when a new user who has never logged on before is logging in for the first time. As the number of new users logging into the application grows, disk space is shrinking due to the large number of new user folders getting created. Has anyone seen this behavior with the Win32 LogonUser method? Does anyone know how to disable this behavior? I have tried LOGON32_LOGON_BATCH but it was giving an error 1385 in authentication user. I need either of the solution 1) Is there any way to stop the folder generation. 2) What parameter I need to pass this to work? Thanks

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  • How to draw histogram in Processing

    - by theolc
    I have an arrayList and I would like to take the size of the ten arrayList elements and use the sizes to create a histogram. I understand processing coordinate system starts in the top left corner. My question is, how do I use the arrayList.size() values to start at 450 (based from a 500,500 window) and go upwards from there to create my histogram. The following is my function for the histogram, it is receiving as a parameter the arrayList called bins. void histogram(ArrayList[] bins) { //set window background(0,0,0); size(500,500); background(255,255,255); line(50,0,50,500); line(0,450,500,450); int i; for (i = 50; i <= 500; i+=45) { line(i,450,i,480); } for (i = 50; i <= 450; i+=45) { line(50,i,20,i); } } Thanks in adavance for any help and input!

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  • Twitter API PHP script error

    - by bardockyo
    I am having issues with my php script that I am using for gathering a users followers by accessing the twitter API. The script works fine for a user that has < 5000 followers but I tried adjusting the script using cursors to collect the complete set of users. Here is my script: <?php $cursor = -1; $file = fopen ('ids.csv', 'w+'); fwrite($file, "User id\n\r"); for ($i = 0; $i <= 1; $i++) { $xml = getFollowers($cursor); foreach ($xml->ids->id as $id) { fwrite($file, $id . ", "); fwrite($file, "\n"); } $cursor = $xml->next_cursor; } function getFollowers ($cursor) { $xmldata = 'https://api.twitter.com/1/followers/ids.xml?cursor='.$cursor.'&screen_name=microsoft'; $open = fopen($xmldata, 'r'); $content = stream_get_contents($open); fclose($open); $xml = simplexml_load_file($xmldata); return $xml; } ?> I am getting an error Warning: fopen("https://api.twitter.com/1/followers/ids.xml?cursor=-1&screen_name=microsoft") failed to open stream HTTP request failed bad request warning: stream_get_contents() expects parameter 1 to be resource, boolean given. Any ideas?

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  • Null pointer to struct which has zero size (empty)... It is a good practice?

    - by ProgramWriter
    Hi2All.. I have some null struct, for example: struct null_type { NullType& someNonVirtualMethod() { return *this; } }; And in some function i need to pass reference to this type. Reason: template <typename T1 = null_type, typename T2 = null_type, ... > class LooksLikeATupleButItsNotATuple { public: LooksLikeATupleButItsNotATuple(T1& ref1 = defParamHere, T2& ref2 = andHere..) : _ref1(ref1), _ref2(ref2), ... { } void someCompositeFunctionHere() { _ref1.someNonVirtualMethod(); _ref2.someNonVirtualMethod(); ... } private: T1& _ref1; T2& _ref2; ...; }; It is a good practice to use null reference as a default parameter?: *static_cast<NullType*>(0) It works on MSVC, but i have some doubts...

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  • int foo(type& bar); is a bad practice?

    - by Earlz
    Well, here we are. Yet another proposed practice that my C++ book has an opinion on. It says "a returning-value(non-void) function should not take reference types as a parameter." So basically if you were to implement a function like this: int read_file(int& into){ ... } and used the integer return value as some sort of error indicator (ignoring the fact that we have exceptions) then that function would be poorly written and it should actually be like void read_file(int& into, int& error){ } Now to me, the first one is much clearer and nice to use. If you want to ignore the error value, you do so with ease. But this book suggests the later. Note that this book does not say returning value functions are bad. It rather says that you should either only return a value or you should only use references. What are your thoughts on this? Is my book full of crap? (again)

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  • Template Syntax in C++

    - by Crystal
    I don't understand templates really and was trying to run a simple find the minimum for ints, doubles, chars. First question, why is template<typename T> sometimes used, and other times template<>? Second question, I do not know what I am doing wrong with the following code below: #include <iostream> template <typename T> T minimum(T arg1, T arg2) { return arg1 < arg2 ? arg1 : arg2; } template <typename T> // first I tried template <> instd of above, but wasn't sure the difference T minimum<const char *>(const char *arg1, const char *arg2) { return strcmp(arg1, arg2) ? arg2 : arg1; } int main() { std::cout << minimum<int>(4, 2) << '\n'; std::cout << minimum<double>(2.2, -56.7) << '\n'; std::cout << minimum(2.2, 2) << '\n'; } Compile Errors: error C2768: 'minimum' : illegal use of explicit template arguments error C2783: 'T minimum(const char *,const char *)' : could not deduce template argument for 'T' : see declaration of 'minimum' : error C2782: 'T minimum(T,T)' : template parameter 'T' is ambiguous : see declaration of 'minimum' Third, in getting familiar with separating .h and .cpp files, if I wanted this minimum() function to be a static function of my class, but it was the only function in that class, would I have to have a template class as well? I originally tried doing it that way instead of having it all in one file and I got some compile errors as well that I can't remember right now and was unsure how I would do that. Thanks!

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  • Assigning a 2D array (of pointers) to a variable in an object for access in C++?

    - by MrMormon
    I'm sorry if I didn't pick a descriptive or concise name. A lot of questions sound similar, but I haven't been able to find what I'm looking for. What I want to do is store a 2D array of pointers somewhere and assign a variable in some object to that array to be able to access it. Here's some example code that has the same compile error I'm getting with a bigger project. #include <iostream> using namespace std; struct X{ float * b[8][8]; X(){ *(b[1][5]) = 1; cout << *(b[1][5]) << endl; } void Set(float * c[8][8]){ b = c; cout << *(b[1][5]) << endl; } }; main(){ float * a[8][8]; *(a[1][5]) = 2; X obj; obj.Set(a); } What I want to happen in this code is that an X object starts with its own 2D array, whose value pointed to by b[1][5] should be printed as "1". Then the main method's 2D array, a, is passed to the object's Set() method and assigned to its array variable. The value pointed to by b[1][5] should then be printed as "2". However, I can't figure out what type the Set() parameter, c, should be. I get error: incompatible types in assignment of ‘float* (*)[8]’ to ‘float* [8][8]’ when I try to compile. As for why I want to do this, I'm trying to use an array of pointers to objects, not floats, but it's the same error.

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