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Time complexity to fill hash table (homework)?

- by Heathcliff

This is a homework question, but I think there's something missing from it. It asks: Provide a sequence of m keys to fill a hash table implemented with linear probing, such that the time to fill it is minimum. And then Provide another sequence of m keys, but such that the time fill it is maximum. Repeat these two questions if the hash table implements quadratic probing I can only assume that the hash table has size m, both because it's the only number given and because we have been using that letter to address a hash table size before when describing the load factor. But I can't think of any sequence to do the first without knowing the hash function that hashes the sequence into the table. If it is a bad hash function, such that, for instance, it hashes every entry to the same index, then both the minimum and maximum time to fill it will take O(n) time, regardless of what the sequence looks like. And in the average case, where I assume the hash function is OK, how am I suppossed to know how long it will take for that hash function to fill the table? Aren't these questions linked to the hash function stronger than they are to the sequence that is hashed? As for the second question, I can assume that, regardless of the hash function, a sequence of size m with the same key repeated m-times will provide the maximum time, because it will cause linear probing from the second entry on. I think that will take O(n) time. Is that correct? Thanks

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How can i bind parent's property to its child's property?

- by walkor

I have a GroupBox, which is defined like this <ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:local="clr-namespace:Groupbox" > <Style TargetType="local:GroupBox"> <Setter Property="BorderBrush" Value="DarkGray"/> <Setter Property="BorderThickness" Value="1"/> <Setter Property="Padding" Value="6"/> <Setter Property="Template"> <Setter.Value> <ControlTemplate TargetType="local:GroupBox"> <Grid Background="{TemplateBinding Background}"> <Grid.RowDefinitions> <RowDefinition Height="Auto"/> <RowDefinition Height="Auto"/> <RowDefinition Height="*"/> </Grid.RowDefinitions> <Border BorderThickness="{TemplateBinding BorderThickness}" Grid.Row="1" Grid.RowSpan="2" BorderBrush="{TemplateBinding BorderBrush}" CornerRadius="3"> <Border.Clip> <GeometryGroup FillRule="EvenOdd"> <RectangleGeometry x:Name="FullRect" Rect="0,0,300,200"/> <RectangleGeometry x:Name="HeaderRect" Rect="6,0,100,100"/> </GeometryGroup> </Border.Clip> </Border> <ContentPresenter Grid.Row="2" ContentTemplate="{TemplateBinding ContentTemplate}" Content="{TemplateBinding Content}" Margin="{TemplateBinding Padding}"/> <ContentControl x:Name="HeaderContainer" Margin="6,0,0,0" Grid.Row="0" Grid.RowSpan="2" HorizontalAlignment="Left"> <ContentPresenter Margin="3,0,3,0" ContentTemplate="{TemplateBinding HeaderTemplate}" Content="{TemplateBinding Header}"/> </ContentControl> </Grid> </ControlTemplate> </Setter.Value> </Setter> </Style> </ResourceDictionary> And i'm using this control like this <Controls:GroupBox x:Name="GroupBox"> <Controls:GroupBox.HeaderTemplate> <DataTemplate> <CheckBox "Header" x:Name="cbHeader"/> </DataTemplate> </Controls:GroupBox.HeaderTemplate> <Controls:GroupBox> So, well, my questions - how can i bind property IsEnabled of GroupBox to the Checkbox property IsChecked? Thanks in advance.

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Incorrect sizing of a JPanel in a JScrollPane In Java 1.5

- by Coder

Hi, I am making an image loading component which consists of a JPanel containing a JScrollPane, which in turn contains another JPanel. What this component does is allows images to be dropped on top of it, after which point the image is loaded and the inner most JPanel is set to the size of the image dropped. This in turn causes the scroll bars to show up and the user can scroll the image. This all works fine. The problem comes in when i try to auto-shrink the image to the maximum visible area in the outer JPanel. In this case i do a uniform scale of the image to be less than or equal to the width and height of the outer JPanel. What happens now is that both the horizontal and vertical scroll bars show up indicating the the inner JPanel is bigger than the visible area (which should not be the case). I verified that the image is scale to the proper dimensions(ie. the maximum width and height is respected). I also verified that if i decrease the maximum height by 3 pixels, then no scroll bars appear. What i believe the problem is, is that panel.getWidth() and panel.getHeight() don't actually return the visible area (maximum area) that sub components can take up. Ie. there is likely some more width and height taken up by the border around the JPanel or something like that. My question is, how do i get around this problem. Functionally all i want is to determine the maximum size a JPanel can be in a JScrollPane, then set the panel to that size and paint an image over top of it and be assured that the scroll bars of the scroll pane will not show up. Right now the scroll bars are set to AS_NEEDED. Thanks!

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How to make HTML layout whitespace-agnostic?

- by ssg

If you have consecutive inline-blocks white-space becomes significant. It adds some level of space between elements. What's the "correct" way of avoiding whitespace effect to HTML layout if you want those blocks to look stuck to each other? Example: <span>a</span> <span>b</span> This renders differently than: <span>a</span><span>b</span> because of the space inbetween. I want whitespace-effect to go away without compromising HTML source code layout. I want my HTML templates to stay clean and well-indented. I think these options are ugly: 1) Tweaking text-indent, margin, padding etc. (Because it would be dependent on font-size, default white-space width etc) 2) Putting everything on a single line, next to each other. 3) Zero font-size. That would require overriding font-size in blocks, which would otherwise be inherited. 4) Possible document-wide solutions. I want the solution to stay local for a certain block of HTML. Any ideas, any obvious points which I'm missing?

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Uploading a file fails under WordPress

- by Ash

I'm using WordPress and I'm following W3's guide for uploading a file: HTML code: <html> <body> <form action="upload_file.php" method="post" enctype="multipart/form-data"> <label for="file">Filename:</label> <input type="file" name="file" id="file" /> <br /> <input type="submit" name="submit" value="Submit" /> </form> </body> </html> PHP code (upload_file.php): <?php if ($_FILES["file"]["error"] > 0) { echo "Error: " . $_FILES["file"]["error"] . "<br />"; } else { echo "Upload: " . $_FILES["file"]["name"] . "<br />"; echo "Type: " . $_FILES["file"]["type"] . "<br />"; echo "Size: " . ($_FILES["file"]["size"] / 1024) . " Kb<br />"; echo "Stored in: " . $_FILES["file"]["tmp_name"]; } ?> The HTML code is pasted in a PHP page template and the PHP file under the WP installation directory under www. The problem is when I submit the file I get Error: 1. If I remark the "if" part of the PHP code and leave the "else" part I get: Upload: IMG_4258.JPG Type: Size: 0 Kb Stored in: So at least I know the PHP code is running. But what's causing it to fail? Is there a problem with the code or is WordPress meddling with the process?

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extract data from an array without using loop in R

- by Manolo

I have a vector v with row positions: v<-c(10,3,100,50,...) with those positions I want to extract elements of a matrix, having a column fixed, for example lets suppose my column number is 2, so I am doing: data<-c() data<-c(matrix[[v]][[2]]) matrix has the data in the following format: [[34]] [1] "200_s_at" "4853" "1910" "3554" "2658" So for example, I want to extract from the row 342 the value 1910 only, column 2, and do the same with the next rows but I got an error when I want to do that, is it possible to do it directly? or should I have a loop that read one by one the positions in v and fill the data vector like: #algorithm for i<-1 to length(v) pos<-v[i] data[[i]]<-c(matriz[[pos]][[2]]) next i Thanks

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I want to get the value from one class (SearchTableViewController.m) to another class (HistoryTableV

- by ahmet732

#import <UIKit/UIKit.h> @class SearchDetailViewController; @interface SearchTableViewController : UITableViewController <UISearchBarDelegate, UITableViewDelegate, UITableViewDataSource>{ IBOutlet UITableView *myTableView; NSMutableArray *tableData;//will be storing data that will be displayed in table. //Search array den buna aktarma yapcaz ilerde görceksin. NSMutableArray *searchedData;//will be storing data matching with the search string UISearchBar *sBar;//search bar NSMutableArray *searchArray; // It holds the medicines that are shown in tableview SearchDetailViewController * searchDetailViewController; NSMutableArray *deneme; } @property(nonatomic,retain)UISearchBar *sBar; @property(nonatomic,retain)IBOutlet UITableView *myTableView; @property(nonatomic,retain)NSMutableArray *tableData; @property(nonatomic,retain)NSMutableArray *searchedData; @property (nonatomic, retain) NSMutableArray *searchArray; @property (nonatomic, retain) SearchDetailViewController *searchDetailViewController; @property (nonatomic, copy) NSMutableArray *deneme; @end SearchTableViewController.m - (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath { // Navigation logic may go here. Create and push another view controller. // AnotherViewController *anotherViewController = [[AnotherViewController alloc] initWithNibName:@"AnotherView" bundle:nil]; // [self.navigationController pushViewController:anotherViewController]; // [anotherViewController release]; **deneme= [[NSMutableArray alloc]init]; deneme=[tableData objectAtIndex:indexPath.row];** ****NSLog(@"my row = %@", deneme);**// I holded one of the selected cells here** HistoryTableViewController.m - (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath { // Navigation logic may go here. Create and push another view controller. // AnotherViewController *anotherViewController = [[AnotherViewController alloc] initWithNibName:@"AnotherView" bundle:nil]; // [self.navigationController pushViewController:anotherViewController]; // [anotherViewController release]; **SearchTableViewController *obj= [[SearchTableViewController alloc]init];** **NSLog(@"my 2nd row= %@", [obj deneme]); //it prints nil** } My project is TabBar. There are two buttons on it- Search and History. I want to display selected items in a table in History tab. But i can not bring the selected item from SearchTableViewController.m to the class (HistoryTableViewController.m) The problem is : I can hold one of the selected items in an array (named deneme)from table in SearchTableViewController.m but i can not take it to HistoryTableViewController.m. It prints nil in console screen.... If I can make it visible in History class, I display those selected items on table. Please help me !!!

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Getting specific values with regex [JAVA, ANDROID]

- by David

I need to knowingly isolate each row of the vcard and get its value. For instance, I want to get "5555" from X-CUSTOMFIELD. So far, my thoughts are: "X-CUSTOMFIELD;\d+" I have been looking at some tutorials and I am a little confused with what function to use? What would my regex above return? Would it give me the whole line or just the numerical part (5555)? I was thinking I i get the whole row, I can use substring to get the digits? BEGIN:VCARD VERSION:2.1 N:Last;First; FN:First Last TEL;HOME;VOICE:111111 TEL;MOBILE;VOICE:222222 X-CUSTOMFIELD;5555 END:VCARD

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How to use for loop in xslt

- by Pramodh

Dear all, How to use for loop in xslt to get value iteratively from a xml file and to dispaly it in table fromat for example: the xml file is like <order> <item name ="a"/> <item name ="b"/> <item name ="c"/> <item name ="d"/> <item name ="e"/> <item name ="f"/> <item name ="g"/> </order> and the output should be a b c d e f g the loop shold count the item and if it is divisble by 4 it should close the current row and add a new row and so on.. please help me to do this Thanks in advance

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Turning A Stacked List into workable data

- by BoSox

In Excel I have a list of names that in the cell appear stacked, and I want each name in its own column. I was thinking Python may be a good way to do this? Example: Joe Smith John Hawk Mike Green Lauren Smith One cell will look exactly like that, with each name on its line within the cell but all of the names contained in the cell. I have 50 cells each with 1-20 stacked names and I want to put each name in its own cell on a given row. So, in my example all of those names would occupy the same row but each would have their own column. Any ideas?

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What is the preferred sql server column definition to use for a LINQ to SQL Version property?

- by Mike Two

We are using the IsVersion property on the ColumnAttribute on a property in a LINQ to SQL class for optimistic concurrency checks. What should the column definition be in the database? Currently we are using version_number int NOT NULL IDENTITY (1, 1) Do we need Identity? Can we get LINQ to SQL to update the version number for us? The only issue with Identity is that every row has a different number. We'd like to see the number increment by 1 when the row is updated.

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Potential problem with C standard malloc'ing chars.

- by paxdiablo

When answering a comment to another answer of mine here, I found what I think may be a hole in the C standard (c1x, I haven't checked the earlier ones and yes, I know it's incredibly unlikely that I alone among all the planet's inhabitants have found a bug in the standard). Information follows: Section 6.5.3.4 ("The sizeof operator") para 2 states "The sizeof operator yields the size (in bytes) of its operand". Para 3 of that section states: "When applied to an operand that has type char, unsigned char, or signed char, (or a qualified version thereof) the result is 1". Section 7.20.3.3 describes void *malloc(size_t sz) but all it says is "The malloc function allocates space for an object whose size is specified by size and whose value is indeterminate". It makes no mention at all what units are used for the argument. Annex E startes the 8 is the minimum value for CHAR_BIT so chars can be more than one byte in length. My question is simply this: In an environment where a char is 16 bits wide, will malloc(10 * sizeof(char)) allocate 10 chars (20 bytes) or 10 bytes? Point 1 above seems to indicate the former, point 2 indicates the latter. Anyone with more C-standard-fu than me have an answer for this?

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MSSQL 2005: Update rows in a specified order (like ORDER BY)?

- by JMTyler

I want to update rows of a table in a specific order, like one would expect if including an ORDER BY clause, but MS SQL does not support the ORDER BY clause in UPDATE queries. I have checked out this question which supplied a nice solution, but my query is a bit more complicated than the one specified there. UPDATE TableA AS Parent SET Parent.ColA = Parent.ColA + (SELECT TOP 1 Child.ColA FROM TableA AS Child WHERE Child.ParentColB = Parent.ColB ORDER BY Child.Priority) ORDER BY Parent.Depth DESC; So, what I'm hoping that you'll notice is that a single table (TableA) contains a hierarchy of rows, wherein one row can be the parent or child of any other row. The rows need to be updated in order from the deepest child up to the root parent. This is because TableA.ColA must contain an up-to-date concatenation of its own current value with the values of its children (I realize this query only concats with one child, but that is for the sake of simplicity - the purpose of the example in this question does not necessitate any more verbosity), therefore the query must update from the bottom up. The solution suggested in the question I noted above is as follows: UPDATE messages SET status=10 WHERE ID in (SELECT TOP (10) Id FROM Table WHERE status=0 ORDER BY priority DESC ); The reason that I don't think I can use this solution is because I am referencing column values from the parent table inside my subquery (see WHERE Child.ParentColB = Parent.ColB), and I don't think two sibling subqueries would have access to each others' data. So far I have only determined one way to merge that suggested solution with my current problem, and I don't think it works. UPDATE TableA AS Parent SET Parent.ColA = Parent.ColA + (SELECT TOP 1 Child.ColA FROM TableA AS Child WHERE Child.ParentColB = Parent.ColB ORDER BY Child.Priority) WHERE Parent.Id IN (SELECT Id FROM TableA ORDER BY Parent.Depth DESC); The WHERE..IN subquery will not actually return a subset of the rows, it will just return the full list of IDs in the order that I want. However (I don't know for sure - please tell me if I'm wrong) I think that the WHERE..IN clause will not care about the order of IDs within the parentheses - it will just check the ID of the row it currently wants to update to see if it's in that list (which, they all are) in whatever order it is already trying to update... Which would just be a total waste of cycles, because it wouldn't change anything. So, in conclusion, I have looked around and can't seem to figure out a way to update in a specified order (and included the reason I need to update in that order, because I am sure I would otherwise get the ever-so-useful "why?" answers) and I am now hitting up Stack Overflow to see if any of you gurus out there who know more about SQL than I do (which isn't saying much) know of an efficient way to do this. It's particularly important that I only use a single query to complete this action. A long question, but I wanted to cover my bases and give you guys as much info to feed off of as possible. :) Any thoughts?

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Mysql Date formats and url query

- by jasmine

I want to make a url query with date. I have confused a little : There is a mysql table: calDate : varchar The query : $sql="select * from calTbl"; $result = mysql_query($sql); while ($row = mysql_fetch_array($result)) { $n = str_replace("/", "",$row['calDate']); echo '<a href="index.php?p='.$n.'">'.$n.'</a>'; } I want to see related event from query. Can I set apart month, day and year from this? Or what is the correct table design here? Thanks in advance

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Doing a generic <sql:query> in Grails

- by melling

This is a generic way to select data from a table and show the results in an HTML table using JSP taglibs. What is the generic way to do this in Grails? That is, take a few lines of SQL and generate an HTML table from scratch in Grails, including the column names as headers. <sql:query var="results" dataSource="${dsource}" select * from foo </sql:query (# of rows: ${results.rowCount}) <table border="1" <!-- column headers -- <tr bgcolor=cyan <c:forEach var="columnName" items="${results.columnNames}" <th<c:out value="${columnName}"/</th </c:forEach </tr <!-- column data -- <c:forEach var="row" items="${results.rowsByIndex}" <tr <c:forEach var="column" items="${row}" <td<c:out value="${column}"/</td </c:forEach </tr </c:forEach </table The solution to this was answered in another StackOverFlow question. http://stackoverflow.com/questions/425294/sql-database-views-in-grails IF SOMEONE WRITES A GOOD ANSWER, I'LL ACCEPT IT. I would like a 100% acceptance on all of my questions.

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Business Objects Web Intelligence-style reporting in a Winform app. Is this possible?

- by George

I have a WinForm app that displays results in a Gridview control. If a user right mouse clicks on a row, he can then, from a popup menu, select a command to perform on the row much like windows File Explorer. But now I want to be able to give the user the ability to construct a filter so that he can control which rows are displayed in the grid w/o effecting the functionality of the application. I would also like the user to be able to select the columns/fields that he sees in the grid. For the basis of this question, let's assume that the data displayed in grid comes from a single table. business Objects' Web Intelligence and Desktop Intelligence applications give me very flexible and powerful reporting capabilities, but I want to integrate this capability into my WinForm application. Does Business Objects, or maybe Crystal Reports provide this sort of functionality? I can construct my own query builder but I'd rather not reinvent sliced bread.

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Packet fragmentation when sending data via SSLStream

- by Ive

When using an SSLStream to send a 'large' chunk of data (1 meg) to a (already authenticated) client, the packet fragmentation / dissasembly I'm seeing is FAR greater than when using a normal NetworkStream. Using an async read on the client (i.e. BeginRead()), the ReadCallback is repeatedly called with exactly the same size chunk of data up until the final packet (the remainder of the data). With the data I'm sending (it's a zip file), the segments happen to be 16363 bytes long. Note: My receive buffer is much bigger than this and changing it's size has no effect I understand that SSL encrypts data in chunks no bigger than 18Kb, but since SSL sits on top of TCP, I wouldn't think that the number of SSL chunks would have any relevance to the TCP packet fragmentation? Essentially, the data is taking about 20 times longer to be fully read by the client than with a standard NetworkStream (both on localhost!) What am I missing? EDIT: I'm beginning to suspect that the receive (or send) buffer size of an SSLStream is limited. Even if I use synchronous reads (i.e. SSLStream.Read()), no more data ever becomes available, regardless of how long I wait before attempting to read. This would be the same behavior as if I were to limit the receive buffer to 16363 bytes. Setting the Underlying NetworkStream's SendBufferSize (on the server), and ReceiveBufferSize (on the client) has no effect.

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disabling dropdownlist inside a gridview based on value selected on another dropdownlist inside the gridview from javascript or jquery

- by Joy

what i m trying is i hav two dropdownlists inside the gridview... namely say ddonsiteoffsite and ddhours... now what i want is if the selectedtext of ddonsiteoffsite is "onsite" the ddhours should b disabled... i tried the code snippet but ... its not disabling the ddhours... can someone help me please.. <asp:TemplateColumn HeaderText=" OnSite/OffSite" > <ItemTemplate> <asp:DropDownList ID="ddOnsiteOffside" runat="server" onchange="ToggleOnOff(this)"><asp:ListItem Text = "Offsite" Value="Offsite"></asp:ListItem> <asp:ListItem Text = "Onsite" Value="Onsite"></asp:ListItem> </asp:DropDownList> </ItemTemplate> </asp:TemplateColumn> <asp:TemplateColumn> <ItemTemplate> <asp:DropDownList ID="ddhours" runat="server"> <asp:ListItem Text = "1" Value="1" ></asp:ListItem> <asp:ListItem Text = "2" Value="2" ></asp:ListItem> <asp:ListItem Text = "3" Value="3" ></asp:ListItem> <asp:ListItem Text = "4" Value="4" ></asp:ListItem> <asp:ListItem Text = "5" Value="5" ></asp:ListItem> <asp:ListItem Text = "6" Value="6" ></asp:ListItem> <asp:ListItem Text = "7" Value="7" ></asp:ListItem> <asp:ListItem Text = "8" Value="8" ></asp:ListItem> <asp:ListItem Text = "9" Value="9" ></asp:ListItem> </asp:DropDownList> </ItemTemplate> </asp:TemplateColumn> and the corresponding javascript i am using is : enter code here function ToggleOnOff(ddonoff) { var row = chk.parentNode.parentNode; if(ddonoff.value=="Onsite") { row.getElementsByTagName("ddhours")[0].disabled = true; } else row.getElementsByTagName("ddhours")[0].disabled = false; } can someone help to achieve this ?? using javascript or jquery ? i m not understanding where i went wrong ...

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Performance on joins in linq

- by swapna

HI , I am going to rewrite a store procedure in LINQ. What this sp is doing is joining 12 tables and get the data and insert it into another table. it has 7 left outer joins and 4 inner joins.And returns one row of data. Now question. 1)What is the best way to achieve this joins in linq. 2) do you think this affect performance (its only retrieving one row of data at a given point of time) Please advice. Thanks SNA.

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bytea type & nulls, Postgres

- by Thanatos

I'm using a bytea type in PostgreSQL, which, to my understanding, contains just a series of bytes. However, I can't get it to play well with nulls. For example: =# select length(E'aa\x00aa'::bytea); length -------- 2 (1 row) I was expecting 5. Also: =# select md5(E'aa\x00aa'::bytea); md5 ---------------------------------- 4124bc0a9335c27f086f24ba207a4912 (1 row) That's the MD5 of "aa", not "aa\x00aa". Clearly, I'm Doing It Wrong, but I don't know what I'm doing wrong. I'm also on an older version of Postgres (8.1.11) for reasons outside of my control. (I'll see if this behaves the same on the latest Postgres as soon as I get home...)

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UITableViewCell Problem....

- by balu

Hi friends... i am creating a Custom reusable UITableViewCell with Three labels and one imageView,and i am removing them in cell's dealloc method... all is working fine but the problem is the text in cell getting Dark while selected... it and it is kind of overlapping on each other help me to avoid that problem... - (id)initWithStyle:(UITableViewCellStyle)style reuseIdentifier:(NSString *)reuseIdentifier { if (self = [super initWithStyle:style reuseIdentifier:reuseIdentifier]) { NSLog(@"Address for cel called"); NameLbl = [[UILabel alloc] initWithFrame:CGRectMake(5,5,140,20)]; [self.contentView addSubview:NameLbl]; NameLbl.font =[UIFont fontWithName:@"Times New Roman" size:15]; NameLbl.font = [UIFont boldSystemFontOfSize:15]; NameLbl.opaque=YES; NameLbl.tag = 1001; AddressLbl = [[UILabel alloc] initWithFrame:CGRectMake(5,25,140,20)]; [self.contentView addSubview:AddressLbl]; AddressLbl.font =[UIFont fontWithName:@"Times New Roman" size:15]; AddressLbl.opaque=YES; AddressLbl.tag = 1002; CityStateZipLbl = [[UILabel alloc] initWithFrame:CGRectMake(5,50,150,20)]; [self.contentView addSubview:CityStateZipLbl]; CityStateZipLbl.opaque=YES; CityStateZipLbl.tag = 1003; CityStateZipLbl.font =[UIFont fontWithName:@"Times New Roman" size:15]; } return self; } - (void)dealloc { [CityStateZipLbl release]; [NameLbl release]; [AddressLbl release]; [super dealloc]; }

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What is the fastest way for reading huge files in Delphi?

- by dummzeuch

My program needs to read chunks from a huge binary file with random access. I have got a list of offsets and lengths which may have several thousand entries. The user selects an entry and the program seeks to the offset and reads length bytes. The program internally uses a TMemoryStream to store and process the chunks read from the file. Reading the data is done via a TFileStream like this: FileStream.Position := Offset; MemoryStream.CopyFrom(FileStream, Size); This works fine but unfortunately it becomes increasingly slower as the files get larger. The file size starts at a few megabytes but frequently reaches several tens of gigabytes. The chunks read are around 100 kbytes in size. The file's content is only read by my program. It is the only program accessing the file at the time. Also the files are stored locally so this is not a network issue. I am using Delphi 2007 on a Windows XP box. What can I do to speed up this file access?

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On C++ global operator new: why it can be replaced

- by Jimmy

I wrote a small program in VS2005 to test whether C++ global operator new can be overloaded. It can. #include "stdafx.h" #include "iostream" #include "iomanip" #include "string" #include "new" using namespace std; class C { public: C() { cout<<"CTOR"<<endl; } }; void * operator new(size_t size) { cout<<"my overload of global plain old new"<<endl; // try to allocate size bytes void *p = malloc(size); return (p); } int main() { C* pc1 = new C; cin.get(); return 0; } In the above, my definition of operator new is called. If I remove that function from the code, then operator new in C:\Program Files (x86)\Microsoft Visual Studio 8\VC\crt\src\new.cpp gets called. All is good. However, in my opinion, my implementations of operator new does NOT overload the new in new.cpp, it CONFLICTS with it and violates the one-definition rule. Why doesn't the compiler complain about it? Or does the standard say since operator new is so special, one-definition rule does not apply here? Thanks.

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Would making plain int 64-bit break a lot of reasonable code?

- by R..

Until recently, I'd considered the decision by most systems implementors/vendors to keep plain int 32-bit even on 64-bit machines a sort of expedient wart. With modern C99 fixed-size types (int32_t and uint32_t, etc.) the need for there to be a standard integer type of each size 8, 16, 32, and 64 mostly disappears, and it seems like int could just as well be made 64-bit. However, the biggest real consequence of the size of plain int in C comes from the fact that C essentially does not have arithmetic on smaller-than-int types. In particular, if int is larger than 32-bit, the result of any arithmetic on uint32_t values has type signed int, which is rather unsettling. Is this a good reason to keep int permanently fixed at 32-bit on real-world implementations? I'm leaning towards saying yes. It seems to me like there could be a huge class of uses of uint32_t which break when int is larger than 32 bits. Even applying the unary minus or bitwise complement operator becomes dangerous unless you cast back to uint32_t. Of course the same issues apply to uint16_t and uint8_t on current implementations, but everyone seems to be aware of and used to treating them as "smaller-than-int" types.

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SQL Server 2008 GUID column is all 0's

- by Andy Evans

I'm hoping this is a simple goof I did on my end ... I have a table in my database set up like so: column name: widget_guid data type: uniqueidentifier allow nulls: false default value: newid() identity: false row guid: true When records are created (via LINQ to SQL) that the values in this field are formatted as a GUID but contain all 0's My assumption was that when a new record was created, that a guid would be autogenerated for that column, much like an auto-incrementing row id. Is this not true? Any help would be greatly appreciated. Thanks.

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