duplicates

How do I prevent duplicate entries into a list, and then ideally, sort that list? What I'm doing, is when information at one level is missing, taking the information from a level below it, to building the missing list, in the level above. Currently, I have XML similar to this: <c03 id="ref6488" level="file"> <did> <unittitle>Clinic Building</unittitle> <unitdate era="ce" calendar="gregorian">1947</unitdate> </did> <c04 id="ref34582" level="file"> <did> <container label="Box" type="Box">156</container> <container label="Folder" type="Folder">3</container> </did> </c04> <c04 id="ref6540" level=

I have been making a login/register system and I am drawing close to finishing my register portion of code. The only problem I am running into is how to make it so that users cannot register with duplicated usernames. I want it to work so that my database wont accept the information, and it will tell the user about the error. Any help is appreciated. My PHP <?php include ('database_connection.php'); if (isset($_POST['formsubmitted'])) { $error = array();//Declare An Array to store any error message if (empty($_POST['name'])) {//if no name has been supplied $error[] = 'Please Enter a name ';/

This question already has an answer here: How do I remove repeated elements from ArrayList? 38 answers I have a very lengthy ArrayList comprised of objects some of them however, are undoubtedly duplicates. What is the best way of finding and removing these duplicates. Note: I have written a boolean-returning compareObjects() method. Example List<Item> result = new ArrayList<Item>(); Set<String> titles = new HashSet<String>(); for( Item item : originalList ) { if( titles.add( item.getTitle() ) { result.add( item ); } } Reference Set Java Data Structures ashes999 You mentioned writing a

I've got a List<string> that contains duplicates and I need to find the indexes of each. What is the most elegant, efficient way other than looping through all the items. I'm on .NET 4.0 so LINQ is an option. I've done tons of searching and connect find anything. Sample data: var data = new List<string>{"fname", "lname", "home", "home", "company"}(); I need to get the indexes of "home". You can create an object from each item containing it's index, then group on the value and filter out the groups containing more than one object. Now you have a grouping list with objects containing the text

I have a python list: [ (2,2),(2,3),(1,4),(2,2), etc...] What I need is some kind of function that reduces it to its unique components... which would be, in the above list: [ (2,2),(2,3),(1,4) ] numpy unique does not quite do this. I can think of a way to do it--convert my tuples to numbers, [22,23,14,etc.] , find the uniques, and work back from there...but I don't know if the complexity won't get out of hand. Is there a function that will do what I am trying to do with tuples? Here is a sample of code that demonstrates the problem: import numpy as np x = [(2,2),(2,2),(2,3)] y = np.unique(x)

I've declared a constant with the same name in some different classes, in their .m file, this way: @implementation MyViewController const NSInteger numberOfItems = 6; ... @end But I get a "duplicate symbol" error when trying to build the project. I've found several posts dealing with this issue regarding extern or global constants, but what I'd want is just declaring some constants private to their class, how can I do that? Thanks If you want to use constant only in one .m file then declare it as static . For example: static NSString * const CONSTANT_STRING = @"Constant I am" . In case of

Possible Duplicate: Find duplicate records in MySQL I have a table in MySQL like this: ID name email 1 john abc@abc.com 2 johnny abc@abc.com 3 jim eee@eee.com 4 Michael abec@awwbc.com How can I have the MySQL query that will list out the duplicate one like this? Result of duplicate search: ID name email Duplicate 1 john abc@abc.com 2 2 johnny abc@abc.com 2 SELECT a.*, b.totalCount AS Duplicate FROM tablename a INNER JOIN ( SELECT email, COUNT(*) totalCount FROM tableName GROUP BY email ) b ON a.email = b.email WHERE b.totalCount >= 2 SQLFiddle Demo for better performance, add an INDEX on