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Tree data structure in C#

...e so many ways you could implement it that it would be impossible to cover all bases with one solution. The more specific a solution, the less likely it is applicable to any given problem. I even get annoyed with LinkedList - what if I want a circular linked list? The basic structure you'll need ...
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How do I get the opposite (negation) of a Boolean in Python?

...ful if you want to use a function that requires a predicate-function or a callback. For example map or filter: >>> lst = [True, False, True, False] >>> list(map(operator.not_, lst)) [False, True, False, True] >>> lst = [True, False, True, False] >>> list(filter...
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What is the difference between '/' and '//' when used for division?

...floating point division, and the latter is floor division, sometimes also called integer division. In Python 2.2 or later in the 2.x line, there is no difference for integers unless you perform a from __future__ import division, which causes Python 2.x to adopt the 3.x behavior. Regardless of the ...
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Why is it slower to iterate over a small string than a small list?

...nd with timeit and noticed that doing a simple list comprehension over a small string took longer than doing the same operation on a list of small single character strings. Any explanation? It's almost 1.35 times as much time. ...
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How to run code when a class is subclassed? [duplicate]

...- Watcher subclasses type, not object. 2 - SuperClass has no superclass at all, not object. I'm just so used to writing down object as a superclass for every class I defined that I somehow missed it that this code was using something else. Although there doesn't seem to be any harm in making SuperCl...
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NOT using repository pattern, use the ORM as is (EF)

... The more I started digging I started asking myself the question: "Do I really need it?" 9 Answers ...
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How to Batch Rename Files in a macOS Terminal?

...g). If you find yourself batch-renaming files frequently, consider installing a specialized tool such as the Perl-based rename utility. On macOS you can install it using popular package manager Homebrew as follows: brew install rename Here's the equivalent of the command at the top using rena...
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Undocumented NSURLErrorDomain error codes (-1001, -1003 and -1004) using StoreKit

... All error codes are on "CFNetwork Errors Codes References" on the documentation (link) A small extraction for CFURL and CFURLConnection Errors: kCFURLErrorUnknown = -998, kCFURLErrorCancelled = -999, kCFURLErrorBadU...
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Understanding the main method of python [duplicate]

...n other programs, and also include code to evaluate only when the file is called as a standalone script. It's important to understand that all of the code above the if __name__ line is being executed, evaluated, in both cases. It's evaluated by the interpreter when the file is imported or when it'...
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PDO closing connection

... close the connection, you need to destroy the object by ensuring that all remaining references to it are deleted--you do this by assigning NULL to the variable that holds the object. If you don't do this explicitly, PHP will automatically close the connection when your script ends. Note...