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What is the difference between a heuristic and an algorithm?
What is the difference between a heuristic and an algorithm?
12 Answers
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PHP validation/regex for URL
I've been looking for a simple regex for URLs, does anybody have one handy that works well? I didn't find one with the zend framework validation classes and have seen several implementations.
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Is it wrong to use Deprecated methods or classes in Java?
...ting warnings at some places that methods are deprecated, but the code is working fine.
15 Answers
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How to create custom exceptions in Java? [closed]
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To define a checked exception you create a subclass (or hierarchy of subclasses) of java.lang.Exception. For example:
public class FooException extends Exception {
public FooException() { super(); }
public FooException(String message) { super(message); }
public FooExcep...
Tuples( or arrays ) as Dictionary keys in C#
... of values to one string. I tried using arrays as keys, but that did not work, and I don't know what else to do. At this point I am considering making a Dictionary of Dictionaries of Dictionaries, but that would probably not be very pretty to look at, though it is how I would do it in javascript.
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AngularJS : Difference between the $observe and $watch methods
...serve('attr1', ...).
(If you try scope.$watch(attrs.attr1, ...) it won't work because of the {{}}s -- you'll get undefined.) Use $watch for everything else.
$watch() is more complicated. It can observe/watch an "expression", where the expression can be either a function or a string. If the expr...
The difference between bracket [ ] and double bracket [[ ]] for accessing the elements of a list or
R provides two different methods for accessing the elements of a list or data.frame: [] and [[]] .
12 Answers
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Swift native base class or NSObject
I tested out some isa swizzling with Swift, and found that it only works when NSObject is a super-class (directly or further up), or by using the '@objc' decoration. Otherwise it will follow a static- and vtable-dispatch style, like C++.
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What is better, adjacency lists or adjacency matrices for graph problems in C++?
What is better, adjacency lists or adjacency matrix, for graph problems in C++?
What are the advantages and disadvantages of each?
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Can you explain the concept of streams?
...m is a representation of a sequence of bytes. Each stream provides means for reading and writing bytes to its given backing store. But what is the point of the stream? Why isn't the backing store itself what we interact with?
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