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What would cause an algorithm to have O(log log n) complexity?
This earlier question addresses some of the factors that might cause an algorithm to have O(log n) complexity.
2 Answers
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How to determine if a number is a prime with regex?
I found the following code example for Java on RosettaCode :
4 Answers
4
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Proper practice for subclassing UIView?
I'm working on some custom UIView-based input controls, and I'm trying to ascertain proper practice for setting up the view. When working with a UIViewController, it's fairly simple to use the loadView and related viewWill , viewDid methods, but when subclassing a UIView, the closest methosds I...
What is the difference between class and instance attributes?
Is there any meaningful distinction between:
5 Answers
5
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How does lucene index documents?
I read some document about Lucene; also I read the document in this link
( http://lucene.sourceforge.net/talks/pisa ).
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In HTML5, should the main navigation be inside or outside the element?
In HTML5, I know that <nav> can be used either inside or outside the page's masthead <header> element. For websites having both secondary and main navigation, it seems common to include the secondary navigation as a <nav> element inside the masthead <header> element ...
What's the difference between EscapeUriString and EscapeDataString?
If only deal with url encoding, I should use EscapeUriString ?
5 Answers
5
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How to create an object for a Django model with a many to many field?
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You cannot create m2m relations from unsaved objects. If you have the pks, try this:
sample_object = Sample()
sample_object.save()
sample_object.users.add(1,2)
Update: After reading the saverio's answer, I decided to investi...
What does the thread_local mean in C++11?
I am confused with the description of thread_local in C++11. My understanding is, each thread has unique copy of local variables in a function. The global/static variables can be accessed by all the threads (possibly synchronized access using locks). And the thread_local variables are visible to...
Strange, unexpected behavior (disappearing/changing values) when using Hash default value, e.g. Hash
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First, note that this behavior applies to any default value that is subsequently mutated (e.g. hashes and strings), not just arrays.
TL;DR: Use Hash.new { |h, k| h[k] = [] } if you want the most idiomatic solution and don’t care why.
What doesn’t work
Why Hash.new([...