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map vs. hash_map in C++
I have a question with hash_map and map in C++. I understand that map is in STL, but hash_map is not a standard. What's the difference between the two?
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What does 'const static' mean in C and C++?
I saw this in some code here on StackOverflow and I couldn't figure out what it does. Then I saw some confused answers on other forums. My best guess is that it's used in C to hide the constant foo from other modules. Is this correct? If so, why would anyone use it in a C++ context where you can j...
How to “perfectly” override a dict?
..._contains__
# free setdefault, __eq__, and so on
import pickle
# works too since we just use a normal dict
assert pickle.loads(pickle.dumps(s)) == s
I wouldn't subclass dict (or other builtins) directly. It often makes no sense, because what you actually want t...
In Python, when to use a Dictionary, List or Set?
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A list keeps order, dict and set don't: when you care about order, therefore, you must use list (if your choice of containers is limited to these three, of course;-).
dict associates with each key a value, while list and set just contain values: ver...
What is the basic difference between the Factory and Abstract Factory Design Patterns? [closed]
What is the basic difference between the Factory and Abstract Factory Patterns?
19 Answers
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Can you explain the HttpURLConnection connection process?
... a web service. I know how to use HTTPURLConnection but I want to understand how it works. Basically, I want to know the following:
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When should we use intern method of String on String literals
...in String pool, otherwise a new string object will be added in String pool and the reference of this String is returned.
1...
Array.Copy vs Buffer.BlockCopy
Array.Copy and Buffer.BlockCopy both do the same thing, but BlockCopy is aimed at fast byte-level primitive array copying, whereas Copy is the general-purpose implementation. My question is - under what circumstances should you use BlockCopy ? Should you use it at any time when you are copyi...
NHibernate vs LINQ to SQL
...orld projects I wonder if anyone knows how these two complement each other and how much their functionalities overlap?
9 An...
Why is SSE scalar sqrt(x) slower than rsqrt(x) * x?
I've been profiling some of our core math on an Intel Core Duo, and while looking at various approaches to square root I've noticed something odd: using the SSE scalar operations, it is faster to take a reciprocal square root and multiply it to get the sqrt, than it is to use the native sqrt opcode!...
