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std::vector performance regression when enabling C++11
I have found an interesting performance regression in a small C++ snippet, when I enable C++11:
1 Answer
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How to “perfectly” override a dict?
...or other builtins) directly. It often makes no sense, because what you actually want to do is implement the interface of a dict. And that is exactly what ABCs are for.
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How to implement a good __hash__ function in python [duplicate]
... are equal. It also shouldn't change over the lifetime of the object; generally you only implement it for immutable objects.
A trivial implementation would be to just return 0. This is always correct, but performs badly.
Your solution, returning the hash of a tuple of properties, is good. But note...
Hashing a dictionary?
...e hash():
hash(frozenset(my_dict.items()))
This is much less computationally intensive than generating the JSON string or representation of the dictionary.
UPDATE: Please see the comments below, why this approach might not produce a stable result.
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What are the rules about using an underscore in a C++ identifier?
...FC background, you'll probably use m_foo . I've also seen myFoo occasionally.
5 Answers
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Bidirectional 1 to 1 Dictionary in C#
...turn firstToSecond.Count; }
}
/// <summary>
/// Removes all items from the dictionary.
/// </summary>
public void Clear()
{
firstToSecond.Clear();
secondToFirst.Clear();
}
}
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How to identify platform/compiler from preprocessor macros?
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I'm sorry, but this answer is quite incorrect on all accounts and doesn't even answer the question.
– rubenvb
Jan 27 '15 at 20:13
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split string only on first instance of specified character
...Very elegant. Works like a charm. Thank you.
– Ofeargall
Jan 5 '11 at 18:43
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Just to be clear, ...
How can I open multiple files using “with open” in Python?
I want to change a couple of files at one time, iff I can write to all of them. I'm wondering if I somehow can combine the multiple open calls with the with statement:
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Objective-C ARC: strong vs retain and weak vs assign
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@Pascal: weak references aren't allowed in deployment targets where the os is not 5.0 or higher. So for older projects you can still use assign, but if you move to newer versions you have to switch to weak
– Mattia
Feb...