Re: searching in set vs. vector
Mehturt@gmail.com ha scritto:
I have made a test on GNU/Linux using g++ 4.0 comparing searches in
std::vector<int> and std::set<int> and it seems searches in sorted
vector are faster only for small sizes (about 10 elements), for
anything bigger std::set<int> is much faster (the more elements, the
greater the difference). I mean I'm using std::set<> and std::map<>
not only to store sorted data, but only to have fast searches in the
container.. The memory usage is not really a case for me..
How did you search in the std::vector? Aren't you, by chance, comparing
std::set find with a linear search in std::vector with std::find, for
example? Of course, as you already sorted the vector, you can (and
should) use a binary search algorithm like std::lower_bound, in order to
get any benefit from the sorted vector approach.
HTH,
Ganesh
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