c++ - What's the memory complexity of std::sort() and std::sort_heap()? -



c++ - What's the memory complexity of std::sort() and std::sort_heap()? -

as in title - what's memory complexity of std::sort() , std::sort_heap()? (the latter requires std::make_heap() i'd know memory complexity well.)

i've tried searching on these sites: http://www.cplusplus.com/reference/ http://en.cppreference.com/w/ either missed or mention time complexity. memory complexity of said functions specified anywhere (in c++ standard or other document)? or maybe implementation-dependent?

for std::sort() found reply on cboard, pretty much says:

quality of implementation issue. different implementations utilize memory more other implementations. beyond that, standard allows specializations std::sort different iterators categories allowing implementation take between few different options long complexity (time) matches requirements. complexity given not time, numbers of comparisons. implementation perform n³ swap operations.

the memory overhead implementations of std::sort related depth of recursion , number of local variables stored onto stack each level of recursion. hp / microsoft stl implementation of std::sort uses quicksort until/unless detects recursion level getting deep in case switches heap sort. if size small, such 32 or less, uses insertionsort.

you can see comparing of algorithms, in wikipedia page , estimate memory complexity.

similarly, suspect other 2 algorithms fall same case.

c++ c++11 big-o c++-standard-library space-complexity

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