c++ - 'sqrt' is not a member of 'std' -


i compile program in linux - has following line :

std::sqrt((double)num);

on windows ok,but on linux 'sqrt' not member of 'std' have include math.h

what problem it?

change directive #include <cmath>. c++ headers of form <cxxxxxxx> guaranteed have standard names in std namespace (and may optionaly provide them in global namespace). <xxxxxx.h> not.


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