I guess this is a simple question. I need to do something like this:
std::set<int> s1, s2;
s1 = getAnExcitingSet();
std::transform(s1.begin(), s1.end(), std::back_inserter(s2), ExcitingUnaryFunctor());
Of course, std::back_inserter
doesn't work since there's no push_back
.
std::inserter
also needs an iterator? I haven't used std::inserter
so I'm not sure what to do.
Does anyone have an idea?
s2
, and then just sort it later. Maybe that's better?
set
doesn't have push_back
because the position of an element is determined by the comparator of the set. Use std::inserter
and pass it .begin()
:
std::set<int> s1, s2;
s1 = getAnExcitingSet();
transform(s1.begin(), s1.end(),
std::inserter(s2, s2.begin()), ExcitingUnaryFunctor());
The insert iterator will then call s2.insert(s2.begin(), x)
where x
is the value passed to the iterator when written to it. The set uses the iterator as a hint where to insert. You could as-well use s2.end()
.