std::map<std::string, uint32_t> dictionary
std::set<const std::string *> keySet;
// std::back_inserter(keyVector)
std::transform(dictionary.begin(), dictionary.end(), std::inserter(keySet, keySet.end()), [](std::pair<const std::string, uint32_t> &pair)
{ return &(pair.first); });
//----------------------
标签：std,map,dictionary,inserter,C++,keySet,pair
From： https://www.cnblogs.com/gispathfinder/p/17000577.html