Iterator Creation
Each container generates its suitable iterator on request. For example an std::unordered_map generates constant and non-constant forward iterators.
std::unordered_map<std::string, int>::iterator unMapIt= unordMap.begin();
std::unordered_map<std::string, int>::iterator unMapIt= unordMap.end();
std::unordered_map<std::string, int>::const_iterator unMapIt= unordMap.cbegin();
std::unordered_map<std::string, int>::const_iterator unMapIt= unordMap.cend();
In addition, std::map supports the backward iterators:
std::map<std::string, int>::reverse_iterator mapIt= map.rbegin();
std::map<std::string, int>::reverse_iterator mapIt= map.rend();
std::map<std::string, int>::const_reverse_iterator mapIt= map.rcbegin();
std::map<std::string, int>::const_reverse_iterator mapIt= map.rcend();
