c++ - Replace vector and hash table with Boost.Bimap -

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i'm looking replace vector<string> , boost::unordered_map<string, size_t> mapping string indices in former boost::bimap.

what instantiation of bimap should use? far, i've come with

typedef bimap<     unordered_set_of<size_t>,     vector_of<string> > stringmap;

but i'm not sure if i've reversed collection types now. also, wonder if should change collection of relations type. vector_of_relation best choice, or set_of_relation, or go default?

to bimap between size_t , std::string have ~constant (up cost of hashing , potential clashes) need use unordered_set_of:

#include <boost/bimap.hpp> #include <boost/bimap/unordered_set_of.hpp> #include <string> #include <iostream> #include <typeinfo>  int main(int argc, char* argv[]) {    typedef boost::bimap< boost::bimaps::unordered_set_of<size_t>, boost::bimaps::unordered_set_of<std::string> > stringmap;   stringmap map;   map.insert(stringmap::value_type(1,std::string("cheese")));   map.insert(stringmap::value_type(2,std::string("cheese2")));    typedef stringmap::left_map::const_iterator const_iter_type;   const const_iter_type end = map.left.end();    ( const_iter_type iter = map.left.begin(); iter != end; iter++ ) {     std::cout << iter->first << " " << map.left.at(iter->first) << "\n";   }  }

returns:

1 cheese 2 cheese2

the unordered_set boost version of set uses hash tables instead of trees store elements, see boost unordered docs.

looking @ comments 1 of bimap examples @ bimap example, have:

the left map view works std::unordered_map< std::string, long >, given name of country can use search population in constant time


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