std::unordered_map::bucket_count

// unordered_map::bucket_count
#include <iostream>
#include <string>
#include <unordered_map>

int main ()
{
  std::unordered_map<std::string,std::string> mymap = {
            {"house","maison"},
            {"apple","pomme"},
            {"tree","arbre"},
            {"book","livre"},
            {"door","porte"},
            {"grapefruit","pamplemousse"}
  };

  unsigned n = mymap.bucket_count();

  std::cout << "mymap has " << n << " buckets.\n";

  for (unsigned i=0; i<n; ++i) {
    std::cout << "bucket #" << i << " contains: ";
    for (auto it = mymap.begin(i); it!=mymap.end(i); ++it)
      std::cout << "[" << it->first << ":" << it->second << "] ";
    std::cout << "\n";
  }

  return 0;
}