#include <boost/intrusive/unordered_set.hpp>
#include <vector>
#include <functional>
#include <boost/functional/hash.hpp>
#include <iostream>
 
using namespace boost::intrusive;
 
class MyClass : public unordered_set_base_hook<>
{               //This is a derivation hook
   int int_;
 
   public:
   unordered_set_member_hook<> member_hook_; //This is a member hook
 
   MyClass(int i)
      :  int_(i)
   {}
 
   friend bool operator== (const MyClass &a, const MyClass &b)
   {  return a.int_ == b.int_;  }
 
   friend std::size_t hash_value(const MyClass &value)
   {  return std::size_t(value.int_); }
};
 
//Define an unordered_set that will store MyClass objects using the base hook
typedef unordered_set<MyClass>    BaseSet;
 
//Define an unordered_multiset that will store MyClass using the member hook
typedef member_hook<MyClass, unordered_set_member_hook<>, &MyClass::member_hook_>
   MemberOption;
typedef unordered_multiset< MyClass, MemberOption>  MemberMultiSet;
 
int main()
{
   for (int i = 0; i < 33; i++)
		std::cout << "i: " << i << ". Suggested: " << BaseSet::suggested_upper_bucket_count(i) << std::endl;
   return 0;
}

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