// ------- test-std2.cpp beg ---------
// 
// Using STL, Standard Template Library for C++.
// Testing hash_map (dictionary) datatype.
// 
// This example is a reprint of
//  http://gcc.gnu.org/onlinedocs/libstdc++/faq/index.html#5_4
//  http://www.icce.rug.nl/documents/cplusplus/cplusplus12.html

// This is how to compile and run this code:
// g++ -Wall test-std2.cpp -o test-std2
// ./test-std2

#include <string>
#include <ext/hash_map>
#include <iostream>

// For std::cin, std::out
using namespace std;

// Create namespace alias to reach the hash_map classes
namespace stdext = ::__gnu_cxx;

// This class' function operator() generates a hash value.
// Unique hash values (indeces) provide quickest access to data.

/* struct or */
class HashString
{
public:
   /*long*/ int operator()(std::string const &str) const
   {
     return stdext::hash<char const *>()(str.c_str());
   }
};

// This class' function operator() tests if two keys are equal

/* struct or */
class HashStringCompare
{
 public:
   bool operator()(std::string  s1, std::string  s2) const
   {
     return s1 == s2;
   }
};

// ------------------------------------------

int main()
{
   // This hash_map dictionary will contain month names(=keys) and days(=values)
   stdext::hash_map<string, int, HashString, HashStringCompare> months;
 
   months["january"] = 31;
   months["february"] = 28;
   months["march"] = 31;
   months["april"] = 30;
   months["may"] = 31;
   months["june"] = 30;
   months["july"] = 31;
   months["august"] = 31;
   months["september"] = 30;
   months["october"] = 31;
   months["november"] = 30;
   months["december"] = 31;
     
   cout << "september -> " << months["september"] << endl <<
           "april     -> " << months["april"] << endl <<
           "june      -> " << months["june"] << endl <<
           "november  -> " << months["november"] << endl;

   // Ok
   return 0;
 }

// ------- test-std2.cpp end ---------