examples/manual/multimap.cpp

/**************************************************************************
 *
 * multimap.cpp - Example program for multimap class.
 *
 * $Id: //stdlib/dev/examples/stdlib/manual/multimap.cpp#11 $
 *
 ***************************************************************************
 *
 * Copyright (c) 1994-2005 Quovadx,  Inc., acting through its  Rogue Wave
 * Software division. Licensed under the Apache License, Version 2.0 (the
 * "License");  you may  not use this file except  in compliance with the
 * License.    You    may   obtain   a   copy   of    the   License    at
 * http://www.apache.org/licenses/LICENSE-2.0.    Unless   required    by
 * applicable law  or agreed to  in writing,  software  distributed under
 * the License is distributed on an "AS IS" BASIS,  WITHOUT WARRANTIES OR
 * CONDITIONS OF  ANY KIND, either  express or implied.  See  the License
 * for the specific language governing permissions  and limitations under
 * the License.
 * 
 **************************************************************************/

#include <iostream>   // for cout, ostream
#include <map>        // for multimap
#include <string>     // for string

#include <examples.h>


typedef std::multimap<int, std::string, std::less<int>,
                      std::allocator<std::pair<const int, std::string> > >
months_type;


// Print out a multimap.
inline std::ostream&
operator<< (std::ostream &out, const months_type &m)
{
    for (months_type::const_iterator it = m.begin (); it != m.end (); ++it)
        std::cout << (*it).second << " has " << (*it).first << " days\n";

    return out;
}


int main ()
{
    // Create a multimap of months and the number of days in the month.
    months_type months;

    typedef months_type::value_type value_type;

    // Put the months in the multimap with the number of days
    // as the not necessarily unique key. 
    months.insert (value_type (31, std::string ("January")));
    months.insert (value_type (28, std::string ("Febuary")));
    months.insert (value_type (31, std::string ("March")));
    months.insert (value_type (30, std::string ("April")));
    months.insert (value_type (31, std::string ("May")));
    months.insert (value_type (30, std::string ("June")));
    months.insert (value_type (31, std::string ("July")));
    months.insert (value_type (31, std::string ("August")));
    months.insert (value_type (30, std::string ("September")));
    months.insert (value_type (31, std::string ("October")));
    months.insert (value_type (30, std::string ("November")));
    months.insert (value_type (31, std::string ("December")));

    // Print out the months.
    std::cout << "All months of the year\n" << months << std::endl;

    // Find all months with 30 days.
    std::pair<months_type::iterator, months_type::iterator> p = 
        months.equal_range (30);

    // Print out the 30 day months.
    std::cout << "\nMonths with 30 days\n";

    for ( ; p.first != p.second; ++p.first)
        std::cout << (*p.first).second << '\n';

    return 0;
}