C++ Tutorial/map multimap/multimap

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A multimap can store duplicates

#include <map>
#include <iostream>
using namespace std;
typedef map <int, string> MAP_INT_STRING;
typedef multimap <int, string> MMAP_INT_STRING;
int main ()
{
    MMAP_INT_STRING mmapIntToString;
    mmapIntToString.insert (pair <int, string> (1000, "One Thousand"));
    mmapIntToString.insert (MMAP_INT_STRING::value_type (1000, "Thousand"));
    cout << endl << "The multimap contains " << mmapIntToString.size ();
    cout << " key-value pairs." << endl;
    cout << "The elements in the multimap are: " << endl;

    return 0;
}

Instantiating an STL map and multimap (Key Type: integer, Value Type: string)

#include <map>
#include <string>
int main ()
{
    using namespace std;
    map <int, string> mapIntegersToString;
    multimap <int, string> mmapIntegersToString;
    return 0;
}

make a dictionary out of a multimap

#include <algorithm>
#include <iostream>
#include <map>
#include <utility>
using namespace std;
int main( )
{
   const char* word[] = { "A", "B", "C", "D","E" };
   const char* clue[] = { "a", "b","c", "d","e" };
   map<string,string> dictionary1;
   transform( word, word+sizeof(word)/sizeof(word[0]), clue,inserter( dictionary1, dictionary1.end() ),make_pair<string,string> );
   typedef multimap<string,string> Dictionary;
   Dictionary dictionary2( dictionary1.begin(),dictionary1.end() );
   dictionary2.insert( make_pair( "POPS", "Bursts" ) );
   dictionary2.insert( make_pair( "POPS", "Fathers" ) );
   dictionary2.insert( make_pair( "ADAM", "Madam" ) );
   pair<Dictionary::iterator,Dictionary::iterator> range = dictionary2.equal_range( "POPS" );
   for( Dictionary::iterator i = range.first; i != range.second; ++i )
      cout << "\nPOPS - " << i->second;
   for( Dictionary::iterator i = dictionary2.begin();
      i != dictionary2.end(); ++i )
      cout << i->first << " - " << i->second << endl;
}

multimap can return the number of pairs with the same key

#include <map>
#include <iostream>
using namespace std;
typedef map <int, string> MAP_INT_STRING;
typedef multimap <int, string> MMAP_INT_STRING;
int main ()
{
    MMAP_INT_STRING mmapIntToString;
    mmapIntToString.insert (MMAP_INT_STRING::value_type (3, "Three"));
    mmapIntToString.insert (MMAP_INT_STRING::value_type (45, "Forty Five"));
    cout << "The number of pairs in the multimap with 1000 as their key: "
        << mmapIntToString.count (1000) << endl;
    return 0;
}
Источник — «http://cppe.ru/index.php?title=C%2B%2B_Tutorial/map_multimap/multimap&oldid=2104»