C++ Tutorial/map multimap/multimap insert

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Insert into multimap with key-value pair

#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 << endl << "The multimap contains " << mmapIntToString.size ();
    cout << " key-value pairs." << endl;
    cout << "The elements in the multimap are: " << endl;

    return 0;
}

Insert into multimap with make-pair function

#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 (make_pair (-1, "Minus One"));
    cout << endl << "The multimap contains " << mmapIntToString.size ();
    cout << " key-value pairs." << endl;
    cout << "The elements in the multimap are: " << endl;

    return 0;
}

Insert value pair to int, double multimap

#include <iostream>
using std::cout;
using std::endl;
#include <map>
int main()
{
   std::multimap< int, double, std::less< int > > pairs; // declare the multimap pairs
   cout << "There are currently " << pairs.count( 15 )
      << " pairs with key 15 in the multimap\n";
   // insert two value_type objects in pairs
   pairs.insert( std::multimap< int, double, std::less< int > >::value_type( 15, 2.7 ) );
   pairs.insert( std::multimap< int, double, std::less< int > >::value_type( 15, 99.3 ) );
   cout << "After inserts, there are " << pairs.count( 15 )
      << " pairs with key 15\n\n";
   cout << endl;
   return 0;
}
There are currently 0 pairs with key 15 in the multimap
After inserts, there are 2 pairs with key 15

uses a multimap to store names and phone numbers.

#include <iostream>
#include <map>
#include <string>
using namespace std;
void shownumbers(const char *n, multimap<string, string> mp);
int main()
{
  multimap<string, string> phonemap;
  // Insert elements by using operator[].
  phonemap.insert(pair<string, string>("A", "B: 555-1111"));
  phonemap.insert(pair<string, string>("C", "D: 555-1234"));
  phonemap.insert(pair<string, string>("E", "F: 555-1122"));
  phonemap.insert(pair<string, string>("J", "K: 314 555-2222"));
  phonemap.insert(pair<string, string>("L", "M: 314 555-3322"));
  phonemap.insert(pair<string, string>("O", "P: 666 555-9876"));
  phonemap.insert(pair<string, string>("Q", "R: 555 555-1010"));
  phonemap.insert(pair<string, string>("S", "T: 444 555-9999"));
  shownumbers("A", phonemap);
  shownumbers("C", phonemap);
  shownumbers("E", phonemap);
  int count = phonemap.erase("A");
  cout << count << " elements have been removed.\n\n";
  shownumbers("Ken", phonemap);
  return 0;
}
// Show all numbers for a given name.
void shownumbers(const char *n, multimap<string, string> mmp) {
  multimap<string, string>::iterator itr;
  // Find the first matching key.
  itr = mmp.find(n);
  if(itr != mmp.end()) {
    cout << "the numbers for " << n << ": " << endl;
    do {
      cout << " " << itr->second << endl;
    ++itr;
  } while (itr != mmp.upper_bound(n));
}
else
  cout << "No entry for " << n << " found." << endl;
}
Источник — «http://cppe.ru/index.php?title=C%2B%2B_Tutorial/map_multimap/multimap_insert&oldid=2100»