C++ Tutorial/map multimap/multimap count

Count keys in multimap

<source lang="cpp">#include <iostream> using std::cout; using std::endl;

1. 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;

}</source>

There are currently 0 pairs with key 15 in the multimap
After inserts, there are 2 pairs with key 15