chapter9-8.cpp

STL程序员开发指南源码

//文件名:CHAPTER9-8.cpp
#include <set>
#include <iostream>
#if _MSC_VER > 1020   // if VC++ version is > 4.2
   using namespace std;  // std c++ libs implemented in std
#endif
int main( )
{
   multiset <int> ms1;
   multiset <int>::iterator ms1_Iter;
   multiset <int>::reverse_iterator ms1_rIter;
   ms1.insert( 10 );
   ms1.insert( 20 );
   ms1.insert( 30 );
   ms1_rIter = ms1.rbegin( );
   cout << "The first element in the reversed multiset is "
        << *ms1_rIter << "." << endl;
   // begin can be used to start an interation throught a multiset in a forward order
   cout << "The multiset is:";
   for ( ms1_Iter = ms1.begin( ) ; ms1_Iter != ms1.end( ); ms1_Iter++ )
      cout << " " << *ms1_Iter;
   cout << endl;
   // rbegin can be used to start an interation throught a multiset in a reverse order
   cout << "The reversed multiset is:";
   for ( ms1_rIter = ms1.rbegin( ) ; ms1_rIter != ms1.rend( ); ms1_rIter++ )
      cout << " " << *ms1_rIter;
   cout << endl;
   // A multiset element can be erased by dereferencing to its key 
   ms1_rIter = ms1.rbegin( );
   ms1.erase ( *ms1_rIter );
   ms1_rIter = ms1.rbegin( );
   cout << "After the erasure, the first element "
        << "in the reversed multiset is "<< *ms1_rIter << "." 
        << endl;
}