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multiset::rbegin

Returns an iterator addressing the first element in a reversed multiset.

const_reverse_iterator rbegin( ) const; 
reverse_iterator rbegin( );

Return Value

A reverse bidirectional iterator addressing the first element in a reversed multiset or addressing what had been the last element in the unreversed multiset.

Remarks

rbegin is used with a reversed multiset just as rbegin is used with a multiset.

If the return value of rbegin is assigned to a const_reverse_iterator, then the multiset object cannot be modified. If the return value of rbegin is assigned to a reverse_iterator, then the multiset object can be modified.

rbegin can be used to iterate through a multiset backwards.

Example

// multiset_rbegin.cpp
// compile with: /EHsc
#include <set>
#include <iostream>

int main( )
{
   using namespace std;   
   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;
}
The first element in the reversed multiset is 30.
The multiset is: 10 20 30
The reversed multiset is: 30 20 10
After the erasure, the first element in the reversed multiset is 20.

Requirements

Header: <set>

Namespace: std

See Also

Reference

multiset Class

Standard Template Library