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hash_set::begin

Returns an iterator that addresses the first element in the hash_set.

const_iterator begin( ) const; 
iterator begin( );

Return Value

A bidirectional iterator addressing the first element in the hash_set or the location succeeding an empty hash_set.

Remarks

If the return value of begin is assigned to a const_iterator, the elements in the hash_set object cannot be modified. If the return value of begin is assigned to an iterator, the elements in the hash_set object can be modified.

In Visual C++ .NET 2003, members of the <hash_map> and <hash_set> header files are no longer in the std namespace, but rather have been moved into the stdext namespace. See The stdext Namespace for more information.

Example

// hash_set_begin.cpp
// compile with: /EHsc
#define _DEFINE_DEPRECATED_HASH_CLASSES 0
#include <hash_set>
#include <iostream>

int main( )
{
   using namespace std;
   using namespace stdext;
   hash_set <int> hs1;
   hash_set <int>::iterator hs1_Iter;
   hash_set <int>::const_iterator hs1_cIter;
   
   hs1.insert( 1 );
   hs1.insert( 2 );
   hs1.insert( 3 );

   hs1_Iter = hs1.begin( );
   cout << "The first element of hs1 is " << *hs1_Iter << endl;

   hs1_Iter = hs1.begin( );
   hs1.erase( hs1_Iter );

   // The following 2 lines would err because the iterator is const
   // hs1_cIter = hs1.begin( );
   // hs1.erase( hs1_cIter );

   hs1_cIter = hs1.begin( );
   cout << "The first element of hs1 is now " << *hs1_cIter << endl;
}

The first element of hs1 is 1
The first element of hs1 is now 2

Requirements

Header: <hash_set>

Namespace: stdext

See Also

Concepts

hash_set Class

hash_set Members

Standard Template Library