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hash_set::empty

Tests if a hash_set is empty.

bool empty( ) const;

Return Value

true if the hash_set is empty; false if the hash_set is nonempty.

Remarks

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_empty.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, hs2;
   hs1.insert ( 1 );

   if ( hs1.empty( ) )
      cout << "The hash_set hs1 is empty." << endl;
   else
      cout << "The hash_set hs1 is not empty." << endl;

   if ( hs2.empty( ) )
      cout << "The hash_set hs2 is empty." << endl;
   else
      cout << "The hash_set hs2 is not empty." << endl;
}

The hash_set hs1 is not empty.
The hash_set hs2 is empty.

Requirements

Header: <hash_set>

Namespace: stdext

See Also

Concepts

hash_set Class

hash_set Members

Standard Template Library