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hash_map::size

Returns the number of elements in the hash_map.

size_type size( ) const;

Return Value

The current length of the hash_map.

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

When compiling this example with the /Wp64 flag or on a 64-bit platform, compiler warning C4267 will be generated. For more information on this warning, see Compiler Warning (level 3) C4267.

// hash_map_size.cpp
// compile with: /EHsc
#define _DEFINE_DEPRECATED_HASH_CLASSES 0
#include <hash_map>
#include <iostream>

int main( )
{
    using namespace std;
    using namespace stdext;
    hash_map<int, int> hm1, hm2;
    hash_map<int, int>::size_type i;
    typedef pair<int, int> Int_Pair;

    hm1.insert(Int_Pair(1, 1));
    i = hm1.size();
    cout << "The hash_map length is " << i << "." << endl;

    hm1.insert(Int_Pair(2, 4));
    i = hm1.size();
    cout << "The hash_map length is now " << i << "." << endl;
}
The hash_map length is 1.
The hash_map length is now 2.

Requirements

Header: <hash_map>

Namespace: stdext

See Also

Reference

hash_map Class

Standard Template Library

Other Resources

hash_map Members