operator< (hash_set)
Tests if the hash_set object on the left side of the operator is less than the hash_set object on the right side.
bool operator<(
const hash_set <Key, Traits, Allocator>& _Left,
const hash_set <Key, Traits, Allocator>& _Right
);
Parameters
_Left
An object of type hash_set._Right
An object of type hash_set.
Return Value
true if the hash_set on the left side of the operator is strictly less than the hash_set on the right side of the operator; otherwise false.
Remarks
The comparison between hash_set objects is based on a pairwise comparison of their elements. The less-than relationship between two objects is based on a comparison of the first pair of unequal elements.
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_op_lt.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, hs3;
int i;
for ( i = 0 ; i < 3 ; i++ )
{
hs1.insert ( i );
hs2.insert ( i * i );
hs3.insert ( i - 1 );
}
if ( hs1 < hs2 )
cout << "The hash_set hs1 is less than the hash_set hs2." << endl;
else
cout << "Hash_set hs1 is not less than hash_set hs2." << endl;
if ( hs1 < hs3 )
cout << "The hash_set hs1 is less than the hash_set hs3." << endl;
else
cout << "Hash_set hs1 is not less than hash_set hs3." << endl;
}
The hash_set hs1 is less than the hash_set hs2.
Hash_set hs1 is not less than hash_set hs3.
Requirements
Header: <hash_set>
Namespace: stdext