hash_map::upper_bound
Returns an iterator to the first element in a hash_map that with a key having a value that is greater than that of a specified key.
iterator upper_bound(
const Key& _Key
);
const_iterator upper_bound(
const Key& _Key
) const;
Parameters
- _Key
The argument key value to be compared with the sort key value of an element from the hash_map being searched.
Return Value
An iterator or const_iterator that addresses the location of an element in a hash_map that with a key that is greater than the argument key, or that addresses the location succeeding the last element in the hash_map if no match is found for the key.
If the return value is assigned to a const_iterator, the hash_map object cannot be modified. If the return value is assigned to an iterator, the hash_map object can be modified.
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_map_upper_bound.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;
hash_map <int, int> :: const_iterator hm1_AcIter, hm1_RcIter;
typedef pair <int, int> Int_Pair;
hm1.insert ( Int_Pair ( 1, 10 ) );
hm1.insert ( Int_Pair ( 2, 20 ) );
hm1.insert ( Int_Pair ( 3, 30 ) );
hm1_RcIter = hm1.upper_bound( 2 );
cout << "The first element of hash_map hm1 with a key "
<< "greater than 2 is: "
<< hm1_RcIter -> second << "." << endl;
// If no match is found for the key, end is returned
hm1_RcIter = hm1. upper_bound ( 4 );
if ( hm1_RcIter == hm1.end( ) )
cout << "The hash_map hm1 doesn't have an element "
<< "with a key greater than 4." << endl;
else
cout << "The element of hash_map hm1 with a key > 4 is: "
<< hm1_RcIter -> second << "." << endl;
// The element at a specific location in the hash_map can be found
// using a dereferenced iterator addressing the location
hm1_AcIter = hm1.begin( );
hm1_RcIter = hm1. upper_bound ( hm1_AcIter -> first );
cout << "The 1st element of hm1 with a key greater than "
<< "that\n of the initial element of hm1 is: "
<< hm1_RcIter -> second << "." << endl;
}
The first element of hash_map hm1 with a key greater than 2 is: 30. The hash_map hm1 doesn't have an element with a key greater than 4. The 1st element of hm1 with a key greater than that of the initial element of hm1 is: 20.
Requirements
Header: <hash_map>
Namespace: stdext