map::upper_bound
Returns an iterator to the first element in a 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 map being searched.
Return Value
An iterator or const_iterator that addresses the location of an element in a map that with a key that is greater than the argument key, or that addresses the location succeeding the last element in the map if no match is found for the key.
If the return value is assigned to a const_iterator, the map object cannot be modified. If the return value is assigned to a iterator, the map object can be modified.
Example
// map_upper_bound.cpp
// compile with: /EHsc
#include <map>
#include <iostream>
int main( )
{
using namespace std;
map <int, int> m1;
map <int, int> :: const_iterator m1_AcIter, m1_RcIter;
typedef pair <int, int> Int_Pair;
m1.insert ( Int_Pair ( 1, 10 ) );
m1.insert ( Int_Pair ( 2, 20 ) );
m1.insert ( Int_Pair ( 3, 30 ) );
m1_RcIter = m1.upper_bound( 2 );
cout << "The first element of map m1 with a key "
<< "greater than 2 is: "
<< m1_RcIter -> second << "." << endl;
// If no match is found for the key, end is returned
m1_RcIter = m1. upper_bound ( 4 );
if ( m1_RcIter == m1.end( ) )
cout << "The map m1 doesn't have an element "
<< "with a key greater than 4." << endl;
else
cout << "The element of map m1 with a key > 4 is: "
<< m1_RcIter -> second << "." << endl;
// The element at a specific location in the map can be found
// using a dereferenced iterator addressing the location
m1_AcIter = m1.begin( );
m1_RcIter = m1. upper_bound ( m1_AcIter -> first );
cout << "The 1st element of m1 with a key greater than\n"
<< "that of the initial element of m1 is: "
<< m1_RcIter -> second << "." << endl;
}
The first element of map m1 with a key greater than 2 is: 30. The map m1 doesn't have an element with a key greater than 4. The 1st element of m1 with a key greater than that of the initial element of m1 is: 20.
Requirements
Header: <map>
Namespace: std