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The upper bound algorithm returns the last location in the sequence that value can be

The upper bound algorithm returns the last location in the sequence that value can be


upper_bound
	
 
Header
<algorithm>

template<class ForwardIterator, class T> inline 
ForwardIterator upper_bound(ForwardIterator first, ForwardIterator last, const T& value)

The upper_bound algorithm returns the last location in the sequence that value can be inserted such that the order of the sequence is maintained. upper_bound returns an iterator positioned at the location that value can be inserted in the range [first..last), or returns last if no such position exists. upper_bound assumes the range [first ..last) is sorted using operator<.

template<class ForwardIterator, class T, class Compare> inline 
ForwardIterator upper_bound(ForwardIterator first, ForwardIterator last, const T& value, Compare compare)

The upper_bound algorithm returns the last location in the sequence that value can be inserted such that the order of the sequence [first..last) is maintained. upper_bound returns an iterator positioned at the location that value can be inserted in the range [first..last), or returns last if no such position exists. This version assumes the range [first..last) is sorted sequentially using the compare function.


Samples
Sample for Non-Predicate Version

// disable warning C4786: symbol greater than 255 character,
// okay to ignore
#pragma warning(disable: 4786)

#include <iostream>
#include <algorithm>
#include <functional>
#include <vector>

using namespace std;


void main()
{
    const int VECTOR_SIZE = 8 ;

    // Define a template class vector of int
    typedef vector<int > IntVector ;

    //Define an iterator for template class vector of strings
    typedef IntVector::iterator IntVectorIt ;

    IntVector Numbers(VECTOR_SIZE) ;

    IntVectorIt start, end, it, location ;

    // Initialize vector Numbers
    Numbers[0] = 4 ;
    Numbers[1] = 10;
    Numbers[2] = 10 ;
    Numbers[3] = 30 ;
    Numbers[4] = 69 ;
    Numbers[5] = 70 ;
    Numbers[6] = 96 ;
    Numbers[7] = 100;

    start = Numbers.begin() ;   // location of first
                                // element of Numbers

    end = Numbers.end() ;       // one past the location
                                // last element of Numbers

    // print content of Numbers
    cout << "Numbers { " ;
    for(it = start; it != end; it++)
        cout << *it << " " ;
    cout << " }\n" << endl ;

    //return the last location at which 10 can be inserted
    // in Numbers
    location = upper_bound(start, end, 10) ;

    cout << "Element 10 can be inserted at index "
        << location - start << endl ;
}

Program Output

Numbers { 4 10 10 30 69 70 96 100  }

Element 10 can be inserted at index 3

Sample for Predicate Version

// disable warning C4786: symbol greater than 255 character,
// okay to ignore
#pragma warning(disable: 4786)

#include <iostream>
#include <algorithm>
#include <functional>
#include <vector>

using namespace std;


void main()
{
    const int VECTOR_SIZE = 8 ;

    // Define a template class vector of int
    typedef vector<int > IntVector ;

    //Define an iterator for template class vector of strings
    typedef IntVector::iterator IntVectorIt ;

    IntVector Numbers(VECTOR_SIZE) ;

    IntVectorIt start, end, it, location ;

    // Initialize vector Numbers
    Numbers[0] = 4 ;
    Numbers[1] = 10;
    Numbers[2] = 70 ;
    Numbers[3] = 10 ;
    Numbers[4] = 30 ;
    Numbers[5] = 69 ;
    Numbers[6] = 96 ;
    Numbers[7] = 100;

    start = Numbers.begin() ;   // location of first
                                // element of Numbers

    end = Numbers.end() ;       // one past the location
                                // last element of Numbers

    //sort Numbers using the function object less<int>()
    //upper_bound assumes that Numbers is sorted
    //using the "compare" (less<int>() in this case)
    //function
    sort(start, end, less<int>()) ;

    // print content of Numbers
    cout << "Numbers { " ;
    for(it = start; it != end; it++)
        cout << *it << " " ;
    cout << " }\n" << endl ;

    //return the highest location at which 10 can be inserted
    // in Numbers
    location = upper_bound(start, end, 10, less<int>()) ;

    cout << "Last location  for element 10 in Numbers is: "
        << location - start << endl ;
}

Program Output

Numbers { 4 10 10 30 69 70 96 100  }

Last location  for element 10 in Numbers is: 3