STL Sample for the Predicate Version of max_element Function

ID: Q156992

The information in this article applies to:

The Standard C++ Library included with: - Microsoft Visual C++, 32-bit Edition, version 4.2

SUMMARY

The sample code below illustrates how to use the predicate version of the max_element STL function in Visual C++.

MORE INFORMATION

Required Header

   <algorithm>

Prototype

   template<class InputIterator, class Compare> inline
       InputIterator max_element(InputIterator first,
                                 InputIterator last,
                                 Compare compare)

NOTE: The class/parameter names in the prototype do not match the original version in the header file. They have been modified to improve readability.

Description

The max_element algorithm returns the location of the maximum element in the sequence [first, last).

The predicate version of max_element uses compare function for comparisons.

Sample Code

////////////////////////////////////////////////////////////////////// 
// 
// Compile options needed: /GX
// 
// max_element.cpp : Illustrates how to use the predicates version
//                   of the max_element function.
// 
// Functions:
// 
//    max_element : Return the maximum element within a range.
// 
// Written by Kalindi Sanghrajka
// of Microsoft Product Support Services,
// Software Core Developer Support.
// Copyright (c) 1996 Microsoft Corporation. All rights reserved.
////////////////////////////////////////////////////////////////////// 

// disable warning C4786: symbol greater than 255 character,
// okay to ignore

#pragma warning(disable: 4786)

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

void main()

{

    const int VECTOR_SIZE = 8 ;

    // Define a template class vector of int
    typedef vector<int, allocator<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 maximum element in the Numbers
    location = max_element(start, end, less<int>()) ;

    cout << "The maximum element in Numbers is: "
        << *location << endl ;
}

Program Output is:

Numbers { 4 10 10 30 69 70 96 100 }

The maximum element in Numbers is: 100

REFERENCES

Visual C++ Books On Line: Visual C++ Books:C/C++:Standard C++ Library Reference.

Additional query words: STL STLSample max_element

Keywords          : kbcode STLIss 
Version           : WINNT:4.2;
Platform          : NT WINDOWS
Issue type        : kbhowto

Last Reviewed: October 10, 1997