KB158578 - How to use the set::rbegin and set::rend STL functions in Visual C++

MORE INFORMATION

Required Header

   <set>

Prototype

   template<class _K, class _Pr, class _A>
   class set {
   public:
   // Function 1:

      const_reverse_iterator rbegin() const;

   // Function 2:
      const_reverse_iterator rend() const;
   }

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

Description

The rbegin function returns a reverse bidirectional iterator that points just beyond the end of the controlled sequence. The rend function returns a reverse bidirectional iterator that points at the first element of the sequence.

Sample Code

////////////////////////////////////////////////////////////////////// 
// 
// Compile options needed: -GX
// 
// SetRbeginRend.cpp:
//      Illustrates how to use the rbegin function to get a reverse
//      bidirectional iterator that points just beyond the end of
//      the controlled sequence. It also illustrates how to use
//      the rend function to get a reverse bidirectional iterator
//      that points at the first element of the sequence.
// 
// Functions:
// 
//    rbegin      Returns a reverse bidirectional iterator that points
//                just beyond the end of the controlled sequence.
//    rend        Returns a reverse bidirectional iterator that points
//                at the first element of the sequence.
// 
// Written by Derek Jamison
// of Microsoft Technical Support,
// Copyright (c) 1996 Microsoft Corporation. All rights reserved.
////////////////////////////////////////////////////////////////////// 

#pragma warning(disable:4786)

#include <set>
#include <iostream>

#if _MSC_VER > 1020   // if VC++ version is > 4.2
   using namespace std;  // std c++ libs implemented in std
   #endif

typedef set<int,less<int>,allocator<int> > SET_INT;

void main() {

  SET_INT s1;
  SET_INT::reverse_iterator i;
  cout << "s1.insert(5)" << endl;
  s1.insert(5);
  cout << "s1.insert(10)" << endl;
  s1.insert(10);
  cout << "s1.insert(15)" << endl;
  s1.insert(15);
  cout << "s1.insert(20)" << endl;
  s1.insert(20);

  // displays: 20,15,10,5

  for (i=s1.rbegin();i!=s1.rend();i++)

     cout << "s1 has " << *i << " in its set." << endl;

}

Program Output

s1.insert(5)
s1.insert(10)
s1.insert(15)
s1.insert(20)
s1 has 20 in its set.
s1 has 15 in its set.
s1 has 10 in its set.
s1 has 5 in its set.

How to use the set::rbegin and set::rend STL functions in Visual C++

SUMMARY