How to use the list::merge STL function in Visual C++ (168045)


The information in this article applies to:

  • The Standard C++ Library, when used with:
    • Microsoft Visual C++, 32-bit Enterprise Edition 4.2
    • Microsoft Visual C++, 32-bit Enterprise Edition 5.0
    • Microsoft Visual C++, 32-bit Enterprise Edition 6.0
    • Microsoft Visual C++, 32-bit Professional Edition 4.2
    • Microsoft Visual C++, 32-bit Professional Edition 5.0
    • Microsoft Visual C++, 32-bit Professional Edition 6.0
    • Microsoft Visual C++, 32-bit Learning Edition 6.0
    • Microsoft Visual C++ .NET (2002)
    • Microsoft Visual C++ .NET (2003)
    • Microsoft Visual C++ 2005 Express Edition
This article was previously published under Q168045
Note Microsoft Visual C++ .NET 2002 and Microsoft Visual C++ .NET 2003 support both the managed code model that is provided by the Microsoft .NET Framework and the unmanaged native Microsoft Windows code model. The information in this article applies only to unmanaged Visual C++ code. Microsoft Visual C++ 2005 supports both the managed code model that is provided by the Microsoft .NET Framework and the unmanaged native Microsoft Windows code model.

SUMMARY

The sample code below illustrates how to use the [list::merge] STL function(s) in Visual C++.

Note that there are some differences in the implementation of the Standard C++ Library components in Visual C++ version 4.2 versus later revisions. The relevant sections of code below compile conditionally based upon the value of _MSC_VER.

MORE INFORMATION

Required Header

   <list>
   <iostream>

Prototype

   void merge(list& x);
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

This example shows how to merge two sorted lists.

Sample Code

   ////////////////////////////////////////////////////////////////////// 
   // 
   // Compile options needed: -GX
   // 
   // merge.cpp :  This example show how to merge two sorted list<T>s.
   // 
   // Functions:
   // 
   //  list::merge
   // 
   // Written by Andrew Bradnan
   // Copyright (c) 1996 Microsoft Corporation. All rights reserved.
   ////////////////////////////////////////////////////////////////////// 

   #include <list>
   #include <iostream>
   using namespace std;

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


   typedef list<int, allocator<int> > LISTINT;

   void main()
   {
      // List's must be sorted first
      int list1[] = {12,11,10,7,6,5,3,1};
      int list2[] = {22,21,20,10,7,6,5};

      LISTINT test1;
      LISTINT test2;
      LISTINT::iterator i;

      test1.insert (test1.begin(), list1, list1 + 8);
      test2.insert (test2.begin(), list2, list2 + 7);

      test1.merge (test2);

      // 22 21 20 12 11 10 10 7 7 6 6 5 5 3 1
      for (i = test1.begin(); i != test1.end(); ++i)
         cout << *i << " ";
      cout << endl;
   }

Program Output

   12 11 10 7 6 5 3 1 22 21 20 10 7 6 5

REFERENCES

Visual C++ Books On Line: Visual C++ Books:C/C++:Standard C++ Library Reference.
Modification Type:MajorLast Reviewed:1/9/2006
Keywords:kbcode kbhowto KB168045 kbAudDeveloper
©2004 Microsoft Corporation. All rights reserved.