Article: Q156345
Product(s): Microsoft C Compiler
Version(s): 4.2,5.0,6.0
Operating System(s):
Keyword(s): kbcode kbVC420 kbVC500 kbVC600 kbDSupport
Last Modified: 26-MAR-2002
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The information in this article applies to:
- The Standard C++ Library, used with:
- Microsoft Visual C++, 32-bit Enterprise Edition, versions 4.2, 5.0, 6.0
- Microsoft Visual C++, 32-bit Professional Edition, versions 4.2, 5.0, 6.0
- Microsoft Visual C++, 32-bit Learning Edition, version 6.0
- Microsoft Visual C++.NET (2002)
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SUMMARY
=======
The sample code below illustrates how to use the for_each, begin, and end STL
function in Visual C++.
MORE INFORMATION
================
Required Header
---------------
<algorithm>
Prototype
---------
template<class InputIterator, class Function> inline
Function for_each(InputIterator first,
InputIterator last,
Function F)
NOTE: The class/parameter names in the prototype do not match the version in the
header file. Some have been modified to improve readability.
Description
-----------
The for_each algorithm calls Function F for each element in the range [first,
last) and returns the input parameter F. This function does not modify any
elements in the sequence.
Sample Code
-----------
NOTE: In the first line of the sample code section, /GX is equivalent to /EHsc in
VC++ .NET and is set by default.
//////////////////////////////////////////////////////////////////////
//
// Compile options needed: /GX
//
// count.cpp : Illustrates how to use the for_each function.
//
// Functions:
//
// for_each - Calls function F for every element in a range.
//
// begin - Returns an iterator that points to the first element
// in a sequence.
//
// end - Returns an iterator that points one past the end of
// a sequence.
//
// 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 <vector>
#include <algorithm>
#if _MSC_VER > 1020 // if VC++ version is > 4.2
using namespace std; // std c++ libs implemented in std
#endif
// prints the cube of integer n
void PrintCube(int n)
{
cout << n * n * n << " " ;
}
void main()
{
const int VECTOR_SIZE = 8 ;
// Define a template class vector of integers
typedef vector<int, allocator<int> > IntVector ;
//Define an iterator for template class vector of integer
typedef IntVector::iterator IntVectorIt ;
IntVector Numbers(VECTOR_SIZE) ; //vector containing numbers
IntVectorIt start, end, it ;
int i ;
// Initialize vector Numbers
for (i = 0; i < VECTOR_SIZE; i++)
Numbers[i] = i + 1 ;
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 ;
// for each element in the range [first, last)
// print the cube of the element
for_each(start, end, PrintCube) ;
cout << "\n\n" ;
}
Output:
Numbers { 1 2 3 4 5 6 7 8 }
1 8 27 64 125 216 343 512
REFERENCES
==========
Visual C++ Books On Line: Visual C++ Books:C/C++:Standard C++ Library Reference.
Additional query words: STL STLSample for_each begin end
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Keywords : kbcode kbVC420 kbVC500 kbVC600 kbDSupport
Technology : kbVCsearch kbAudDeveloper kbVCNET kbVCLibrary
Version : :4.2,5.0,6.0
Issue type : kbinfo
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