DOCUMENT:Q156618 07-MAY-2001 [visualc] TITLE :STL Sample for the count Function PRODUCT :Microsoft C Compiler PROD/VER:winnt: OPER/SYS: KEYWORDS:_IK ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - The Standard C++ Library, included with: - *EDITOR Please do not choose this product*Microsoft Visual C++ 32-bit Edition* use 241, 265, 225, version 4.2 ------------------------------------------------------------------------------- SUMMARY ======= The sample code below illustrates how to use the count STL function in Visual C++. MORE INFORMATION ================ Required Header --------------- Prototype --------- template inline
template inline size_t count(InputIterator first, InputIterator last, const T& value) 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 count algorithm counts the number of elements in the range [first, last +1) that match value and returns the number of matching elements. Sample Code ----------- ////////////////////////////////////////////////////////////////////// // // Compile options needed: /GX // // count.cpp : Illustrates how to use the count function. // // Functions: // // count - Count items in a range that match a value. // // 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 #include #include #include #include using namespace std; void main() { const int VECTOR_SIZE = 8 ; // Define a template class vector of strings typedef vector > StringVector ; //Define an iterator for template class vector of strings typedef StringVector::iterator StringVectorIt ; StringVector NamesVect(VECTOR_SIZE) ; //vector containing names string value("Sea") ; // stores the value used // to count matching elements StringVectorIt start, end, it ; int result = 0 ; // stores count of elements // that match value. // Initialize vector NamesVect NamesVect[0] = "She" ; NamesVect[1] = "Sells" ; NamesVect[2] = "Sea" ; NamesVect[3] = "Shells" ; NamesVect[4] = "by" ; NamesVect[5] = "the" ; NamesVect[6] = "Sea" ; NamesVect[7] = "Shore" ; start = NamesVect.begin() ; // location of first // element of NamesVect end = NamesVect.end() ; // one past the location // last element of NamesVect // print content of NamesVect cout << "NamesVect { " ; for(it = start; it != end; it++) cout << *it << " " ; cout << " }\n" << endl ; // Count the number of elements in the range [first, last +1) // that match value. result = count(start, end, value) ; // print the count of elements that match value cout << "Number of elements that match \"Sea\" = " << result << endl ; } Program Output is: NamesVect { She Sells Sea Shells by the Sea Shore } Number of elements that match "Sea" = 2 REFERENCES ========== Visual C++ Books On Line: Visual C++ Books:C/C++:Standard C++ Library Reference. Additional query words: STL count ====================================================================== Keywords : _IK Technology : kbVCsearch kbAudDeveloper kbVCLibrary Version : winnt: Issue type : kbhowto ============================================================================= THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY. Copyright Microsoft Corporation 2001.