for_each (STL Sample)
The sample code below illustrates how to use the for_each STL function in Visual C++.

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: 

//////////////////////////////////////////////////////////////////////
//
// 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.
//////////////////////////////////////////////////////////////////////

// disable warning C4786: symbol greater than 255 character,
// okay to ignore
#pragma warning(disable: 4786)

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

using namespace std;


// 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 > 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" ;
}

 
Program Output is:

Numbers { 1 2 3 4 5 6 7 8  }

1 8 27 64 125 216 343 512