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reverse_copy (STL Samples)

Illustrates how to use the reverse_copy Standard Template Library (STL) function in Visual C++.

template<class BidirectionalIterator, class OutputIterator> inline
   OutputIterator reverse_copy(
      BidirectionalIterator First,
      BidirectionalIterator Last,
      OutputIterator Result
   )

Remarks

Nota

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

The reverse_copy algorithm reverses the order of the elements in the range [First, Last) and copies the result into a sequence of the same size starting at Result. It returns an iterator positioned immediately after the last new element in the resulting sequence.

Example

// reverse_copy.cpp
// compile with: /EHsc
// Illustrates how to use the reverse_copy function.
//
// Functions:
//    reverse_copy - Reverse a sequence, copy the results to another
//                   same-sized sequence.
//
//////////////////////////////////////////////////////////////////////

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

#include <iostream>
#include <vector>
#include <string>
#include <algorithm>
#include <functional>

using namespace std ;

int main()
{
    const int VECTOR_SIZE = 8 ;

    // Define a template class vector of strings
    typedef vector<string> StrVector ;

    //Define an iterator for template class vector of strings
    typedef StrVector::iterator StrVectorIt ;

    StrVector Tongue_Twister(VECTOR_SIZE) ;
    StrVector Reversed_Twister(VECTOR_SIZE) ;

    StrVectorIt start, end, it, RTstart, RTend ;

    start = Tongue_Twister.begin() ; // location of first
                                     // element of Tongue_Twister

    end = Tongue_Twister.end() ;     // one past the location last
                                     // element of Tongue_Twister

    RTstart = Reversed_Twister.begin() ; // location of first
                                         // element of Reversed_Twister

    RTend = Reversed_Twister.end() ; // one past the location last
                                     // element of Reversed_Twister

    //Initialize vector Tongue_Twister
    Tongue_Twister[0] = "she";
    Tongue_Twister[1] = "sells";
    Tongue_Twister[2] = "sea";
    Tongue_Twister[3] = "shells";
    Tongue_Twister[4] = "by";
    Tongue_Twister[5] = "the";
    Tongue_Twister[6] = "sea";
    Tongue_Twister[7] = "shore";

    cout << "Before calling reverse_copy" << endl ;

    // print content of Tongue_Twister
    cout << "Try this Tongue Twister:";
    for(it = start; it != end; it++)
        cout << " " << *it;

    // reverse the items in the vector Tongue_Twister
    // and copy the results to Reversed_Twister
    reverse_copy(start, end, RTstart);

    cout << "\n\nAfter calling reverse_copy" << endl ;

    // print content of Tongue_Twister
    cout << "Tongue_Twister: ";
    for(it = start; it != end; it++)
        cout << *it << " ";

    // print content of Reversed_Twister
    cout << "\n\nNow try the reversed Tongue Twister:" ;
    for(it = RTstart; it != RTend; it++)
        cout << " " << *it;
}

Output

Before calling reverse_copy
Try this Tongue Twister: she sells sea shells by the sea shore

After calling reverse_copy
Tongue_Twister: she sells sea shells by the sea shore 

Now try the reversed Tongue Twister: shore sea the by shells sea sells she

Requirements

Header: <algorithm>

See Also

Concepts

Standard Template Library Samples