reverse (STL Sample)

The sample code below illustrates how to use the reverse STL function in Visual C++.

Required Header:
<algorithm>

template<class BidirectionalIterator> inline
     void reverse(BidirectionalIterator first, BidirectionalIterator last)

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 reverse algorithm reverses the order of the elements in the range [first, last).

Sample Code:

//////////////////////////////////////////////////////////////////////
//
// Compile options needed: /GX
//
// reverse.cpp : Illustrates how to use the reverse function.
//
// Functions:
//
//    reverse - Reverse the items in a 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;


void 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) ;

    StrVectorIt start, end, it ;

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

    end = Tongue_Twister.end() ;       // one past the location last
                                       // element of Tongue_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 \n" << endl ;

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

    // reverse the items in the vector Tongue_Twister
     reverse(start, end) ;

     cout << "After calling reverse \n" << endl ;

    // print content of Tongue_Twister
    cout << "Now try the reversed Tongue Twister: " ;
    for(it = start; it != end; it++)
        cout << *it << " " ;
    cout << "\n\n" ;

}

 

Program Output is:

Before calling reverse

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

After calling reverse

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