The sample code below illustrates how to use the reverse_copy
STL function in Visual C++.
Required Header:
<algorithm>
template<class BidirectionalIterator, class OutputIterator> inline
OutputIterator reverse_copy(BidirectionalIterator first,
BidirectionalIterator last,
OutputIterator result)
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_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.
Sample Code:
//////////////////////////////////////////////////////////////////////
//
// Compile options needed: /GX
//
// reverse_copy.cpp : 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 ;
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) ;
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 \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
// and copy the results to Reversed_Twister
reverse_copy(start, end, RTstart) ;
cout << "After calling reverse_copy: \n"
<< endl ;
// print content of Tongue_Twister
cout << "Tongue_Twister: " ;
for(it = start; it != end; it++)
cout << *it << " " ;
cout << "\n\n" ;
// print content of Reversed_Twister
cout << "Now try the reversed Tongue Twister: " ;
for(it = RTstart; it != RTend; it++)
cout << *it << " " ;
cout << "\n\n" ;
}
Program Output is:
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