rotate_copy (STL Samples)
Visual Studio 2005
Illustrates how to use the rotate_copy Standard Template Library (STL) function in Visual C++.
template<class ForwardIterator, class OutputIterator> inline
OutputIterator rotate_copy(
BidirectionalIterator First,
BidirectionalIterator Middle,
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. |
The rotate_copy algorithm rotates the elements in the range [First, Last) to the right by n positions (where n = Middle - First), 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.
| Note |
|---|
| The OutputIterator should be different from the sequence to be rotated. If they are the same, the result will depend on the implementation. |
// rotate_copy.cpp
// compile with: /EHsc
// Illustrates how to use the rotate_copy function.
//
// Functions:
// rotate_copy - Rotate a sequence by n positions, 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 Rotated_Twister(VECTOR_SIZE) ;
StrVectorIt start, middle, end, it, RTstart, RTend ;
// location of first element of Tongue_Twister
start = Tongue_Twister.begin() ;
// one past the location last element of Tongue_Twister
end = Tongue_Twister.end() ;
// start position for rotating elements
middle = start + 3 ;
// location of first element of Rotated_Twister
RTstart = Rotated_Twister.begin() ;
// one past the location last element of Rotated_Twister
RTend = Rotated_Twister.end() ;
// 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 rotate_copy:" << endl ;
// print content of Tongue_Twister
cout << "Try this Tongue Twister:" ;
for (it = start; it != end; it++)
cout << " " << *it;
// rotate the items in the vector Tongue_Twist to the right by
// 3 positions and copy the results to Rotated_Twister
rotate_copy(start, middle, end, RTstart) ;
cout << endl << "After calling rotate_copy:" << endl ;
// print content of Tongue_Twister
cout << "Tongue_Twister: " ;
for (it = start; it != end; it++)
cout << " " << *it;
// print content of Rotated_Twister
cout << endl << "Now try the rotated Tongue Twister:" ;
for (it = RTstart; it != RTend; it++)
cout << " " << *it;
cout << endl;
}
