iter_swap (STL Samples)
Illustrates how to use the iter_swap Standard Template Library (STL) function in Visual C++.
template<class ForwardIterator1, class ForwardIterator2> inline
void iter_swap(
ForwardIterator1 First,
ForwardIterator2 Second
)
Remarks
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 iter_swap algorithm swaps two elements represented by two iterators.
Example
// iter_swap.cpp
// compile with: /EHsc
//
// Functions:
// iter_swap - Swap two elements in a sequence represented by
// two iterators.
//
// 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 characters
// okay to ignore
#pragma warning(disable: 4786)
#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
// return the next Fibonacci number in the
// Fibonacci series.
int Fibonacci(void)
{
static int r;
static int f1 = 0;
static int f2 = 1;
r = f1 + f2 ;
f1 = f2 ;
f2 = r ;
return f1 ;
}
int 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 ;
start = Numbers.begin() ; // location of first
// element of Numbers
end = Numbers.end() ; // one past the location
// last element of Numbers
// fill the range [first, last +1) with a series of
// Fibonacci numbers using the Fibonacci function
generate(start, end, Fibonacci) ;
cout << "Before calling iter_swap" << endl ;
// print content of Numbers
cout << "Numbers { " ;
for(it = start; it != end; it++)
cout << *it << " " ;
cout << " }\n" << endl ;
// swap the first and last elements of the
// sequence using iter_swap
iter_swap(start, end - 1) ;
cout << "After calling iter_swap" << endl ;
// print content of Numbers
cout << "Numbers { " ;
for(it = start; it != end; it++)
cout << *it << " " ;
cout << " }\n" << endl ;
}
Before calling iter_swap
Numbers { 1 1 2 3 5 8 13 21 }
After calling iter_swap
Numbers { 21 1 2 3 5 8 13 1 }
Requirements
Header: <algorithm>