iter_swap

     Algorithm

Exchange values pointed at in two locations

Contents

• Synopsis
• Description
• Example
• Warning
• See Also

#include <algorithm>

template <class ForwardIterator1, class ForwardIterator2>
void iter_swap (ForwardIterator1, ForwardIterator2);

The iter_swap algorithm exchanges the values pointed at by the two iterators a and b.

#include <vector>
#include <algorithm>
#include <iostream.h>
 int main ()
 {
   int d1[] = {6, 7, 8, 9, 10, 1, 2, 3, 4, 5};
   //
   // Set up a vector.
   //
   vector<int> v(d1+0, d1+10);
   //
   // Output original vector.
   //
   cout << "For the vector: ";
   copy(v.begin(), v.end(), ostream_iterator<int>(cout," "));
   //
   // Swap the first five elements with the last five elements.
   //
   swap_ranges(v.begin(), v.begin()+5, v.begin()+5);
   //
   // Output result.
   //
   cout << endl << endl
        << "Swaping the first 5 elements with the last 5 gives: "
        << endl << "     ";
   copy(v.begin(), v.end(), ostream_iterator<int>(cout," "));
   //
   // Now an example of iter_swap -- swap first and last elements.
   //
   iter_swap(v.begin(), v.end()-1);
   //
   // Output result.
   //
   cout << endl << endl
        << "Swaping the first and last elements gives: "
        << endl << "     ";
   copy(v.begin(), v.end(), ostream_iterator<int>(cout," "));
   cout << endl;
   return 0;
 }
Output :
For the vector: 6 7 8 9 10 1 2 3 4 5
Swaping the first five elements with the last five gives:
     1 2 3 4 5 6 7 8 9 10
Swaping the first and last elements gives:
     10 2 3 4 5 6 7 8 9 1

If your compiler does not support default template parameters, then you will need to always supply the Allocator template argument. For instance, you'll have to write :

vector<int, allocator>

instead of :

vector<int>

Iterators, swap, swap_ranges