Algorithm
Exchange a range of values in one location with those in another
#include <algorithm>
template <class ForwardIterator1, class ForwardIterator2>
ForwardIterator2 swap_ranges (ForwardIterator1 first1,
ForwardIterator1 last1,
ForwardIterator2 first2);
The swap_ranges algorithm exchanges corresponding values in two ranges, in the following manner:
For each non-negative integer n < (last - first) the function exchanges *(first1 + n) with *(first2 + n)). After completing all exchanges, swap_ranges returns an iterator that points to the end of the second container, i.e., first2 + (last1 -first1). The result of swap_ranges is undefined if the two ranges [first, last) and [first2, first2 + (last1 - first1)) overlap.
//
// swap.cpp
//
#include <vector>
#include <algorithm>
int main()
{
int d1[] = {6, 7, 8, 9, 10, 1, 2, 3, 4, 5};
// Set up a vector
vector<int> v(d1,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
<< "Swapping the first five elements "
<< "with the last five gives: "
<< endl << " ";
copy(v.begin(),v.end(),ostream_iterator<int>(cout," "));
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, you need to always supply the Allocator template argument. For instance, you will need to write :
vector<int, allocator>
instead of :
vector<int>