| swap_ranges |
function template |
template < class ForwardIterator1, class ForwardIterator2 >
ForwardIterator2 swap_ranges ( ForwardIterator1 first1, ForwardIterator1 last1,
ForwardIterator2 first2 ); |
<algorithm> |
Exchange values of two ranges
Swaps the values of each of the elements in the range [first1,last1) with those of their respective elements in the range beginning at first2.
The behavior of this function template is equivalent to:
template<class ForwardIterator1, class ForwardIterator2>
ForwardIterator2 swap_ranges ( ForwardIterator1 first1, ForwardIterator1 last1,
ForwardIterator2 first2 )
{
while (first1!=last1) swap(*first1++, *first2++);
return first2;
}
|
Parameters
- first1, last1
- Forward iterators to the initial and final positions in one of the sequences to be swapped. The range used is [first1,last1), which contains all the elements between first1 and last1, including the element pointed by first1 but not the element pointed by last1.
- first2
- Forward iterator to the initial position in the other sequence to be swapped. The range used includes the same number of elements as the range [first1,last1).
The two ranges shall not overlap.
Return value
An iterator to the last element swapped in the second sequence.
Example
// swap_ranges example
#include <iostream>
#include <algorithm>
#include <vector>
using namespace std;
int main () {
vector<int> first (5,10); // first: 10 10 10 10 10
vector<int> second (5,33); // second: 33 33 33 33 33
vector<int>::iterator it;
swap_ranges(first.begin()+1, first.end()-1, second.begin());
// print out results of swap:
cout << " first contains:";
for (it=first.begin(); it!=first.end(); ++it)
cout << " " << *it;
cout << "\nsecond contains:";
for (it=second.begin(); it!=second.end(); ++it)
cout << " " << *it;
cout << endl;
return 0;
}
|
Output:
first contains: 10 33 33 33 10
second contains: 10 10 10 33 33
|
Complexity
Linear: Performs as many swaps as elements are in the range
[first1,last1).
See also
| swap | Exchange values of two objects (function template) |
| iter_swap | Exchange values of objects pointed by two iterators (function template) |
| replace | Replace value in range (function template) |
