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Showing content from https://en.cppreference.com/w/cpp/algorithm/../symbol_index/../algorithm/ranges/swap_ranges.html below:

std::ranges::swap_ranges, std::ranges::swap_ranges_result - cppreference.com

Call signature

(1) (since C++20) (2) (since C++20)

Helper types

(3) (since C++20)

The ranges [first1, last1) and [first2, last2) must not overlap.

The function-like entities described on this page are algorithm function objects (informally known as niebloids), that is:

[edit] Parameters first1, last1 - the iterator-sentinel pair defining the first range of elements to swap first2, last2 - the iterator-sentinel pair defining the second range of elements to swap r1 - the first range of elements to swap r2 - the second range of elements to swap. [edit] Return value

{first1 + M, first2 + M}.

[edit] Complexity

Exactly M swaps.

[edit] Notes

Implementations (e.g. MSVC STL) may enable vectorization when the iterator type models contiguous_iterator and swapping its value type calls neither non-trivial special member function nor ADL-found swap.

[edit] Possible implementation 
struct swap_ranges_fn
{
    template<std::input_iterator I1, std::sentinel_for<I1> S1,
             std::input_iterator I2, std::sentinel_for<I2> S2>
    requires std::indirectly_swappable<I1, I2>
    constexpr ranges::swap_ranges_result<I1, I2>
        operator()(I1 first1, S1 last1, I2 first2, S2 last2) const
    {
        for (; !(first1 == last1 or first2 == last2); ++first1, ++first2)
            ranges::iter_swap(first1, first2);
        return {std::move(first1), std::move(first2)};
    }
 
    template<ranges::input_range R1, ranges::input_range R2>
    requires std::indirectly_swappable<ranges::iterator_t<R1>, ranges::iterator_t<R2>>
    constexpr ranges::swap_ranges_result<ranges::borrowed_iterator_t<R1>,
                                         ranges::borrowed_iterator_t<R2>>
        operator()(R1&& r1, R2&& r2) const
    {
        return (*this)(ranges::begin(r1), ranges::end(r1),
                       ranges::begin(r2), ranges::end(r2));
    }
};
 
inline constexpr swap_ranges_fn swap_ranges {};
[edit] Example 
#include <algorithm>
#include <iostream>
#include <list>
#include <string_view>
#include <vector>
 
auto print(std::string_view name, auto const& seq, std::string_view term = "\n")
{
    std::cout << name << " : ";
    for (const auto& elem : seq)
        std::cout << elem << ' ';
    std::cout << term;
}
 
int main()
{
    std::vector<char> p {'A', 'B', 'C', 'D', 'E'};
    std::list<char> q {'1', '2', '3', '4', '5', '6'};
 
    print("p", p);
    print("q", q, "\n\n");
 
    // swap p[0, 2) and q[1, 3):
    std::ranges::swap_ranges(p.begin(),
                             p.begin() + 4,
                             std::ranges::next(q.begin(), 1),
                             std::ranges::next(q.begin(), 3));
    print("p", p);
    print("q", q, "\n\n");
 
    // swap p[0, 5) and q[0, 5):
    std::ranges::swap_ranges(p, q);
 
    print("p", p);
    print("q", q);
}

Output:

p : A B C D E
q : 1 2 3 4 5 6
 
p : 2 3 C D E
q : 1 A B 4 5 6
 
p : 1 A B 4 5
q : 2 3 C D E 6
[edit] See also swaps the values referenced by two dereferenceable objects
(customization point object)[edit] swaps the values of two objects
(customization point object)[edit] swaps two ranges of elements
(function template) [edit] swaps the elements pointed to by two iterators
(function template) [edit] swaps the values of two objects
(function template) [edit]

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