iter_swap(std::common_iterator)

#include <algorithm>
#include <iostream>
#include <iterator>
#include <string>
#include <vector>
 
int main()
{
 std::vector <std::string > v1{"1", "2", "3", "4", "5"},
 v2{"α", "β", "γ", "δ", "ε"};
 
 using CI = std::common_iterator <
 std::counted_iterator <std::vector <std::string >::iterator>,
 std::default_sentinel_t
 >;
 
 CI first1{std::counted_iterator {v1.begin(), 3}};
 CI first2{std::counted_iterator {v2.begin(), 4}};
 CI last{std::default_sentinel };
 
 auto print = [&](auto rem)
 {
 std::cout << rem << "v1 = ";
 std::ranges::copy (v1, std::ostream_iterator <std::string >{std::cout, " "});
 std::cout << "\nv2 = ";
 std::ranges::copy (v2, std::ostream_iterator <std::string >{std::cout, " "});
 std::cout << '\n';
 };
 
 print("Before iter_swap:\n");
 
 for (; first1 != last && first2 != last; ++first1, ++first2)
 iter_swap(first1, first2); // ADL
 
 print("After iter_swap:\n");
}

Before iter_swap:
v1 = 1 2 3 4 5 
v2 = α β γ δ ε 
After iter_swap:
v1 = α β γ 4 5 
v2 = 1 2 3 δ ε