std::chrono::weekday_last::weekday_last(3)

NAME
std::chrono::weekday_last::weekday_last - std::chrono::weekday_last::weekday_last

Synopsis
   constexpr explicit weekday_last( const std::chrono::weekday& wd ) (since C++20)
   noexcept;
   Constructs a weekday_last object storing the weekday wd.

Notes
   A more convenient way to construct a weekday_last is with weekday's operator[],
   i.e., wd[std::chrono::last].

Example
// Run this code
 #include <chrono>
 #include <iostream>
 using namespace std::chrono;
 int main()
 {
     const year_month_day ymd{floor<days>(system_clock::now())};
     const weekday_last wdl{Sunday[last]}; // A last Sunday of a month
     const year_month_day last_sun{ymd.year() / ymd.month() / wdl};
     std::cout << "The last Sunday of current month falls on "
               << (int)last_sun.year() << '/'
               << (unsigned)last_sun.month() << '/'
               << (unsigned)last_sun.day() << '\n';
 }

Possible output:
 The last Sunday of current month falls on 2021/9/26