// https://godbolt.org/z/zMqjqMeav
#include <chrono>
#include <iostream>
using namespace std::chrono;
int main() {
year y{2021};
std::cout << y << "\n";
month m{October};
auto result = m + months{3}; // 'months', not 'month': 3 months later
std::cout << result << "\n"; // overflowed to January
weekday wd{Thursday};
auto result = wd + days{4}; // 'days', not 'day': 4 days later
std::cout << result << "\n"; // overflowed to Monday
weekday sun1{0}; // 0 is Sunday
weekday sun2{7}; // 7 is also Sunday
std::cout << sun1 << "\t" << sun2 << "\n";
weekday_indexed wdi{wd, 4}; // unspecified 4th Thursday
std::cout << wdi << "\n"; // Output: Thu[4] — as given by chrono
// unspecified values
}