#include <iostream>
#include <cstdlib>
#include <chrono>   //for class system_clock
#include <ctime>    //for the function localtime and structure tm
using namespace std;

/*
p is a pointer to a structure of type tm.
Because of the *const, p always points to the same structure.
Because of the other const, we cannot use p to change the vales of the fields of
the structure.
Day of week is 0 for Sunday, 1 for Monday, etc.
Day of year is 0 for Jan 1, 1 for Jan 2, etc.
*/

int main()
{
	const auto now {chrono::system_clock::now()};
	const time_t t {chrono::system_clock::to_time_t(now)};
        const tm *const p {localtime(&t)};

	cout << "t = " << t << "\n\n";

	//Output the fields of the structure that p points to.
	
	cout << "The current year is " << p->tm_year + 1900 << ".\n";
	cout << "The current month (1 to 12) is " << p->tm_mon + 1 << ".\n";
	cout << "The current day (1 to 31) is " << p->tm_mday << ".\n\n";

	cout << "This is day number " << p->tm_yday << " of the year.\n";
	cout << "This is day number " << p->tm_wday << " of the week.\n\n";

	cout << "The current hour (0 to 23) is " << p->tm_hour << ".\n";
	cout << "The current minute (0 to 59) is " << p->tm_min << ".\n";
	cout << "The current second (0 to 61) is " << p->tm_sec << ".\n\n";

	if (p->tm_isdst >= 0) {
		cout << "Daylight Savings Time is ";
		if (p->tm_isdst == 0) {
			cout << "not ";
		}
		cout << "in effect.\n";
	}

	return EXIT_SUCCESS;
}