#include <iostream>
#include <cstdlib>
using namespace std;

//Output the date of Easter in the western churches
//for any year in the range 1583 to 99999 AD inclusive.
//From Donald E. Knuth, "The Art of Computer Programming,
//Volume 1: Fundamental Algorithms", 2nd ed. (1973), pp. 155-156.

int main()
{
	const int year {2025};
	if (year <= 1582 || year >= 100000) {
		cerr << "Sorry, year is out of range.\n";
		return EXIT_FAILURE;
	}

	const int golden {year % 19 + 1};   //Metonic cycle
	const int century {year / 100 + 1}; //the century that contains the year

	const int x {3 * century / 4 - 12}; //# of times leap year cancelled
	const int z {(8 * century + 5) / 25 - 5};    //sync with Moon's orbit

	const int day {5 * year / 4 - x - 10};

	int epact {(11 * golden + 20 + z - x) % 30}; //age of moon on Jan 1
	if (epact < 0) {
		epact += 30;    //Make sure the epact is non-negative.
	}
	if (epact == 24 || epact == 25 && golden > 11) {
		++epact;
	}

	int n {44 - epact};     //The nth day of March is a full moon.
	if (n < 21) {           //March 21 is the vernal equinox.
		n += 30;        //Get the full moon after the equinox.
	}

	n += 7 - (day + n) % 7; //Advance to the next Sunday.

	cout << "Easter is on Sunday, ";
	if (n <= 31) {
		cout << "March " << n;
	} else {
		cout << "April " << n - 31;
	}
	cout << ", " << year << ".\n";

	return EXIT_SUCCESS;
}