int p(int year) {
	return (int)((double)year + floor(year/4) - floor(year/100) + floor(year/400)) % 7;
}

int is_long_year(int year) {
	return p(year) == 4 || p(year - 1) == 3;
}

void print_long_years(int from, int to) {
	for (int year = from; year <= to; ++year) {
		if (is_long_year(year)) {
			printf(, year);
		}
	}
}

int main() {

	printf();
	print_long_years(1800, 2100);
	printf();
	return 0;
}