#include <iostream>
#include <cstdlib>
#include <string>      
#include <chrono>      
#include <ctime>       
using namespace std;

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)};
	const int weekday {p->tm_wday};

	const string a[]{
		"Sunday",
		"Monday",
		"Tuesday",
		"Wednesday",
		"Thursday",
		"Friday",
		"Saturday",
		
	};

	const size_t n {size(a)};

	if (weekday < 0 || weekday >= n) {
		cerr << "Not a valid response \n";
		return EXIT_FAILURE;
	}

	if (weekday >= 1 && weekday <=5) {
		cout << "It's a " << a[weekday] << "! You have class!\n";
	} else { 
		cout <<"It's a " << a[weekday] << "! Let's party!\n";
	}
	return EXIT_SUCCESS;
}