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

const int sun {1 << 0};   //00000000000000000000000000000001
const int mon {1 << 1};   //00000000000000000000000000000010
const int tue {1 << 2};   //00000000000000000000000000000100
const int wed {1 << 3};   //00000000000000000000000000001000
const int thu {1 << 4};   //00000000000000000000000000010000
const int fri {1 << 5};   //00000000000000000000000000100000
const int sat {1 << 6};   //00000000000000000000000001000000

struct dining_option {       
	string name;
	int days;       //what day(s) of the week this restaurant is open
};

void f(const dining_option *p, int  current_day);

int main()
{
	const dining_option a[] {
		{"Argo Tea",             mon | tue | wed | thu |       sat},
		{"Community Dining Hall",mon | tue | wed | thu | fri | sat|sun},
		{"Ram Caf",              mon | tue | wed | thu |       sat}
	};
	const size_t n {size(a)};   //the number of elements in the array
	
	//Ask the operating system for the current day of the week.
	const time_t t {time(nullptr)};
	const tm *const localTime {localtime(&t)};
        const int current_day {localTime->tm_wday};   //day of week (0-6)

	//Pass the address of each structure to the function f.
	for (int i {0}; i < n; ++i) {
		f(a+i, current_day);   //a+i means &a[i]
	}

	return EXIT_SUCCESS;
}

//Check if the bit for current_day is turned on in p->days.

void f(const dining_option *p, int current_day)
{
	cout << p->name << " is ";
	if (p->days >> current_day & 1) {
		cout << "open";
	} else {
		cout << "closed";
	}
	cout << " today.\n";
}