#include <iostream>
#include<cmath>
#include<ctime>
#include<string>
#include <iomanip>
#include <fstream>

using namespace std;

void printMonth(int year, int month);
void printMonthTitle(int year, int month);
void ptintMonthName(int month);
void printMonthBody(int year, int month);
int getStartDay(int year, int month);
int getTotalNumberOfDays(int year, int month);
int getNumberOfDaysInMonth(int year, int month);
bool isLeapYear(int year);

int main()
{
	cout << "Enter full year ";
	int year;
	cin >> year;
	cout << " Enter month in number between 1 and 12: ";
	int month;
	cin >> month;
	printMonth(year, month);

}
void printMonth(int year, int month)
{
	printMonthTitle(year, month);

	printMonthBody(year, month);
}


void printMonthTitle(int year, int month)

{
	ptintMonthName(month);
	cout << " " << year << endl;
	cout << "-----------------------------" << endl;
	cout << " Sun Mon Tue Wed Thu Fri Sat" << endl;
	

}



void ptintMonthName(int month)

{
	switch (month)
	{
	case 1:
		cout << "January";
		break;
	case 2:
		cout << "February";
		break;
	case 3:
		cout << "March";
		break;
	case 4:
		cout << "April";
		break;
	case 5:
		cout << "May";
		break;
	case 6:
		cout << "June";
		break;
	case 7:
		cout << "July";
		break;
	case 8:
		cout << "August";
		break;
	case 9:
		cout << "September";
		break;
	case 10:
		cout << "October";
		break;
	case 11:
		cout << "November";
		break;
	case 12:
		cout << "December";
	}
}
void printMonthBody(int year, int month)
{
	int startDay = getStartDay(year, month);
	int numberOfDaysInMonth = getNumberOfDaysInMonth(year, month);

	for (int i = 0; i < startDay; i++)
		cout << "    ";
	for (int i = 1; i <=  numberOfDaysInMonth; i++)
	{
		cout << setw(4) << i;
		if ((i + startDay) % 7 == 0)
			cout << endl;
	}
}
int getStartDay(int year, int month)
{
	int startDay1800 = 3;
	int totalNumberOfDays = getTotalNumberOfDays(year, month);


	return (totalNumberOfDays + startDay1800) % 7;

}
int getTotalNumberOfDays(int year, int month)
{
	int total = 0;
	for (int i = 1800; i < year; i++)
	{
		if (isLeapYear(i))
			total += 366;
		else
			total += 365;
	}
	for (int i = 1; i < month; i++)
	{
		total += getNumberOfDaysInMonth(year, i);
	}
	return total;
}
int getNumberOfDaysInMonth(int year, int month)
{
	if (month == 1 || month == 3 || month == 5 || month == 7 ||
		month == 8 || month == 10 || month == 12)
		return 31;
	if (month == 4 || month == 6 || month == 9 || month == 11)
		return 30;
	
		if (month == 2) return isLeapYear(year) ? 29 : 28;
	
		 return 0;
}
bool  isLeapYear(int year)
{
	return year % 400 == 0 || (year % 4 == 0 && year % 100 != 0);
}