import java.util.Scanner;



public class PrintCalendar {

  /** Main method */

  public static void main(String[] args) {

    // Prompt the user to enter year
    Scanner scanner = new Scanner(System.in);



    // Prompt the user to enter year
    System.out.print("Enter full year (e.g., 2001): ");

    int year = scanner.nextInt();



    // Prompt the user to enter month
    System.out.print("Enter month in number between 1 and 12: ");

    int month = scanner.nextInt();



    // Print calendar for the month of the year
    printMonth(year, month);

  }



  /** Print the calendar for a month in a year */

  static void printMonth(int year, int month) {

    // Print the headings of the calendar
    printMonthTitle(year, month);



    // Print the body of the calendar
    printMonthBody(year, month);

  }



  /** Print the month title, e.g., May, 1999 */

  static void printMonthTitle(int year, int month) {

    System.out.println("         " + getMonthName(month)

      + " " + year);

    System.out.println("-----------------------------");

    System.out.println(" Sun Mon Tue Wed Thu Fri Sat");

  }



  /** Get the English name for the month */

  static String getMonthName(int month) {

    String monthName = null;

    switch (month) {

      case 1: monthName = "January"; break;

      case 2: monthName = "February"; break;

      case 3: monthName = "March"; break;

      case 4: monthName = "April"; break;

      case 5: monthName = "May"; break;

      case 6: monthName = "June"; break;

      case 7: monthName = "July"; break;

      case 8: monthName = "August"; break;

      case 9: monthName = "September"; break;

      case 10: monthName = "October"; break;

      case 11: monthName = "November"; break;

      case 12: monthName = "December";

    }



    return monthName;

  }



  /** Print month body */

  static void printMonthBody(int year, int month) {

    // Get start day of the week for the first date in the month
    int startDay = getStartDay(year, month);



    // Get number of days in the month
    int numberOfDaysInMonth = getNumberOfDaysInMonth(year, month);



    // Pad space before the first day of the month
    int i = 0;

    for (i = 0; i < startDay; i++)

      System.out.print("    ");



    for (i = 1; i <= numberOfDaysInMonth; i++) {

      if (i < 10)

        System.out.print("   " + i);

      else

        System.out.print("  " + i);



      if ((i + startDay) % 7 == 0)

        System.out.println();

    }



    System.out.println();

  }



  /** Get the start day of the first day in a month */

  static int getStartDay(int year, int month) {

    // Get total number of days since 1/1/1800
    int startDay1800 = 3;

    int totalNumberOfDays = getTotalNumberOfDays(year, month);



    // Return the start day
    return (totalNumberOfDays + startDay1800) % 7;

  }



  /** Get the total number of days since January 1, 1800 */

  static int getTotalNumberOfDays(int year, int month) {

    int total = 0;



    // Get the total days from 1800 to year - 1
    for (int i = 1800; i < year; i++)

    if (isLeapYear(i))

      total = total + 366;

    else

      total = total + 365;



    // Add days from Jan to the month prior to the calendar month
    for (int i = 1; i < month; i++)

      total = total + getNumberOfDaysInMonth(year, i);



    return total;

  }



  /** Get the number of days in a month */

  static 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; // If month is incorrect
  }



  /** Determine if it is a leap year */

  static boolean isLeapYear(int year) {

    return year % 400 == 0 || (year % 4 == 0 && year % 100 != 0);

  }

}