class Doom {
    public static void main(String[] args) {
        final Date[] dates = {
            new Date(1800,1,6),
            new Date(1875,3,29),
            new Date(1915,12,7),
            new Date(1970,12,23),
            new Date(2043,5,14),
            new Date(2077,2,12),
            new Date(2101,4,2)
        };

        for (Date d : dates)
            System.out.println(
                String.format("%s: %s", d.format(), d.weekday()));
    }
}

class Date {
    private int year, month, day;

    private static final int[] leapdoom = {4,1,7,4,2,6,4,1,5,3,7,5};
    private static final int[] normdoom = {3,7,7,4,2,6,4,1,5,3,7,5};
    public static final String[] weekdays = {
        "Sunday", "Monday", "Tuesday", "Wednesday",
        "Thursday", "Friday", "Saturday"
    };

    public Date(int year, int month, int day) {
        this.year = year;
        this.month = month;
        this.day = day;
    }

    public boolean isLeapYear() {
        return year%4 == 0 && (year%100 != 0 || year%400 == 0);
    }

    public String format() {
        return String.format("%02d/%02d/%04d", month, day, year);
    }

    public String weekday() {
        final int c = year/100;
        final int r = year%100;
        final int s = r/12;
        final int t = r%12;

        final int c_anchor = (5 * (c%4) + 2) % 7;
        final int doom = (s + t + t/4 + c_anchor) % 7;
        final int anchor =
            isLeapYear() ? leapdoom[month-1] : normdoom[month-1];

        return weekdays[(doom + day - anchor + 7) % 7];
    }
}