def age(day1, month1, year1, day2, month2, year2):
    e = year2 - year1
    if month2 < month1 or (month2 == month1 and day2 < day1):
        e -= 1
    return e

def complete_year(year, century):
    return (century - 1)*100 + year

def age_21(day1, month1, year1, day2, month2, year2):
    if 0 <= year1 <= 99:
        year1 = complete_year(year1, 21)
    if 0 <= year2 <= 99:
        year2 = complete_year(year2, 21)
    return age(day1, month1, year1, day2, month2, year2)

def compare_dates(day1, month1, year1, day2, month2, year2):
    if year1 < year2:
        r = -1
    elif year1 == year2:
        if month1 < month2:
            r = -1
        elif month1 == month2:
            if day1 < day2:
                r = -1
            elif day1 == day2:
                r = 0
            else:
                r = 1
        else:
            r = 1
    else:
        r = 1
    return r

def previous_date(day1, month1, year1, day2, month2, year2):
    return compare_dates(day1, month1, year1, day2, month2, year2) < 0

def same_date(day1, month1, year1, day2, month2, year2):
    return compare_dates(day1, month1, year1, day2, month2, year2) == 0

def later_date(day1, month1, year1, day2, month2, year2):
    return compare_dates(day1, month1, year1, day2, month2, year2) > 0