1360_number_of_days_between_two_dates.py

class Solution:
    def daysBetweenDates(self, date1: str, date2: str) -> int:

        def parse_date(date: str) -> List[int]:
            num_str = date.split('-')
            ans = [int(s) for s in num_str]
            return ans
        
        def is_leap_year(year: int) -> bool:
            if (year % 4 == 0) and (year % 100 != 0):
                return True
            elif (year % 400 == 0):
                return True
            else:
                return False

        def cal_month_day(year: int) -> List[int]:
            if is_leap_year(year) == True:
                return [31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31]
            else:
                return [31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31]

        def cal_num_of_day(day: int, month: int, year: int) -> int:
            ans = 0
            for i in range(1971, year):
                if is_leap_year(i) == True:
                    ans += 366
                else:
                    ans += 365
            month_day = cal_month_day(year)
            ans += sum(month_day[:month-1]) + day
            return ans

        date_arr1 = parse_date(date1)
        date_arr2 = parse_date(date2)
        num_of_day1 = cal_num_of_day(date_arr1[2], date_arr1[1], date_arr1[0])
        num_of_day2 = cal_num_of_day(date_arr2[2], date_arr2[1], date_arr2[0])
        return abs(num_of_day1 - num_of_day2)

'''
    This is my personal record of solving Leetcode Problems. 
    If you have any questions, please discuss them in [Issues](https://github.com/mengxinayan/leetcode/issues).
    Copyright (C) 2020-2022  mengxinayan

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
'''