Python教程-Python程序：查找两个给定日期之间的天数

在本教程中，我们将讨论如何编写Python程序来查找两个给定日期之间的天数。

假设我们有两个日期，我们的预期输出将是：

示例：

Input: Date_1 = 12/10/2021, Date_2 = 31/08/2022  
Output: Number of Days between the given Dates are: 323 days  
Input: Date_1 = 10/09/2023, Date_2 = 04/02/2025  
Output: Number of Days between the given Dates are: 323 days: 513 days  

方法1：朴素方法

在这种方法中，朴素的解决方案将从date_1开始，它将继续计算天数，直到达到date_2。这个解决方案需要超过O(1)次。它是计算日期之前的总天数的简单解决方案，这意味着它将计算从00/00/0000到date_1的总天数，然后将计算在date_2之前的总天数。最后，它将以给定日期之间的总天数的形式返回两个计数之间的差异。

示例：

# First, we will create a class for dates  
class date_n:  
    def __init__(self, day, month, year):  
        self.day = day  
        self.month = month  
        self.year = year  
   
   
# For storng number of days in all months from  
# January to December.  
month_Days = [31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31]  
   
# This function will count the number of leap years from 00/00/0000 to the #given date  
   
   
def count_Leap_Years(day):  
   
    years = day.year  
   
    # Now, it will check if the current year should be considered for the count          # of leap years or not.  
    if (day.month <= 2):  
        years -= 1  
   
    # The condition for an year is a leap year: if te year is a multiple of 4, and a            # multiple of 400 but not a multiple of 100.  
    return int(years / 4) - int(years / 100) + int(years / 400)  
   
   
# This function will return number of days between two given dates  
def get_difference(date_1, date_2):  
   
    # Now, it will count total number of days before first date "date_1"  
   
    # Then, it will initialize the count by using years and day  
    n_1 = date_1.year * 365 + date_1.day  
   
    # then, it will add days for months in the given date  
    for K in range(0, date_1.month - 1):  
        n_1 += month_Days[K]  
   
    # As every leap year is of 366 days, we will add   
    # a day for every leap year  
    n_1 += count_Leap_Years(date_1)  
   
    # SIMILARLY, it will count total number of days before second date "date_2"  
   
    n_2 = date_2.year * 365 + date_2.day  
    for K in range(0, date_2.month - 1):  
        n_2 += month_Days[K]  
    n_2 += count_Leap_Years(date_2)  
   
    # Then, it will return the difference between two counts  
    return (n_2 - n_1)  
   
   
# Driver program  
date_1 = date_n(12, 10, 2021)  
date_2 = date_n(30, 8, 2022)  
   
print ("Number of Days between the given Dates are: ", get_difference(date_1, date_2), "days")  

输出：

Number of Days between the given Dates are:  322 days

方法2：使用Python datetime模块

在这种方法中，我们将看到如何使用Python的内置函数“datetime”来解决各种日期时间相关的问题。要找到两个日期之间的差异，我们可以将两个日期以日期类型格式输入，然后将它们相减，结果将是两个给定日期之间的天数。

示例：

from datetime import date as date_n  
   
def number_of_days(date_1, date_2):  
    return (date_2 - date_1).days  
       
# Driver program  
date_1 = date_n(2023, 9, 10)  
date_2 = date_n(2025, 2, 4)  
print ("Number of Days between the given Dates are: ", number_of_days(date_1, date_2), "days")  

输出：

Number of Days between the given Dates are:  513 days

结论

在本教程中，我们讨论了如何编写Python代码来查找两个给定日期之间的总天数的两种不同方法。