python计算当天是今年的第几天*

python计算当天是今年的第几天

import time

date = time.localtime()
year,month,day = date[:3]
day_month = [31,28,31,30,31,30,31,31,30,31,30,31]
if year%400 == 0 or (year%4==0 and year%100!=0):
    day_month[1] = 29
if month == 1:
    print(day)
else:
    print(sum(day_month[:month-1])+day)

sum(day_month[:n])
注意最后一行sum函数的应用，它可以将列表中的前n项元素求和。

103  # 今天是2020/4/12

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注意列表截取片段的应用

x = [9,8,7,6,5,4,3]
print(x[1:3])

得到的是第二项和第三项

[8, 7]

……………………………………………………………………………………
·
下面是第二种方法

def is_leap(year):   # 闰年的判断
    if (year%4==0 and year%100!=0) or year%400==0:
        return True
    else:
        return False

year = int(input('请输入年份：'))
month = int(input('请输入月份：'))
date = int(input('请输入日期：'))

def days_th(year,month,date): # 给定日期是当年的多少天
    days = [31,28,31,30,31,30,31,31,30,31,30,31]
    if is_leap(year):
        days[1]=29
        test = False
    if year>0:
        if month>0 and month<=12:
            if date>0 and date<=days[month-1]:
                test = True
    if test:
        answer = 0
        for i in range(month-1):  # 注意范围
            answer += days[i]
        answer += date
        return answer
    else:
        print('Your date is unreasonable, please enter again.')
print(days_th(year,month,date))

请输入年份：2020
请输入月份：4
请输入日期：12
103