Python3输入年月日算出这是一年的第几天。

from functools import reduce
year = int(input('year:\n'))
mOnth= int(input('month:\n'))
days = int(input('days:\n'))

mOnths= [0,31,28,31,30,31,30,31,31,30,31,30]
leap_moths = [0,31,29,31,30,31,30,31,31,30,31,30]

def de_leap(year):
    if (year % 400 == 0) or (year % 4 == 0) and (year % 100 != 0):
        return True
    else:
        return False

if de_leap(year):
    sum = reduce(lambda x,y:x+y,leap_moths[:month])+int(days)
    print("这是第%d天"%sum)

else:
    sum = reduce(lambda x, y: x + y, months[:month]) + int(days)
    print("这是第%d天" % sum)