python之菜鸟100例--005

题目：输入某年某月某日，判断这一天是这一年的第几天？

year = int(input("请输入年份："))
month = int(input("请输入月份："))
day = int(input("请输入日："))
months = [31,28,31,30,31,30,31,31,30,31,30,31]
sum = day
if (month > 13) or (month < 0):
    print("输入数据有误，请重新输入！")
if year%400==0 or(year%100!=0 and year%4==0):#判断当前是否是闰年
    for i in range(0,month-1):
        sum += months[i]
    print("今天是{}的第{}天".format(year,sum+1))
else:
    if month > 2:
        for i in range(0,month-1):
            sum += months[i]
    else:
        for i in range(0,month-1):
            sum += months[i]
    print("今天是{}的第{}天".format(year,sum))