Python输入某年某月某日,判断这一天是这一年的第几天并输出结果

以下是两种Python判断某年某月某日是这一年的第几天的例子：

1.将每月的天数进行相加，就可得到结果

year = int(input('请输入年份:'))
month = int(input('请输入月份:'))
day = int(input('请输入日期:'))
mouths = [0,31,28,31,30,31,30,31,31,30,31,30,31]
if year % 400 == 0 or year % 4 == 0:
    mouths[2] = 29
if 0 < month <= 12:
    days = 0
    for item in range(month):
        sum = mouths[item]
        days = days + sum
    day_s = days + day
    print(f'今天是今年的第{day_s}天')
else:
    print('输入日期超出范围')

2.以3月5日为例，应该先把前两个月的加起来，然后再加上5天即本年的第几天，特殊情况，闰年且输入月份大于3时需考虑多加一天

year = int(input('请输入年份:'))
month = int(input('请输入月份:'))
day = int(input('请输入日期:'))
months = (0,31,59,90,120,151,181,212,243,273,304,334)
if 0 <= month <= 12:
    sum = months[month -1]
    sum += day
else:
    print ('您输入的日期超出范围！！')
leap = 0
if (year % 400 == 0) or ((year %4==0) and (year % 100 !=0)):
    leap=1
if (leap == 1) and (month > 2):
    sum += 1
print ('今天是今年的第%s天.' % sum)