Python编程练习004：今天是一年中第几天

题目 输入某年某月某日，判断这一天是这一年的第几天？

程序分析：

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2时需考虑多加一天：
程序源代码：

year = int(raw_input('year:\n'))
month = int(raw_input('month:\n'))
day = int(raw_input('day:\n'))
 
months = (0,31,59,90,120,151,181,212,243,273,304,334)
if 0 < month <= 12:
    sum = months[month - 1]
else:
    print 'data error'
sum += day
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 'it is the %dth day.' % sum

输出结果：

year:
2015
month:
6
day:
7
it is the 158th day.

方法二：
def isLeapYear(y):
    return (y%400==0 or (y%4==0 and y%100!=0))
DofM=[0,31,28,31,30,31,30,31,31,30,31,30]
res=0
year=int(input('Year:'))
month=int(input('Month:'))
day=int(input('day:'))
if isLeapYear(year):
    DofM[2]+=1
for i in range(month):
    res+=DofM[i]
print(res+day)