一个简单,优美的代码实现如下:

date = input().split(' ')
year = int(date[0])
month = int(date[1])
day = int(date[2])

day_list = [0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31]

if (year % 4 == 0 and year % 100 != 0) or (year % 400 == 0) :
    day_list[2] += 1    # 闰年

sum_day = 0
for i in range(month):
    sum_day += day_list[i]
sum_day += day

print(sum_day)