CF304B.Calendar

Calendars in widespread use today include the Gregorian calendar, which is the de facto international standard, and is used almost everywhere in the world for civil purposes. The Gregorian reform modified the Julian calendar's scheme of leap years as follows:

Every year that is exactly divisible by four is a leap year, except for years that are exactly divisible by 100; the centurial years that are exactly divisible by 400 are still leap years. For example, the year 1900 is not a leap year; the year 2000 is a leap year.

In this problem, you have been given two dates and your task is to calculate how many days are between them. Note, that leap years have unusual number of days in February.

Look at the sample to understand what borders are included in the aswer.

当今广泛使用的日历包括公历（格里高利历），它是事实上的国际标准，几乎在全世界所有地区都用于民用目的。公历改革对儒略历的闰年规则作了如下修改：

• 凡能被 4 整除的年份为闰年，但能被 100 整除的世纪年份除外；然而，能被 400 整除的世纪年份仍为闰年。例如，1900 年不是闰年；2000 年是闰年。

本题中，你将获得两个日期，任务是计算它们之间相隔的天数。注意：闰年的 2 月天数异常。

请参考样例以明确答案所包含的边界。

The first two lines contain two dates, each date is in the format yyyy:mm:dd (1900 ≤ yyyy ≤ 2038 and yyyy:mm:dd is a legal date).

前两行包含两个日期，每个日期的格式均为 yyyy:mm:dd（其中 $1900 ≤ \text{yyyy} ≤ 2038$，且 yyyy:mm:dd 是一个合法的日期）。

Print a single integer — the answer to the problem.

输出一个整数——该问题的答案。