Time and date calculation code in asp.net C

[Topic description] There are two dates, and the number of days between the two dates is calculated. If the two dates are consecutive, we set the number of days between them to two days. [input] There are multiple groups of data, each data set has two rows, representing two dates in the form of YYYYMMDD.

[Output] Output a row of data in each group, that is, the date difference.

[Example input] 2011041220110422

[Sample output] 11

A very simple question. The idea is very simple. Calculate the number of days between the two dates respectively to the one-year month, January 1, and then subtract and add one. The number of days between calculation and 00010101 contains the following common date calculation contents.

Leap year judgment Expression

According to the Gregorian calendar: the second day of the year, the second day of the year, but the four-year leap surplus, only 23 hours 15 minutes 4 seconds, a day, not too much, more than 44 minutes 56 seconds, accumulated to 25 minutes, 17 hours, 58 minutes, 24 seconds, about 3/4 of a day, so every hundred years of waste a year, to 400th years without waste.

The expression used to judge a leap year is as follows (in C)

The Code is as follows:	Copy code
! (Y % 400) | (! (Y % 4) & y % 100 ))   Or Y % 4? 0 :( y % 100? 1 :( y % 400? ))

Number of days from January 1, January 1

First, use the number of days in the first few months of the array index, and add the number of days in the current month. If it is a month greater than 3 and a leap year (pay attention to the judgment order, use | short circuit), add one day, then, the total number of days in the previous year is added. Here, the formula r + = -- y * 365 + y/4-y/100 + y/400 is used for calculation.

The Code is as follows:	Copy code
Int R [] = {120,151,181,212,243,273,304,334 }; Int calc (int y ){ Int m = y % 10000/100; Int r = M-1] + y % 100; Y/= 10000; R + = (m> 2 &&(! (Y % 400) | (! (Y % 4) & amp; y % 100 )))? 1:0; R + = -- y * 365 + y/4-y/100 + y/400; Return r; }

The original program code is as follows:

The Code is as follows:	Copy code
# Include <stdio. h> Int R [] = {120,151,181,212,243,273,304,334 }; Int calc (int y ){ Int m = y % 10000/100; Int r = M-1] + y % 100; Y/= 10000; R + = (m> 2 &&(! (Y % 400) | (! (Y % 4) & amp; y % 100 )))? 1:0; Return r + -- y * 365 + y/4-y/100 + y/400; } Int main (){ Int x, y; While (scanf ("% d", & x, & y )! = EOF) printf ("% dn", calc (y)-calc (x) + 1 ); }