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Re: King - Chapter 5 date.c

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flebber <flebber.crue@gmail.com> writes:
> On Dec 21, 10:13 am, Seebs <usenet-nos...@seebs.net> wrote:
[...]
>> You told the user to enter a *4-digit* year (good move) and now
>> you're going to discard the century entered and use 20?
>
> The book states that the 20%.2d has to be used as otherwise a year
> such as 2005 would be printed as 205.

I suspect you've misunderstood what the book says.

If the year value is a 2-digit year restricted to the years 2000-2099,
then printing it with "20%.2d" should work.  If you print it with
"20%d", it won't print a leading 0 for values less than 10, so a year
entered as 5 will print as "205" rather than the correct "2005".

In some contexts, it's common to represent as year as the number of
years since 1900 (this is how the tm_year member of struct tm, defined
in <time.h>, works).  If you were using that representation, you
wouldn't want to prepend either "19" or "20" to the year; you'd want to
add 1900 to it.

But as Seebs says, your prompt is:

       printf("Enter the date mm/dd/yyyy: ");

which asks for a 4-digit year.  The user is going to enter "2005", not
"05" or "5".

Perhaps the book intends the prompt to be:

       printf("Enter the date mm/dd/yy: ");

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
    Will write code for food.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"

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King - Chapter 5 date.c flebber <flebber.crue@gmail.com> - 2011-12-20 14:50 -0800
  Re: King - Chapter 5 date.c Seebs <usenet-nospam@seebs.net> - 2011-12-20 23:13 +0000
    Re: King - Chapter 5 date.c flebber <flebber.crue@gmail.com> - 2011-12-20 20:43 -0800
      Re: King - Chapter 5 date.c Geoff <geoff@invalid.invalid> - 2011-12-20 22:47 -0800
        Re: King - Chapter 5 date.c Seebs <usenet-nospam@seebs.net> - 2011-12-21 08:00 +0000
          Re: King - Chapter 5 date.c Geoff <geoff@invalid.invalid> - 2011-12-21 00:22 -0800
      Re: King - Chapter 5 date.c Keith Thompson <kst-u@mib.org> - 2011-12-21 03:55 -0800
      Re: King - Chapter 5 date.c James Kuyper <jameskuyper@verizon.net> - 2011-12-21 08:22 -0500
    Re: King - Chapter 5 date.c flebber <flebber.crue@gmail.com> - 2011-12-20 20:50 -0800
      Re: King - Chapter 5 date.c Geoff <geoff@invalid.invalid> - 2011-12-20 22:45 -0800
        Re: King - Chapter 5 date.c André Gillibert <MetaEntropy.removeThis@gmail.com> - 2011-12-21 11:35 +0100
          Re: King - Chapter 5 date.c Geoff <geoff@invalid.invalid> - 2011-12-21 03:57 -0800
          Re: King - Chapter 5 date.c Seebs <usenet-nospam@seebs.net> - 2011-12-21 19:12 +0000
          Re: King - Chapter 5 date.c "BartC" <bc@freeuk.com> - 2011-12-21 22:17 +0000
            Re: King - Chapter 5 date.c James Kuyper <jameskuyper@verizon.net> - 2011-12-21 18:07 -0500
        Re: King - Chapter 5 date.c superpollo <superpollo@tznvy.pbz> - 2011-12-21 14:44 +0100

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