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Re: counted characters in strings

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On 10/06/2022 03:21, Robin Vowels wrote:
> Nevertheless, counting the number of characters was a constant source
> of error. It was easy enough to include the letter 'H' in the
> character count, sp that the following character became gobbled up in
> the Hollerith constant, and resulting in weird error messages. When a
> Hollerith constant was long enough to require a continuation card, it
> was even easier to lose count; the continuation character in column
> 6 sometimes being included. And when the Hollerith constant required
> 133 characters, how many coud reliably count all of them?

The point about coding forms was that each column of characters
was numbered, so you just had to take the first column and the last
and compute last - first + 1 to get the number of characters
in the string. You don't have to count each one individually.
If there is a continuation then you just compute last + 66 - first + 1
For 133 characters, there would be two continuation cards
and the last column would be the same as the first:
so quite easy to count reliably in fact!

Back in the days before pocket calculators, many people could
do simple arithmetic sums in their heads! :-)

--
			Martin

Dr Martin Ward | Email: martin@gkc.org.uk | http://www.gkc.org.uk
G.K.Chesterton site: http://www.gkc.org.uk/gkc | Erdos number: 4

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State-of-the-art algorithms for lexical analysis? Roger L Costello <costello@mitre.org> - 2022-06-05 20:53 +0000
  Re: State-of-the-art algorithms for lexical analysis? gah4 <gah4@u.washington.edu> - 2022-06-05 16:05 -0700
    Re: State-of-the-art algorithms for lexical analysis? Hans-Peter Diettrich <DrDiettrich1@netscape.net> - 2022-06-06 08:59 +0200
      State-of-the-art algorithms for lexical analysis? Christopher F Clark <christopher.f.clark@compiler-resources.com> - 2022-06-06 21:16 +0300
        Re: State-of-the-art algorithms for lexical analysis? Hans-Peter Diettrich <DrDiettrich1@netscape.net> - 2022-06-07 06:52 +0200
          Re: State-of-the-art algorithms for lexical analysis? Christopher F Clark <christopher.f.clark@compiler-resources.com> - 2022-06-07 19:40 +0300
            Re: State-of-the-art algorithms for lexical analysis? Hans-Peter Diettrich <DrDiettrich1@netscape.net> - 2022-06-08 05:32 +0200
              Re: counted strings, was State-of-the-art algorithms for lexical analysis? gah4 <gah4@u.washington.edu> - 2022-06-09 11:54 -0700
                Re: counted characters in strings "Robin Vowels" <robin51@dodo.com.au> - 2022-06-10 12:21 +1000
                Re: counted characters in strings Martin Ward <martin@gkc.org.uk> - 2022-06-11 10:52 +0100
                Re: counted characters in strings drb@msu.edu (Dennis Boone) - 2022-06-11 11:09 -0500
    Re: State-of-the-art algorithms for lexical analysis? Kaz Kylheku <480-992-1380@kylheku.com> - 2022-06-06 16:00 +0000
    References for PSL ? Christopher F Clark <christopher.f.clark@compiler-resources.com> - 2022-06-06 20:11 +0300

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