Xref: utzoo comp.lang.c:17486 comp.lang.modula2:1404 comp.lang.pascal:1678
Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!cornell!rochester!rit!ritcv!dgr0093
From: dgr0093%ritcv@cs.rit.edu (340 Ok)
Newsgroups: comp.lang.c,comp.lang.modula2,comp.lang.pascal
Subject: Re: Another Silly programming puzzle....
Summary: Ah c'mon, it's easy to do better than THAT..
Keywords: contest silly
Message-ID: <1039@cs.rit.edu>
Date: 7 Apr 89 00:35:27 GMT
References: <1210@microsoft.UUCP> <12320@reed.UUCP>
Sender: news@cs.rit.edu
Reply-To: dgr0093%ritcv@cs.rit.edu (Michelangelo H. Jones)
Followup-To: comp.lang.c
Organization: Rochester Institute of Technology, Rochester, NY
Lines: 50

I wasn't going to post this, but decoding rot13 text is much easier than that
last program would indicate. I wrote this a few months ago, and it's a full
text filter, so you can pipe things at it as well as calling it with a 
filename to translate. I find the "text filter guts" very useful for building
other simple text filters.

Of course, "rot13 file | rot13" just types out the original file, so you can be
silly with it, too, if you're so inclined. :)

program rot13;

type
  line = string[120];

var
  buf: line;

  function rot13 (inp:line): line;

  var
    count: integer;

  begin
    for count := 1 to length(inp) do
      case inp[count] of
        'A'..'M', 'a'..'m': inp[count] := chr(ord(inp[count])+13);
        'N'..'Z', 'n'..'z': inp[count] := chr(ord(inp[count])-13)
      end;
    rot13 := inp
  end;

begin
  if paramcount > 0 then begin
    close (input);
    assign (input, paramstr(1));
    {$I-} reset (input); {$I+}
    if ioresult <> 0 then begin
      writeln ('Error opening ',paramstr(1), ' as input: aborting');
      halt
    end
  end;
  repeat
    readln (buf);
    writeln (rot13(buf))
  until eof (input)
end.

-------------------------------------------------------------------
  Dave Rutherford   Michelangelo H. Jones   DGR0093@RITVAX.BITNET
-------------------------------------------------------------------