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[Stormalong]

[PUZZLE - SOLVED] New email "ACTIVITY REPORT 21-SE1&quo

[Nirvelli]

Would it be possible to post that script? Thanks if you can.

[bill]

While you're at it, any chance you could grace us with a short narrative on the substitution code you worked out? Is it an arbitrary substitution or Baudot or some other 5 bit alphabet?

[Stormalong]

Sure, here is the script. You'll need a system with perl to use it. Just run it with the encoded text (V's and W's) on the command line and the answer pops out the bottom. It also prints out the translation character by character because the translation table isn't quite complete, so you'll be able to spot any characters it misses.

As for the code, its a simple substitution cipher, where each unique group of 5 characters represents a letter. ie VWVWV = A
There doesn't seem to be a specific pattern to it, but I haven't analyzed it in detail.

#!/usr/bin/perl

$line = $ARGV[0];

$line =~ s/W/1/g;
$line =~ s/V/0/g;

$trans["1"] = "v";
$trans["2"] = "x";
$trans["3"] = "m";
$trans["5"] = "g";
$trans["6"] = "b";
$trans["7"] = "o";
$trans["8"] = "q";
$trans["9"] = "p";
$trans["10"] = "y";
$trans["11"] = "h";
$trans["12"] = "w";
$trans["13"] = "l";
$trans["14"] = "z";
$trans["15"] = "t";
$trans["17"] = "c";
$trans["18"] = "f";
$trans["19"] = "n";
$trans["20"] = "j";
$trans["21"] = "r";
$trans["22"] = "d";
$trans["24"] = "u";
$trans["25"] = "i";
$trans["26"] = "s";
$trans["28"] = "a";
$trans["30"] = "e";

while ($line ne "") {
$piece = substr($line, 0, 5, "");
$val = `echo "ibase=2; $piece" | bc`;
chop $val;
$c = substr($msg, $val-1, 1);
print "$trans[$val] $val\n";
$result .= $trans[$val];
}
print "$result\n";

[catherwood]

[Nirvelli]

Thanks Just what I needed.

[Grimakus]

"BC is not a recognised program"