#!/usr/bin/perl
#!/usr/bin/perl
use strict;
use warnings;
use 5.012;

# See 910956.pl (re playfair cipher) for salt, key and encoding -- # 
as a follow on, modify encoding with possibility of multiple 
# (i,e. "varying" or "inconsistent") insertions between dup letters

my @range = ("Q","V","X","Y","Z",);
my $seen = "";

my $message = uc(<>);
$message =~ s/[^A-Z0-9]//gi;				# remove punct, etc
$message =~ s/j/i/gi;
$message =~ s/q/O/gi;  					# replace [Qq] with [Oo]
$message =~ s/\s+//g;  					# remove spaces
$message .= "X" if length($message)%2==1; 	# make length an even value

my @char = split('', $message);

say "\n" . "-" x10 . "\n";

for my $char(@char) {
	if ($seen eq ($char)) {
		my $i = int(rand(4));
		my $letter = $range[$i];
		print $letter . $char;        # recode as push to encoded array for later printing
	} else {                              # as five char groups
		print ($char); 	}             # recode: ditto
	$seen = $char;
}

say "\n";