#!/usr/bin/perl -w
push(@c,int(rand(5)))for(1..3);
sub ed{
    @o=split"",shift;
    ($d,$e)=@_;
    for(0..$#o){
        $k=$c[$_%@c];
        $e.=chr(ord($o[$_])+($d?$k:-$k));
    }
    return$e;
}

$message = "Hello, how are you?";
$encoded = ed("$message", 1);
$decoded = ed("$encoded", 0);

print "$message\n";
print "$encoded\n";
print "$decoded\n";