sub step {
    my ($dir, $r, $c) = @_;
    if ($dir == N)     {return (--$r, $c)}
    elsif ($dir == NE) {return (--$r, ++$c)}
    elsif ($dir == E)  {return ($r, ++$c)}
    elsif ($dir == SE) {return (++$r, ++$c)}
    elsif ($dir == S)  {return (++$r, $c)}
    elsif ($dir == SW) {return (++$r, --$c)}
    elsif ($dir == W)  {return ($r, --$c)}
    elsif ($dir == NW) {return (--$r, --$c)}
    else {
        die "Inside 'step': invalid param\n"
    }
}

##</code><code>##

our %step = ( N  => { R => -1, C =>  0 },
              NE => { R => -1, C => +1 },
              E  => { R =>  0, C => +1 },
              SE => { R => +1, C => +1 },
              S  => { R => +1, C =>  0 },
              SW => { R => +1, C => -1 },
              W  => { R =>  0, C => -1 },
              NW => { R => -1, C => -1 } 
            );

##</code><code>##

($rows, $cols) = step($dir, $rows, $cols);

##</code><code>##

$rows += $step{$dir}{R};
$cols += $step{$dir}{C};

##</code><code>##

$rows -= $step{$dir}{R};
$cols -= $step{$dir}{C};

##</code><code>##

for my $idx (0..$#words)