AoC 2023 day 18, part 2 (Perl)

#!/usr/bin/perl

use strict;
use warnings;

use feature         qw(say);

use Math::Vector::Real;
my ($Y,$X) = Math::Vector::Real->canonical_base(2);
my @Dirs = ($X, $Y, -$X, -$Y);

my $pos = V(0,0);
my @vertices = ($pos);
my $trench = 0;

while (<>) {
    my ($col) = m#[UDLR] \d+ (.*)#g;
    my ($len, $dir) = ($col =~ m#([[:xdigit:]]{5})(\d)#g);

    $len = oct("0x$len");

    $trench += $len;
    push( @vertices, $pos += $len * $Dirs[$dir] );
}

# Shoelace for area (loop gives twice the area (sign +'ve widdershins, -'ve for deasil))
my $area = 0;
foreach my $i (0 .. $#vertices - 1) {
    $area += $vertices[$i][0] * $vertices[$i+1][1];
    $area -= $vertices[$i][1] * $vertices[$i+1][0];
}

# Pick's formula: I+B = A + B/2 + 1 (but still needed to halve the Area from shoelace)
say "Part 2: ", (abs($area) + $trench) / 2 + 1;