#! /usr/bin/perl

use 5.010;
use strict;
use warnings;
use File::Find;

my $dir = $ARGV[0] // q{.};

sub deepest {
  return if not -d;
  state $prev_dir = '';
  say if index $prev_dir, $_;
  $prev_dir = $_;
}

find(
  { wanted   => \&deepest,
    no_chdir => 1,
    bydepth  => 1,
  },
  $dir
);