#!/usr/bin/perl -w
use strict;

#my $input = '[VP is [NP one NP] it [NP two NP] working VP]';
my $input = '[VP This stuff is [NP the left NP] [NP other thing NP] VP]';
#my $input = '[VP [NP This NP] [VP is [NP [NP the turning point NP] [PP to [NP the left NP] PP] NP] VP] . VP]';
#my $input = '[S [NP This NP] [VP is [NP [NP the turning point NP] ' . 
#        '[PP to [NP the left NP] PP] NP] VP] . S]';

$input =~ s/^\[\w+\s*(.*?)\s*\w+\]$/$1\n/;

my $bracket_count = 0;
my @output;
my $build_var;

foreach (split(//, $input)) {

        if (/\[/) {
                if ($bracket_count == 0) {#DR
                        $build_var =~ s/^\s*|\s*$//g;#dr
                        push @output, $build_var if ($build_var ne '');#DR
                        $build_var = '';#DR
                }#DR
                $bracket_count++;
                $build_var .= $_;#dr
        } elsif (/\]/) {
                $bracket_count--;
                $build_var .= $_;#dr
                if ($bracket_count == 0) {#DR
                        $build_var =~ s/^\s*|\s*$//g;#dr
                        push @output, $build_var if ($build_var ne '');#DR
                        $build_var = '';#DR
                }#DR
        } elsif (/\n/) {#dr Should be the end
                $build_var =~ s/^\s*|\s*$//g;#dr
                push @output, $build_var if ($build_var ne '');#DR
        } else {#dr
                $build_var .= $_;#dr
        }

}

foreach (@output) {
        print '"', $_, '"', "\n";
}