#!/usr/bin/perl -w
use strict;
use HTML::TokeParser::Simple;

my $total = 0;
my $p = HTML::TokeParser::Simple->new(*DATA);

my $length_left = shift || 40;
my $abstract = "";

while (my $t = $p->get_token) { 
	$_ = $t->as_is;

	if ($t->is_text) {
		s/\s+/ /g;
		s/^(.{1,$length_left}\S*).*/$1/s;
		$length_left -= length;
	}

	$abstract .= $_;

	last unless $length_left > 0;
}

print $abstract, $/;