public ArrayList<Pair<Double, Integer>> search(HashMap<String, String> query, int offset, int k, boolean binary){

        ArrayList<String> terms = this.preprocess(query);

        HashMap<Integer, Double> scores = new HashMap<Integer, Double>();

        HashMap<Integer, Integer> length = new HashMap<Integer, Integer>();

        for(String term : terms){

            double idf = Frequency.idf(this.index, term);

            double tfq = 1; // vai ter uma funcao aqui que pega a frequencia na query

            double wtq = tfq*idf;

            for(IntegerPair doc : this.index.get(term)){

                int id = doc.getId();

                int tfd = doc.getFrequency(); // == wtd

                if(!scores.containsKey(id)){
                    scores.put(id, 0.0);
                    length.put(id, 0);
                }

                length.put(id,  tfd*tfd);
                scores.put(id, scores.get(id) + wtq * tfd);

            }

            ArrayList<Pair<Double, Integer>> results = new ArrayList<Pair<Double, Integer>>();

            for(Integer id : scores.keySet()){
                double normalized = scores.get(id)/Math.sqrt(length.get(id));
                Pair<Double, Integer> p = new Pair<Double, Integer>(normalized,id);
                results.add(p);
            }

            Collections.sort(results);

            if(k < 0) return results;

            return (ArrayList<Pair<Double, Integer>>) results.subList(offset, offset+k);

        }