import java.util.TreeMap;
public class BaseLevelLearningEngine implements EngineInterface {
private BookmarkReader reader;
private final Map<String, Map<Integer, Double>> userMaps;
private final Map<String, Map<Integer, Double>> resMaps;
<BUG>private final Map<String, Double> topTags;
</BUG>
public BaseLevelLearningEngine() {
userMaps = new HashMap<>();
resMaps = new HashMap<>();

import java.util.TreeMap;
public class BaseLevelLearningEngine implements EngineInterface {
private BookmarkReader reader;
private final Map<String, Map<Integer, Double>> userMaps;
private final Map<String, Map<Integer, Double>> resMaps;
private final Map<Integer, Double> topTags;
public BaseLevelLearningEngine() {
userMaps = new HashMap<>();
resMaps = new HashMap<>();
