import java.util.*;

public class MultisetUtils<E extends Number> extends Multiset<E>{
    public MultisetUtils() {
        super();
    }

    public E getSmallestElement() {
        PriorityQueue<E> smallestElementQueue = new PriorityQueue<>(super.values.keySet());
        return smallestElementQueue.peek();
    }

    public E getLargestElement() {
        PriorityQueue<E> largestElementQueue = new PriorityQueue<>(super.values.size(), Collections.reverseOrder());
        super.values.forEach((key, value) -> largestElementQueue.offer(key));
        return largestElementQueue.peek();
    }

    public E getSmallestWeightedElement() {
        double smallestWeightValue = 0;
        E smallestWeightElement = null;
        boolean check = true;
        for (Map.Entry<E, Integer> entry : super.values.entrySet()) {
            if (check) {
                smallestWeightElement = entry.getKey();
                smallestWeightValue = entry.getKey().doubleValue() * entry.getValue();
                check = false;
            } else if ((entry.getKey().doubleValue() * entry.getValue()) < smallestWeightValue) {
                smallestWeightValue = entry.getKey().doubleValue() * entry.getValue();
                smallestWeightElement = entry.getKey();
            }
        }
        return smallestWeightElement;
    }

    public E getLargestWeightedElement() {
        double largestWeightValue = 0;
        E largestWeightElement = null;
        boolean check = true;
        for (Map.Entry<E, Integer> entry : super.values.entrySet()) {
            if (check) {
                largestWeightElement = entry.getKey();
                largestWeightValue = entry.getKey().doubleValue() * entry.getValue();
                check = false;
            } else if ((entry.getKey().doubleValue() * entry.getValue()) > largestWeightValue) {
                largestWeightValue = entry.getKey().doubleValue() * entry.getValue();
                largestWeightElement = entry.getKey();
            }
        }
        return largestWeightElement;
    }

    public double sumElements() {
        double sumResult = 0;
        for (Map.Entry<E, Integer> entry : super.values.entrySet()) {
            sumResult += entry.getKey().doubleValue();
        }
        return sumResult;
    }

    public double weightedSum() {
        double weightedSumResult = 0;
        for (Map.Entry<E, Integer> entry : super.values.entrySet()) {
            weightedSumResult += entry.getKey().doubleValue() * entry.getValue();
        }
        return weightedSumResult;
    }

    public Multiset<E> concatSets(Multiset<E> set) {
        this.addAll(set);
        return this;
    }

    public List<E> sort() {
        Set<E> myTreeSet = new TreeSet<>(super.values.keySet());
        return new ArrayList<>(myTreeSet);
    }
}