void add(@NotNull T element) {
    int prevOccurrences = myOccurrenceMap.addTo(element, 1);
    if (myBest == null) {
      myBestOccurrences = 1;
      myBest = element;
    }
    else if (myBest.equals(element)) {
      myBestOccurrences++;
    }
    else {
      myBestOccurrences = prevOccurrences + 1;
      myBest = element;
    }
  }
void add(@NotNull T element)