@Override public int size() { assert size != 0 || root.isEmpty(); return size; }
@Override public int size() { assert size != 0 || root.isEmpty(); return size; }
@Override public int size() { assert size != 0 || root.isEmpty(); return size; }
@Override public int size() { assert size != 0 || root.isEmpty(); return size; }
@Override public int size() { assert size != 0 || root.isEmpty(); return size; }