@Override
    public boolean remove(Object o) {
      if (!(o instanceof Map.Entry)) {
        return false;
      }

      @SuppressWarnings("unchecked")
      Map.Entry<K, V> e = (Map.Entry<K, V>)o;
      return LinkedCustomHashMap.this.remove(e.getKey()) != null;
    }
@Override
    public boolean remove(Object o)