code: public V remove(final int key) {
  		IntLinkedEntry<V> entry = removeEntry(key);
  		if (entry == null) {
  			return null;
  		}
  		V ret = entry.value;
  		reuseAfterDelete(entry);
  
  		return ret;
  	}
docs: Removes the mapping with the specified key from this map.
  
  @param key the key of the mapping to remove.
  @return the value of the removed mapping or {@code null} if no mapping
  for the specified key was found.