/**
* Check wether there should be changes in the downward tree structure.
*
* @return boolean
*/
protected function hasChange()
{
return !($this->bound1() == $this->node->getRight() || $this->bound1() == $this->node->getLeft());
}
/**
* @param Node $node
* @param array $array
* @param Key $lo
* @param Key $hi
*/
private function _range(Node $node, array &$array, Key $lo, Key $hi)
{
if (!$node->getLength()) {
return;
}
$cmpLo = $node->getKey()->compare($lo);
$cmpHi = $node->getKey()->compare($hi);
if ($cmpLo > 0) {
$this->_range($node->getLeft(), $array, $lo, $hi);
}
if ($cmpLo >= 0 && $cmpHi <= 0) {
$array[] = $node;
}
if ($cmpHi < 0) {
$this->_range($node->getRight(), $array, $lo, $hi);
}
}
private function flipColors(Node $node)
{
$node->setColor(Node::RED);
$node->getLeft()->setColor(Node::BLACK);
$node->getRight()->setColor(Node::BLACK);
}
