SiroDiaz / DataStructures

     * @param DataStructures\Trees\Nodes\BSTNode $node the start point.

     * @return DataStructures\Trees\Nodes\BSTNode|null the minimum node.

     */

    private function getMinNode(BinaryNodeInterface $node = null) {

        if($node === null) {

            return null;

        }

        while($node->left !== null) {

            $node = $node->left;

        }

        return $node;

    }

    /**

     * Returns the maximum node from a given node in position X.

     * @param DataStructures\Trees\Nodes\BSTNode $node the start point.

     * @return DataStructures\Trees\Nodes\BSTNode|null the maximum node.

     */

    private function getMaxNode(BinaryNodeInterface $node = null) {

        if($node === null) {

            return null;

        }

        while($node->right !== null) {

            $node = $node->right;

        }

        return $node;

    }

    /**

     * Deletes the node with the minimum key and returns it. The most left and more bottom.