rotateLeft.c 1.33 KB
/**
 * \file
 *
 * \author	Georg Hopp
 *
 * \copyright
 * Copyright © 2012  Georg Hopp
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include "tr/tree.h"

void
TR_treeRotateLeft(TR_Tree * this, TR_Tree node)
{
	TR_Tree rightChild = TR_TREE_RIGHT(node);
	TR_Tree rcLeftSub  = TR_TREE_RIGHT_LEFT(node);

	rightChild->left   = node;
	rightChild->parent = TR_TREE_PARENT(node);
	node->right        = rcLeftSub;
	if (NULL != rcLeftSub) {
		rcLeftSub->parent  = node;
	}   

	if (NULL != TR_TREE_PARENT(node)) {
		if (TR_TREE_PARENT(node)->left == node) {
			TR_TREE_PARENT(node)->left = rightChild;
		} else {
			TR_TREE_PARENT(node)->right = rightChild;
		}   
	} else {
		*this = rightChild;
	}   

	node->parent = rightChild;
}

// vim: set ts=4 sw=4: