rem: leftRotate(tree, node->parent);
add: rightRotate(tree, node->parent);
context: static void rbDeleteFixup(W_TreeBag *tree, W_Node *node){    W_Node *w;        while (node != tree->root && node->color == 'B') {	if (IS_LEFT(node)) {	    w = node->parent->right;	    if (w->color == 'R') {		w->color = 'B';		node->parent->color = 'R';		leftRotate(tree, node->parent);		w = node->parent->right;	    }	    if (w->left->color == 'B' && w->right->color == 'B') {		w->color = 'R';		node = node->parent;	    } else {		if (w->right->color == 'B') {		    w->left->color = 'B';		    w->color = 'R';		    rightRotate(tree, w);		    w = node->parent->right;		}		w->color = node->parent->color;		node->parent->color = 'B';		w->right->color = 'B';		leftRotate(tree, node->parent);		node = tree->root;	    }	} else {	    w = node->parent->left;	    if (w->color == 'R') {		w->color = 'B';		node->parent->color = 'R';		leftRotate(tree, node->parent);		w = node->parent->left;	    }	    if (w->left->color == 'B' && w->right->color == 'B') {		w->color = 'R';		node = node->parent;	    } else {		if (w->left->color == 'B') {		    w->right->color = 'B';		    w->color = 'R';		    rightRotate(tree, w);		    w = node->parent->left;		}		w->color = node->parent->color;		node->parent->color = 'B';		w->left->color = 'B';		leftRotate(tree, node->parent);		node = tree->root;	    }	    	}    }    node->color = 'B';}