void RBTreeDelete(RBTree_t *tree, struct RBNode_t *node)
{
struct RBNode_t *y = node;
struct RBNode_t *x;
RBColor_t origincolor = y->mColor;
if(node->mLeft == &tree->mSentinelLeaf) {
x = node->mRight;
RBTreeTransplant(tree, node, node->mRight);
} else if(node->mRight == &tree->mSentinelLeaf) {
x = node->mLeft;
RBTreeTransplant(tree, node, node->mLeft);
} else {
y = RBTreeMinimum(node->mRight, &tree->mSentinelLeaf);
origincolor = y->mColor;
x = y->mRight;
if(y->mParent == node) {
x->mParent = y;
} else {
RBTreeTransplant(tree, y, y->mRight);
y->mRight = node->mRight;
y->mRight->mParent = y;
}
RBTreeTransplant(tree, node, y);
y->mLeft = node->mLeft;
y->mLeft->mParent = y;
y->mColor = node->mColor;
}
if(origincolor == RB_BLACK) {
RBTreeDeleteFixup(tree, x);
}
}
/*
z is deleted node;
y is the node which position on the tree will be replaced(Note that y not must be z);
x is the node that replacing y's position on the tree;
*/
void RBTreeDelete(struct rb_tree *rb, rb_key_t key) {
struct rb_node *x, *y, *z;
int yOriginColor;
z = RBTreeSearch(rb, key);
if (z == rb->nil) return ;
rb->size--;
y = z;
yOriginColor = y->color;
if (z->left == rb->nil) {
x = z->right;
RBTreeTransplant(rb, z, z->right);
} else if (z->right == rb->nil) {
x = z->left;
RBTreeTransplant(rb, z, z->left);
} else {
y = RBTreeMin(rb, z->right);
yOriginColor = y->color;
x = y->right;
if (y->p != z) {
RBTreeTransplant(rb, y, y->right);
y->right = z->right;
y->right->p = y;
}
RBTreeTransplant(rb, z, y);
y->left = z->left;
y->left->p = y;
y->color = z->color;
}
if (yOriginColor == BLACK && x != rb->nil)
RBTreeDeleteFixup(rb, x);
free(z);
}
