void RBTree :: RBdelete( NodePtr z )
{
NodePtr x ;
NodePtr y = z ;
char y_original_color = y->color ;
if(z->left == nil){
x = z->right;
RBTransplant(z, z->right);
}
else if(z->right == nil){
x = z->left;
RBTransplant(z, z->left);
}
else{
y = Tree_minimum(z->right);
y_original_color = y->color;
x = y->right;
if(y->p == z){
x->p = y;
}else{
RBTransplant(y, y->right);
y->right = z->right;
y->right->p = y;
}
RBTransplant(z,y);
y->left = z->left;
y->left->p = y;
y->color = z->color;
}
if ( y_original_color == 'B' )
deleteFixup( x ) ;
}
void RedBlackTree::RBDelete(RedBlackNode *pNode)
{
RedBlackNode *pPost = pNode;
RedBlackNode *pPostOrigin = nullptr;
NodeColor postOrigColor = pPost->m_nColor;
if (pNode->m_pLeft == m_pNull)
{
pPostOrigin = pNode->m_pRight;
RBTransplant(pNode, pNode->m_pRight);
}
else if (pNode->m_pRight == m_pNull)
{
pPostOrigin = pNode->m_pLeft;
RBTransplant(pNode, pNode->m_pLeft);
}
else
{
pPost = Mininum(pNode->m_pRight);
postOrigColor = pPost->m_nColor;
pPostOrigin = pPost->m_pRight;
if (pPost->m_pParent == pNode)
{
pPostOrigin->m_pParent = pPost;
}
else
{
RBTransplant(pPost, pPost->m_pRight);
pPost->m_pRight = pNode->m_pRight;
pPost->m_pRight->m_pParent = pPost;
}
RBTransplant(pNode, pPost);
pPost->m_pLeft = pNode->m_pLeft;
pPost->m_pLeft->m_pParent = pPost;
pPost->m_nColor = pNode->m_nColor;
}
if (postOrigColor == black)
{
RBDeleteFix(pPostOrigin);
}
}
void deleteFromRBTree(Tree *tree, Node *node)
{
if (node == tree->nil) return;
int node_original_color = node->color;
Node *changeNode = node;
Node *n = node;
while (n->parent != tree->nil)
{
n = n->parent;
n->size--;
}
if (node->left == tree->nil)
{
changeNode = node->right;
transplant(tree, node, node->right);
}
else if (node->right == tree->nil)
{
changeNode = node->left;
transplant(tree, node, node->left);
}
else
{
Tree t;
t.root = node->right;
t.nil = tree->nil;
Node *min = RBMinimum(&t);
Node *end = min->right;
node_original_color = min->color;
changeNode = end;
min->size = node->size - 1;
if (node == tree->root) tree->root = min;
if (node->right != min)
{
RBTransplant(tree, min, min->right);
min->right = node->right;
node->right->parent = min;
}
min->left = node->left;
node->left->parent = min;
RBTransplant(tree, node, min);
n = min->right;
while (n != end)
{
n->size--;
n = n->left;
}
min->color = node->color;
}
free(node);
if (node_original_color == BLACK)
{
RBDeleteFixup(tree, changeNode);
}
}
