public void Delete(int key)
{
//if (key == null)
// throw new ArgumentNullException(nameof(key));
BinTreeNode <int> current = root;
while (current != null)
{
if (key.CompareTo(current.Data) == 0)
{
BinTreeNode <int> node = current;
if (current.Lchild != null)
{
node = GetMaxNode(current.Lchild);
}
else if (current.Rchild != null)
{
node = GetMinNode(current.Rchild);
}
current.Data = node.Data;
Remove(node);
Length--;
}
else if (key.CompareTo(current.Data) < 0)
{
current = current.Lchild;
}
else
{
current = current.Rchild;
}
}
}
private BinTreeNode <int> BalanceLeftRotate(BinTreeNode <int> current)
{
BinTreeNode <int> child = current.Rchild;
if (child.Bf > 0)
{
BinTreeNode <int> grand = child.Lchild;
RightRotate(grand, child);
if (grand.Bf < 0)
{
grand.Bf = -2;
child.Bf = 0;
}
else
{
int temp = grand.Bf;
grand.Bf = -1 * child.Bf;
child.Bf = -1 * temp;
}
child = grand;
}
LeftRotate(child, current);
current.Bf = -1 * child.Bf - 1;
child.Bf = child.Bf < -1 ? 0 : child.Bf + 1;
return(child);
}
private void AdjustRemove(BinTreeNode <int> node)
{
if (node.Bf > 1)
{
node = BalanceRightRotate(node);
}
else if (node.Bf < -1)
{
node = BalanceLeftRotate(node);
}
BinTreeNode <int> parent = node.Parent;
if (node.Bf == 0 && parent != null)
{
if (node == parent.Lchild)
{
parent.Bf--;
}
else
{
parent.Bf++;
}
if (parent.Bf != 1 && parent.Bf != -1)
{
AdjustRemove(parent);
}
}
}
private SolidBrush drawBrush = new SolidBrush(Color.Black); //写字符串用的刷子
public void Insert(int key)
{
//if (key == null) throw new ArgumentException(nameof(key));
if (root == null)
{
root = new BinTreeNode <int>(key);
return;
}
BinTreeNode <int> current = new BinTreeNode <int>(key);
FindPosition(root, current);
BinTreeNode <int> parent = current.Parent;
if (parent != null)
{
Length++;
//如果新插入的节点是做孩子 父亲节点平衡因子+1
//如果新插入的节点是右孩子 父亲节点平衡因子-1
if (current == parent.Lchild)
{
parent.Bf++;
}
else
{
parent.Bf--;
}
if (parent.Bf != 0)
{
AdjustInsert(parent);
}
}
}
private BinTreeNode <T> FindParent(BinTreeNode <T> current, BinTreeNode <T> find)
{
if (find == null)
{
throw new Exception("传入参数find为空");
}
if (current == null)
{
return(null);
}
if (current.Lchild != null && current.Lchild.Equals(find) == true)
{
return(current);
}
if (current.Rchild != null && current.Rchild.Equals(find) == true)
{
return(current);
}
BinTreeNode <T> temp = FindParent(current.Lchild, find);
if (temp != null)
{
return(temp);
}
else
{
return(FindParent(current.Rchild, find));
}
}
private void AdjustInsert(BinTreeNode <int> node)
{
if (node.Bf > 1)
{
BalanceRightRotate(node);
}
else if (node.Bf < -1)
{
BalanceLeftRotate(node);
}
else
{
BinTreeNode <int> root = node.Parent;
if (root != null)
{
if (node == root.Lchild)
{
root.Bf++;
}
else
{
root.Bf--;
}
if (root.Bf != 0)
{
AdjustInsert(root);
}
}
}
}
//private void draw(PaintEventArgs e,Graphics dc,BinTreeNode<int> node,int x,int y)
//{
// if (node == null)
// {
// throw new Exception("空字符串");
// }
// dc.DrawEllipse(blackPen, x, y, 25, 20);
// String drawString = node.Data.ToString();//要显示的字符串
// PointF drawPoint = new PointF(x+1, y+3);//显示的字符串左上角的坐标
// e.Graphics.DrawString(drawString, drawFont, drawBrush, drawPoint);
// delt /= 2;
// if (node.Lchild != null)
// draw(e, dc, node.Lchild, delt, y + 40);
// if (node.Rchild != null)
// draw(e, dc, node.Rchild, x + delt, y + 40);
//}
private void draw(Graphics dc, BinTreeNode <int> node, int x, int y, int delt_f)
{
if (node == null)
{
return;
}
dc.DrawEllipse(blackPen, x, y, 25, 20);
String drawString = node.Data.ToString(); //要显示的字符串
PointF drawPoint = new PointF(x + 1, y + 3); //显示的字符串左上角的坐标
dc.DrawString(drawString, drawFont, drawBrush, drawPoint);
// delt /= 2;
if (node.Parent != null)
{
dc.DrawLine(blackPen, x + 10, y, delt_f + 10, y - 20);
}
if (node.Lchild != null)
{
draw(dc, node.Lchild, x - System.Math.Abs(x - delt_f) / 2, y + 40, x);
}
if (node.Rchild != null)
{
draw(dc, node.Rchild, x + System.Math.Abs(x - delt_f) / 2, y + 40, x);
}
}
private void Remove(BinTreeNode <int> node)
{
if (node == root)
{
root = null;
return;
}
BinTreeNode <int> parent = node.Parent;
if (node == parent.Lchild)
{
parent.Lchild = node.Lchild;
if (node.Lchild != null)
{
node.Lchild.Parent = parent;
}
parent.Bf--;
}
else
{
//parent.Rchild = null;
parent.Rchild = node.Lchild;
if (node.Lchild != null)
{
node.Lchild.Parent = parent;
}
parent.Bf++;
}
if (parent.Bf != 1 && parent.Bf != -1)
{
AdjustRemove(parent);
}
}
//寻找node节点的父亲节点
public void FindPosition(BinTreeNode <int> current, BinTreeNode <int> node)
{
if (node.Data < current.Data)
{
if (current.Lchild == null)
{
current.Lchild = node;
node.Parent = current;
}
else
{
FindPosition(current.Lchild, node);
}
}
else if (node.Data > current.Data)
{
if (current.Rchild == null)
{
current.Rchild = node;
node.Parent = current;
}
else
{
FindPosition(current.Rchild, node);
}
}
else
{
current.Data = node.Data;
}
}
private BinTreeNode <int> GetMinNode(BinTreeNode <int> current)
{
if (current.Lchild == null)
{
return(current);
}
return(GetMinNode(current.Lchild));
}
public BinTreeNode <T> GetParent(BinTreeNode <T> find)
{
if (find == null)
{
throw new Exception("传入参数find为null");
}
return(FindParent(root, find));
}
private void PostOrder(BinTreeNode <T> current)
{
if (current == null)
{
return;
}
PostOrder(current.Lchild);
orderString += current.Data.ToString() + " ";
PostOrder(current.Rchild);
}
private void LeftRotate(BinTreeNode <int> node, BinTreeNode <int> parent)
{
OperateForBothRotate(node, parent);
parent.Rchild = node.Lchild;
if (node.Lchild != null)
{
node.Lchild.Parent = parent;
}
node.Lchild = parent;
}
//private BinTree<int> binTree;
//public AVLTree(int data)
//{
// BinTreeNode<int> root = new BinTreeNode<int>();
// root.Data = data;
// binTree = new BinTree<int>(root);
//}
////右旋处理
//public void RRotate(BinTreeNode<int> P)
//{
// BinTreeNode<int> L;
// L = P.Lchild;
// P.Lchild = L.Rchild;
// L.Rchild = P;
// P = L;
//}
////左旋处理
//public void LRotate(BinTreeNode<int> P)
//{
// BinTreeNode<int> L;
// L = P.Rchild;
// P.Rchild = L.Lchild;
// L.Lchild = P;
// P = L;
//}
//public void LeftBalance(BinTreeNode<int> T)
//{
// BinTreeNode<int> L, Lr;
// L = T.Lchild; //L指向T左子树根节点
// switch (L.Bf)
// {
// case 1:
// T.Bf = L.Bf = 0;
// RRotate(T);
// break;
// case -1:
// Lr = L.Rchild;
// switch (Lr.Bf)
// {
// case 1:
// T.Bf = -1;
// L.Bf = 0;
// break;
// case 0:
// T.Bf = L.Bf = 0;
// break;
// case -1:
// T.Bf = 0;
// L.Bf = 1;
// break;
// }
// Lr.Bf = 0;
// LRotate(T.Lchild);
// RRotate(T);
// break;
// }
//}
private void MidOrder(BinTreeNode <int> current)
{
if (current == null)
{
return;
}
MidOrder(current.Lchild);
orderString += current.Data.ToString() + " ";
MidOrder(current.Rchild);
}
private int GetValue(BinTreeNode <int> current, int key)
{
if (current == null)
{
throw new Exception("节点为空");
}
if (current.Data > key)
{
return(GetValue(current.Lchild, key));
}
if (current.Data < key)
{
return(GetValue(current.Rchild, key));
}
return(current.Data);
}
private void OperateForBothRotate(BinTreeNode <int> node, BinTreeNode <int> parent)
{
BinTreeNode <int> grand = parent.Parent;
node.Parent = grand;
parent.Parent = node;
if (grand == null)
{
root = node;
}
else if (parent == grand.Rchild)
{
grand.Rchild = node;
}
else
{
grand.Lchild = node;
}
}
public string LevelTraversal()
{
orderString = string.Empty;
if (root != null)
{
Queue <BinTreeNode <T> > LQ = new Queue <BinTreeNode <T> >();
LQ.Enqueue(root);
while (LQ.Count == 0)
{
BinTreeNode <T> temp = LQ.Dequeue();
orderString += temp.Data.ToString() + " ";
if (temp.Lchild != null)
{
LQ.Enqueue(temp.Lchild);
}
if (temp.Rchild != null)
{
LQ.Enqueue(temp.Rchild);
}
}
}
return(orderString.Trim());
}
public BinTreeNode(T key)
{
this.data = key;
this.rchild = this.lchild = null;
this.bf = 0;
}
public BinTree(BinTreeNode <T> root)
{
this.root = root;
}