public ZBinaryTreeNode <T> Find(T data)
{
ZBinaryTreeNode <T> node = null;
ZBinaryTreeNode <T> current = Root;
while (current != null)
{
int compareResult = current.Value.CompareTo(data);
if (compareResult == 0)
{
return(current);
}
else if (compareResult < 0)
{
current = current.LeftNode;
}
else
{
current = current.RightNode;
}
}
return(node);
}
private static ZBinaryTreeNode <T> BuildTree(List <T> preorderList, List <T> inorderList, int start, int end, int preIndex)
{
if (start > end)
{
return(null);
}
//Pick current node from preorder traversal using preIndex and increment preIndex
ZBinaryTreeNode <T> node = new ZBinaryTreeNode <T>(preorderList[preIndex++]);
//If this node has no children then return
if (start == end)
{
return(node);
}
//Else find the index of this node in inorder traversal
int inIndex = Search(inorderList, start, end, node.Value);
//Using index in inorder traversal, construct left and right subtrees
node.LeftNode = BuildTree(inorderList, preorderList, start, inIndex - 1, preIndex);
node.RightNode = BuildTree(inorderList, preorderList, inIndex + 1, end, preIndex);
return(node);
}
public List <T> LevelOrderList()
{
List <T> items = new List <T>();
ZQueue <ZBinaryTreeNode <T> > que = new ZQueue <ZBinaryTreeNode <T> >();
if (Root != null)
{
items.Add(Root.Value);
if (Root.LeftNode != null)
{
que.Enqueue(Root.LeftNode);
}
if (Root.RightNode != null)
{
que.Enqueue(Root.RightNode);
}
}
while (que.Count > 0)
{
ZBinaryTreeNode <T> node = que.Dequeue();
items.Add(node.Value);
if (Root.LeftNode != null)
{
que.Enqueue(Root.LeftNode);
}
if (Root.RightNode != null)
{
que.Enqueue(Root.RightNode);
}
}
return(items);
}
public ZBinaryTreeNode <T> FindParent(T data)
{
ZBinaryTreeNode <T> current = Root;
ZBinaryTreeNode <T> parent = null;
if (Root.Value.Equals(data))
{
return(parent);
}
while (current != null)
{
int compareResult = current.Value.CompareTo(data);
if (compareResult == 0)
{
return(parent);
}
else if (compareResult < 0)
{
parent = current;
current = current.LeftNode;
}
else
{
parent = current;
current = current.RightNode;
}
}
return(parent);
}
public void Delete(T data)
{
ZBinaryTreeNode <T> node = null;
ZBinaryTreeNode <T> parent = FindParent(data);
if (parent != null)
{
if (parent.LeftNode != null && parent.LeftNode.Value.Equals(data))
{
node = parent.LeftNode;
//case1: has no children.
if (node.LeftNode == null && node.RightNode == null)
{
parent.LeftNode = null;
}
//case2: has left child but no right child.
else if (node.RightNode == null)
{
parent.LeftNode = node.LeftNode;
}
//case3: has right child and right child has no left child of it's own.
else if (node.RightNode.LeftNode == null)
{
parent.LeftNode = node.RightNode;
}
//case4: Finally, if the deleted node's right child does have a left child, then the deleted node needs to be replaced by the deleted node's right child's left-most descendant. That is, we replace the deleted node with the deleted node's right subtree's smallest value.
else
{
ZBinaryTreeNode <T> minNode = FindMin(node.RightNode);
parent.LeftNode = minNode;
}
}
else if (parent.RightNode != null && parent.RightNode.Value.Equals(data))
{
node = parent.RightNode;
//case1: has no children.
if (node.LeftNode == null && node.RightNode == null)
{
parent.RightNode = null;
}
//case2: has left child but no right child.
else if (node.RightNode == null)
{
parent.RightNode = node.LeftNode;
}
//case3: has right child and right child has no left child of it's own.
else if (node.RightNode.LeftNode == null)
{
parent.RightNode = node.RightNode;
}
//case4: Finally, if the deleted node's right child does have a left child, then the deleted node needs to be replaced by the deleted node's right child's left-most descendant. That is, we replace the deleted node with the deleted node's right subtree's smallest value.
else
{
ZBinaryTreeNode <T> minNode = FindMin(node.RightNode);
parent.RightNode = minNode;
}
}
}
}
private void PostOrder(ZBinaryTreeNode <T> node, List <T> items)
{
if (node != null)
{
PostOrder(node.LeftNode, items);
PostOrder(node.RightNode, items);
items.Add(node.Value);
}
}
public ZBinaryTreeNode <T> FindMin(ZBinaryTreeNode <T> node)
{
if (node.LeftNode == null)
{
return(node);
}
else
{
return(FindMax(node.LeftNode));
}
}
public void Add(T data)
{
ZBinaryTreeNode <T> current = Root;
if (current == null)
{
Root = new ZBinaryTreeNode <T>(data);
}
else
{
while (true)
{
int compareResult = current.Value.CompareTo(data);
if (compareResult < 0)
{
if (current.RightNode == null)
{
current.RightNode = new ZBinaryTreeNode <T>(data);
return;
}
else
{
current = current.RightNode;
}
}
if (compareResult > 0)
{
if (current.LeftNode == null)
{
current.LeftNode = new ZBinaryTreeNode <T>(data);
return;
}
else
{
current = current.LeftNode;
}
}
else
{
return;
}
}
}
}
private int CountChildren(ZBinaryTreeNode <T> node)
{
if (node == null)
{
return(0);
}
int left = CountChildren(node.LeftNode);
int right = CountChildren(node.RightNode);
if (left >= right)
{
return(left + 1);
}
else
{
return(right + 1);
}
}
private bool GetAncesters(ZBinaryTreeNode <T> node, T data, List <ZBinaryTreeNode <T> > items)
{
if (node != null)
{
if (!node.Value.Equals(data))
{
if (GetAncesters(node.LeftNode, data, items) || GetAncesters(node.RightNode, data, items))
{
items.Add(node);
return(true);
}
}
else
{
return(true);
}
}
return(false);
}
public ZBinaryTreeNode <T> Search(T data)
{
ZBinaryTreeNode <T> match = null;
ZQueue <ZBinaryTreeNode <T> > que = new ZQueue <ZBinaryTreeNode <T> >();
if (Root != null)
{
if (data.Equals(Root.Value))
{
return(Root);
}
if (Root.LeftNode != null)
{
que.Enqueue(Root.LeftNode);
}
if (Root.RightNode != null)
{
que.Enqueue(Root.RightNode);
}
}
while (que.Count > 0)
{
ZBinaryTreeNode <T> node = que.Dequeue();
if (data.Equals(node.Value))
{
return(node);
}
if (Root.LeftNode != null)
{
que.Enqueue(Root.LeftNode);
}
if (Root.RightNode != null)
{
que.Enqueue(Root.RightNode);
}
}
return(match);
}
public int CountFullNodes()
{
int total = 0;
ZQueue <ZBinaryTreeNode <T> > que = new ZQueue <ZBinaryTreeNode <T> >();
if (Root != null)
{
if (Root.LeftNode != null && Root.RightNode != null)
{
total++;
}
if (Root.LeftNode != null)
{
que.Enqueue(Root.LeftNode);
}
if (Root.RightNode != null)
{
que.Enqueue(Root.RightNode);
}
}
while (que.Count > 0)
{
ZBinaryTreeNode <T> node = que.Dequeue();
if (Root.LeftNode != null && Root.RightNode != null)
{
total++;
}
if (Root.LeftNode != null)
{
que.Enqueue(Root.LeftNode);
}
if (Root.RightNode != null)
{
que.Enqueue(Root.RightNode);
}
}
return(total);
}
public ZBinaryTreeNode(T data, ZBinaryTreeNode <T> left, ZBinaryTreeNode <T> right)
{
this.Value = data;
this.LeftNode = left;
this.RightNode = right;
}
