public void InorderTraversal(BinaryTreeNode root)
{
if (root != null)
{
InorderTraversal(root.Left);
Console.WriteLine(root.Key);
InorderTraversal(root.Right);
}
}
internal bool Search(BinaryTreeNode root,int data)
{
if (root == null)
return false;
if (root.data == data)
return true;
else if (root.data < data)
return Search(root.right, data);
else
return Search(root.left, data);
}
internal BinaryTreeNode Insert(ref BinaryTreeNode root,BinaryTreeNode newNode)
{
if (root == null)
{
root = newNode;
}
else {
if (root.data > newNode.data)
Insert(ref root.left, newNode);
else
Insert(ref root.right, newNode);
}
return root;
}
public void BinaryTreeInsert(int k)
{
BinaryTreeNode node = new BinaryTreeNode(k);
if (Root == null)
{
Root = node;
}
else if (Root.Left == null) Root.Left = node;
else if (Root.Right == null) Root.Right = node;
else
{
Queue<BinaryTreeNode> q = new Queue<BinaryTreeNode>();
q.Enqueue(Root);
while (q.Any())
{
BinaryTreeNode temp = q.Dequeue();
if (temp.Left == null)
{
temp.Left = node;
break;
}
else if (temp.Right == null)
{
temp.Right = node;
break;
}
else
{
q.Enqueue(temp.Left);
q.Enqueue(temp.Right);
}
}
//Free Queue and delete
}
}
void preOrderValues(BinaryTreeNode current)
{
if (current != null) {
preOrder.Add(current.data);
preOrderValues(current.left);
preOrderValues(current.right);
}
}
private BinaryTreeNode SearchIterative(BinaryTreeNode root, int key)
{
if (root == null)
{
return null;
}
else
{
BinaryTreeNode p = root;
while (p != null)
{
if (p.Key == key)
{
return p;
}
else if (key < p.Key)
{
p = p.Left;
}
else
{
p = p.Right;
}
}
return null;
}
}
private BinaryTreeNode SearchRecursiveBinaryTree(BinaryTreeNode root, int k)
{
if (root == null) return null;
if(root.Key ==k)
{
return root;
}
BinaryTreeNode leftSearch = SearchRecursiveBinaryTree(root.Left, k);
if(leftSearch!=null)
{
return leftSearch;
}
else
{
return SearchRecursiveBinaryTree(root.Right, k);
}
}
private bool isSymmetric(BinaryTreeNode leftRoot, BinaryTreeNode rightRoot)
{
if (leftRoot == null && rightRoot == null)
{
return true;
}
else if (leftRoot != null && rightRoot != null)
{
return (leftRoot.Key == rightRoot.Key && isSymmetric(leftRoot.Left, rightRoot.Right) && isSymmetric(leftRoot.Right, rightRoot.Left));
}
else
{
return false;
}
}
/// <summary>
/// Here it is assumed that nodes are present in the binary tree
/// </summary>
/// <param name="root"></param>
/// <param name="p"></param>
/// <param name="q"></param>
/// <returns></returns>
private BinaryTreeNode LCA_BinaryTree(BinaryTreeNode root, BinaryTreeNode p, BinaryTreeNode q)
{
if(root == null)
{
return null;
}
if(root==p|| root== q)
{
return root;
}
BinaryTreeNode leftLca = LCA_BinaryTree(root.Left, p, q);
BinaryTreeNode rightLca = LCA_BinaryTree(root.Right, p, q);
if(leftLca != null && rightLca != null)
{
//one on left and one on right scenario
return root;
}
else
{
//Both left or both right scenario
return leftLca != null ? leftLca : rightLca;
}
}
private void InsertIterative(int key)
{
BinaryTreeNode node = new BinaryTreeNode(key);
if (Root == null)
{
Root = new BinaryTreeNode(key);
}
else
{
BinaryTreeNode p = Root;
BinaryTreeNode prev = null;
while (p != null)
{
prev = p;
if (key <= p.Key)
{
p = p.Left;
}
else
{
p = p.Right;
}
}
if (key <= prev.Key)
{
prev.Left = node;
}
else
{
prev.Right = node;
}
}
}
private BinaryTreeNode InsertRecursive(BinaryTreeNode root, int key)
{
if (root == null)
{
root = new BinaryTreeNode(key);
}
else
{
if (key <= root.Key)
{
root.Left = InsertRecursive(root.Left, key);
}
else
{
root.Right = InsertRecursive(root.Right, key);
}
}
return root;
}
public BinaryTreeNode(int data, BinaryTreeNode left, BinaryTreeNode right)
{
this.data = data;
this.left = left;
this.right = right;
}
private int HeightIterative(BinaryTreeNode root)
{
// Time Complexity : O(n) - have to visit all nodes
// Space complexity : O(width of tree)
if (root == null) return 0;
int level = 0;
Queue<BinaryTreeNode> q = new Queue<BinaryTreeNode>();
BinaryTreeNode marker = null;
q.Enqueue(root);
q.Enqueue(marker);
while (q.Any())
{
BinaryTreeNode temp = q.Dequeue();
if (temp == marker)
{
//End of level. Increment
level++;
if (q.Any())
{
q.Enqueue(marker);
}
else
{ //Reached the end.
break;
}
}
else
{
if (temp.Left != null)
{
q.Enqueue(temp.Left);
}
if (temp.Right != null)
{
q.Enqueue(temp.Right);
}
}
}
return level;
}
void PreOrderIterative(BinaryTreeNode current)
{
Stack<BinaryTreeNode> s = new Stack<BinaryTreeNode>();
s.Push(current);
while(s.Count!=0)
{
BinaryTreeNode temp= s.Pop();
Console.WriteLine(temp);
s.Push(temp.right);
s.Push(temp.left);
}
}
void PreOrder(BinaryTreeNode current)
{
if (current == null) return;
Console.WriteLine(current);
PreOrder(current.left);
PreOrder(current.right);
}
public BinarySearchTree()
{
root = null;
}
bool MatchTree(BinaryTreeNode n1, BinaryTreeNode n2)
{
if (n2 == null)
return true;
if (n1 == null)
return false;
if (n1.data == n2.data)
return MatchTree(n1.left, n2.left)
&& MatchTree(n1.right, n2.right);
else
return false;
}
void LeveLOrder(BinaryTreeNode current)
{
Queue<BinaryTreeNode> q = new Queue<BinaryTreeNode>();
q.Enqueue(current);
while (q.Count != 0)
{
BinaryTreeNode temp = q.Dequeue();
Console.WriteLine(temp);
if (temp.left != null)
q.Enqueue(temp.left);
if (temp.right != null)
q.Enqueue(temp.right);
}
}
private BinaryTreeNode FindMinInBST(BinaryTreeNode root)
{
if (root == null) return null;
BinaryTreeNode p = root;
while(p.Left!=null)
{
p = p.Left;
}
return p;
}
int TreeHeight(BinaryTreeNode root)
{
if (root == null)
return 0;
return 1 + Math.Max(TreeHeight(root.right), TreeHeight(root.left));
}
private int HeightRecursive(BinaryTreeNode root)
{
// Time Complexity : O(n) - have to visit all nodes
// Space complexity : O(n)
if (root == null)
{
return 0;
}
else
{
int lheight = HeightRecursive(root.Left);
int rheight = HeightRecursive(root.Right);
return 1 + Math.Max(lheight, rheight);
}
}
public BinaryTreeNode(int data)
{
this.data = data;
this.left = null;
this.right = null;
}
public BinaryTreeNode(int data, BinaryTreeNode left, BinaryTreeNode right)
{
this.data = data;
this.left = left;
this.right = right;
}
public clsBinarySearchTree()
{
_root = null;
}
private int IsHeightBalanced(BinaryTreeNode root)
{
if (root == null)
{
return 0;
}
int lh = IsHeightBalanced(root.Left);
if (lh == -2) return -2;
int rh = IsHeightBalanced(root.Right);
if (rh == -2) return -2;
if (Math.Abs(lh - rh) > 1) return -2;
return (1 + Math.Max(lh, rh));
}
public void Clear()
{
_root = null;
}
private void KthNodeInorder(BinaryTreeNode root, ref BinaryTreeNode KthNode, ref int count, int k)
{
if (root == null)
{
return;
}
KthNodeInorder(root.Left, ref KthNode, ref count, k);
count++;
if (count == k)
{
KthNode = root;
return;
}
KthNodeInorder(root.Right,ref KthNode ,ref count, k);
}
public BinaryTreeNode NextRight; //Used in some of the problems
public BinaryTreeNode(int val, BinaryTreeNode left = null, BinaryTreeNode right = null)
{
Value = val;
Left = left;
Right = right;
}
private BinaryTreeNode LCA_BST(BinaryTreeNode root, int p , int q)
{
if (root == null) return null;
BinaryTreeNode temp = root;
while(temp!=null)
{
if(p< temp.Key && q < temp.Key)
{
//Go left
temp = temp.Left;
}
else if(p> temp.Key && q> temp.Key)
{
//Go right
temp = temp.Right;
}
else
{
//found lca
return temp;
}
}
return null;
}
public void KthNodeInorder(ref BinaryTreeNode KthNode, int k)
{
int count = 0;
KthNodeInorder(Root, ref KthNode, ref count, k);
}
private BinaryTreeNode SearchRecursive(BinaryTreeNode root, int key)
{
if (root == null) return null;
if (root.Key == key) return root;
if (key < root.Key)
{
return SearchRecursive(root.Left, key);
}
else
{
return SearchRecursive(root.Right, key);
}
}
public void PrintDoublyLinkedList(BinaryTreeNode root)
{
//Print the doubly linked list
if (Root == null) return;
if(Root.Left==null && Root.Right == null)
{
Console.WriteLine(Root.Key);
return;
}
BinaryTreeNode p = Root;
while (p.Left != null) p = p.Left;
while(p!=null)
{
Console.WriteLine(p.Key);
p = p.Right;
}
}
public void BinaryTreeToDoublyLinkedList(ref BinaryTreeNode visited)
{
BinaryTreeToDoublyLinkedList(Root, ref visited);
}
private void BinaryTreeToDoublyLinkedList(BinaryTreeNode root, ref BinaryTreeNode visited)
{
if (root == null) return;
BinaryTreeToDoublyLinkedList(root.Left, ref visited);
if(visited!=null)
{
visited.Right = root;
root.Left = visited;
}
visited = root;
//traverse right
BinaryTreeToDoublyLinkedList(root.Right, ref visited);
}
public void Insert(int key, bool isIterative = false)
{
if (isIterative)
{
InsertIterative(key);
}
else
{
BinaryTreeNode temp = InsertRecursive(Root, key);
if (Root == null)
{
Root = temp;
}
}
}
public BinaryTreeNode(int data)
{
this.data = data;
this.left = null;
this.right = null;
}