Inorder traversal of binary tree using stack in c#

Csharp program for Inorder traversal of binary tree using stack. Here problem description and explanation.

// Include namespace system
using System;
// Csharp program for
// Inorder traversal without recursion
// Using stack

// Binary Tree node
public class TreeNode
{
	public int data;
	public TreeNode left;
	public TreeNode right;
	// Make a tree node
	public TreeNode(int data)
	{
		// Set node data
		this.data = data;
		this.left = null;
		this.right = null;
	}
}
public class StackNode
{
	public TreeNode element;
	public StackNode next;
	public StackNode(TreeNode element)
	{
		this.element = element;
		this.next = null;
	}
}
// Stack Class
public class MyStack
{
	public StackNode top;
	public int size;
	public MyStack()
	{
		this.top = null;
		this.size = 0;
	}
	// Add new element into stack
	public void push(TreeNode element)
	{
		// Create new node
		var node = new StackNode(element);
		node.next = this.top;
		// new node is new top
		this.top = node;
		// Increase the size
		this.size += 1;
	}
	// Remove top element of the stack
	public void pop()
	{
		if (this.top != null)
		{
			// next node is new top
			this.top = this.top.next;
			// Reduce size
			this.size -= 1;
		}
	}
	// Returns the status of empty or non empty stacks
	public bool isEmpty()
	{
		if (this.size > 0 && this.top != null)
		{
			return false;
		}
		else
		{
			return true;
		}
	}
	// Return top element of stack
	public TreeNode peek()
	{
		if (this.isEmpty())
		{
			return null;
		}
		return this.top.element;
	}
}
public class BinaryTree
{
	public TreeNode root;
	public BinaryTree()
	{
		// Set initial tree root to null
		this.root = null;
	}
	// Display Inorder view of binary tree
	public void inorder()
	{
		if (this.root != null)
		{
			// Make new stack
			var s = new MyStack();
			var node = this.root;
			// Display tree element
			while (!s.isEmpty() || node != null)
			{
				if (node != null)
				{
					// Add current node
					s.push(node);
					// Visit to left subtree
					node = node.left;
				}
				else
				{
					// When node is null
					// Get stack top element
					node = s.peek();
					// Display node value
					Console.Write(" " + node.data);
					// Remove top element of the stack
					s.pop();
					// Visit to left subtree of current node
					node = node.right;
				}
			}
		}
		else
		{
			Console.Write("Empty Linked List\n");
		}
	}
	public static void Main(String[] args)
	{
		// Create new tree
		var tree = new BinaryTree();
		/*
		    Construct Binary Tree
		    -----------------------
		        15
		       /  \
		      24   54
		     /    /  \
		    35   62   13
		*/
		// Add tree nodes
		tree.root = new TreeNode(15);
		tree.root.left = new TreeNode(24);
		tree.root.right = new TreeNode(54);
		tree.root.right.right = new TreeNode(13);
		tree.root.right.left = new TreeNode(62);
		tree.root.left.left = new TreeNode(35);
		// Display result
		tree.inorder();
	}
}

Output

 35 24 15 62 54 13


Please share your knowledge to improve code and content standard. Also submit your doubts, and test case. We improve by your feedback. We will try to resolve your query as soon as possible.

New Comment







© 2021, kalkicode.com, All rights reserved