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Print binary search tree in top down level in spiral manner

Here given code implementation process.

import java.util.Vector;
import java.util.HashMap;
// Java program for
// Print binary search tree in top down level in spiral manner
class TreeNode
{
	// Data value 
	public int data;
	// Indicates left and right subtree
	public TreeNode left;
	public TreeNode right;
	public TreeNode(int data)
	{
		this.data = data;
		this.left = null;
		this.right = null;
	}
}
public class BinarySearchTree
{
	public TreeNode root;
	public BinarySearchTree()
	{
		this.root = null;
	}
	public void addNode(int data)
	{
		TreeNode node = new TreeNode(data);
		if (this.root == null)
		{
			this.root = node;
		}
		else
		{
			TreeNode find = this.root;
			// Add new node to proper position
			while (find != null)
			{
				if (find.data >= data)
				{
					if (find.left == null)
					{
						find.left = node;
						return;
					}
					else
					{
						// Visit left sub-tree
						find = find.left;
					}
				}
				else
				{
					if (find.right == null)
					{
						find.right = node;
						return;
					}
					else
					{
						// Visit right sub-tree
						find = find.right;
					}
				}
			}
		}
	}
	public void findLevelNode(TreeNode node, 
                               HashMap < Integer, Vector < Integer >> record,
                               int level)
	{
		if (node != null)
		{
			if (!record.containsKey(level))
			{
				record.put(level, new Vector < Integer > ());
			}
			// Get level node
			record.get(level).add(node.data);
			findLevelNode(node.left, record, level + 1);
			findLevelNode(node.right, record, level + 1);
		}
	}
	public void printLevelLR(HashMap < Integer, 
                              Vector < Integer >> record, int level)
	{
		for (int i = 0; i < record.get(level).size(); ++i)
		{
			System.out.print("  " + record.get(level).get(i));
		}
		System.out.print("\n");
	}
	public void printLevelRL(HashMap < Integer, 
                              Vector < Integer >> record, int level)
	{
		for (int i = record.get(level).size() - 1; i >= 0; --i)
		{
			System.out.print("  " + record.get(level).get(i));
		}
		System.out.print("\n");
	}
	public void alternateLevel()
	{
		if (this.root != null)
		{
			HashMap < Integer, Vector < Integer >> record =
              new HashMap < Integer, Vector < Integer >> ();
			findLevelNode(this.root, record, 1);
			int i = 1;
			int j = record.size();
			while (i <= j)
			{
				if (i != j)
				{
					// Top level
					printLevelLR(record, i);
					// Bottom level
					printLevelRL(record, j);
					i++;
					j--;
				}
				else
				{
					// Middle level
					printLevelLR(record, i);
					i++;
				}
			}
		}
	}
	public static void main(String[] args)
	{
		BinarySearchTree tree = new BinarySearchTree();
		/*
		        
		           70
		          /  \
		         /    \
		        60     80
		       / \    /  \
		      30  65 75   90
		     / \     / \   \
		    10  40  73  77  95

		*/
		tree.addNode(70);
		tree.addNode(60);
		tree.addNode(30);
		tree.addNode(65);
		tree.addNode(10);
		tree.addNode(40);
		tree.addNode(80);
		tree.addNode(75);
		tree.addNode(73);
		tree.addNode(77);
		tree.addNode(90);
		tree.addNode(95);
		tree.alternateLevel();
	}
}

Output

  70
  95  77  73  40  10
  60  80
  90  75  65  30
// Include header file
#include <iostream>
#include <unordered_map>
#include <vector>

using namespace std;
// C++ program for
// Print binary search tree in top down level in spiral manner
class TreeNode
{
	public:
	// Data value
	int data;
	// Indicates left and right subtree
	TreeNode *left;
	TreeNode *right;
	TreeNode(int data)
	{
		this->data = data;
		this->left = NULL;
		this->right = NULL;
	}
};
class BinarySearchTree
{
	public: TreeNode *root;
	BinarySearchTree()
	{
		this->root = NULL;
	}
	void addNode(int data)
	{
		TreeNode *node = new TreeNode(data);
		if (this->root == NULL)
		{
			this->root = node;
		}
		else
		{
			TreeNode *find = this->root;
			// Add new node to proper position
			while (find != NULL)
			{
				if (find->data >= data)
				{
					if (find->left == NULL)
					{
						find->left = node;
						return;
					}
					else
					{
						// Visit left sub-tree
						find = find->left;
					}
				}
				else
				{
					if (find->right == NULL)
					{
						find->right = node;
						return;
					}
					else
					{
						// Visit right sub-tree
						find = find->right;
					}
				}
			}
		}
	}
	void findLevelNode(TreeNode *node, 
                       unordered_map < int, vector < int > > &record, int level)
	{
		if (node != NULL)
		{
			
			// Get level node
			record[level].push_back(node->data);
			this->findLevelNode(node->left, record, level + 1);
			this->findLevelNode(node->right, record, level + 1);
		}
	}
	void printLevelLR(unordered_map < int, vector < int > > record, 
                      int level)
	{
		for (int i = 0; i < record[level].size(); ++i)
		{
			cout << "  " << record[level].at(i);
		}
		cout << "\n";
	}
	void printLevelRL(unordered_map < int, vector < int > > record, 
                      int level)
	{
		for (int i = record[level].size() - 1; i >= 0; --i)
		{
			cout << "  " << record[level].at(i);
		}
		cout << "\n";
	}
	void alternateLevel()
	{
		if (this->root != NULL)
		{
			unordered_map < int, vector < int > > record;
			this->findLevelNode(this->root, record, 1);
			int i = 1;
			int j = record.size();
			while (i <= j)
			{
				if (i != j)
				{
					// Top level
					this->printLevelLR(record, i);
					// Bottom level
					this->printLevelRL(record, j);
					i++;
					j--;
				}
				else
				{
					// Middle level
					this->printLevelLR(record, i);
					i++;
				}
			}
		}
	}
};
int main()
{
	BinarySearchTree *tree = new BinarySearchTree();
	/*
	           70
	          /  \
	         /    \
	        60     80
	       / \    /  \
	      30  65 75   90
	     / \     / \   \
	    10  40  73  77  95
	*/
	tree->addNode(70);
	tree->addNode(60);
	tree->addNode(30);
	tree->addNode(65);
	tree->addNode(10);
	tree->addNode(40);
	tree->addNode(80);
	tree->addNode(75);
	tree->addNode(73);
	tree->addNode(77);
	tree->addNode(90);
	tree->addNode(95);
	tree->alternateLevel();
	return 0;
}

Output

  70
  95  77  73  40  10
  60  80
  90  75  65  30
package main
import "fmt"
// Go program for
// Print binary search tree in top down level in spiral manner
type TreeNode struct {
	// Data value
	data int
	// Indicates left and right subtree
	left * TreeNode
	right * TreeNode
}
func getTreeNode(data int) * TreeNode {
	var me *TreeNode = &TreeNode {}
	me.data = data
	me.left = nil
	me.right = nil
	return me
}
type BinarySearchTree struct {
	root * TreeNode
}
func getBinarySearchTree() * BinarySearchTree {
	var me *BinarySearchTree = &BinarySearchTree {}
	me.root = nil
	return me
}
func(this *BinarySearchTree) addNode(data int) {
	var node * TreeNode = getTreeNode(data)
	if this.root == nil {
		this.root = node
	} else {
		var find * TreeNode = this.root
		// Add new node to proper position
		for (find != nil) {
			if find.data >= data {
				if find.left == nil {
					find.left = node
					return
				} else {
					// Visit left sub-tree
					find = find.left
				}
			} else {
				if find.right == nil {
					find.right = node
					return
				} else {
					// Visit right sub-tree
					find = find.right
				}
			}
		}
	}
}
func(this BinarySearchTree) findLevelNode(node * TreeNode, 
	record map[int][]int, level int) {
	if node != nil {
	
		// Get level node
		record[level] = append(record[level], node.data)
		this.findLevelNode(node.left, record, level + 1)
		this.findLevelNode(node.right, record, level + 1)
	}
}
func(this BinarySearchTree) printLevelLR(record map[int][]int, level int) {
	for i := 0 ; i < len(record[level]) ; i++ {
		fmt.Print("  ", record[level][i])
	}
	fmt.Print("\n")
}
func(this BinarySearchTree) printLevelRL(record map[int][]int, level int) {
	for i := len(record[level]) - 1 ; i >= 0 ; i-- {
		fmt.Print("  ", record[level][i])
	}
	fmt.Print("\n")
}
func(this BinarySearchTree) alternateLevel() {
	if this.root != nil {
		var record = make(map[int][]int)
		this.findLevelNode(this.root, record, 1)
		var i int = 1
		var j int = len(record)
		for (i <= j) {
			if i != j {
				// Top level
				this.printLevelLR(record, i)
				// Bottom level
				this.printLevelRL(record, j)
				i++
				j--
			} else {
				// Middle level
				this.printLevelLR(record, i)
				i++
			}
		}
	}
}
func main() {
	var tree * BinarySearchTree = getBinarySearchTree()
	/*
	           70
	          /  \
	         /    \
	        60     80
	       / \    /  \
	      30  65 75   90
	     / \     / \   \
	    10  40  73  77  95
	*/
	tree.addNode(70)
	tree.addNode(60)
	tree.addNode(30)
	tree.addNode(65)
	tree.addNode(10)
	tree.addNode(40)
	tree.addNode(80)
	tree.addNode(75)
	tree.addNode(73)
	tree.addNode(77)
	tree.addNode(90)
	tree.addNode(95)
	tree.alternateLevel()
}

Output

  70
  95  77  73  40  10
  60  80
  90  75  65  30
// Include namespace system
using System;
using System.Collections.Generic;
// Csharp program for
// Print binary search tree in top down level in spiral manner
public class TreeNode
{
	// Data value
	public int data;
	// Indicates left and right subtree
	public TreeNode left;
	public TreeNode right;
	public TreeNode(int data)
	{
		this.data = data;
		this.left = null;
		this.right = null;
	}
}
public class BinarySearchTree
{
	public TreeNode root;
	public BinarySearchTree()
	{
		this.root = null;
	}
	public void addNode(int data)
	{
		TreeNode node = new TreeNode(data);
		if (this.root == null)
		{
			this.root = node;
		}
		else
		{
			TreeNode find = this.root;
			// Add new node to proper position
			while (find != null)
			{
				if (find.data >= data)
				{
					if (find.left == null)
					{
						find.left = node;
						return;
					}
					else
					{
						// Visit left sub-tree
						find = find.left;
					}
				}
				else
				{
					if (find.right == null)
					{
						find.right = node;
						return;
					}
					else
					{
						// Visit right sub-tree
						find = find.right;
					}
				}
			}
		}
	}
	public void findLevelNode(TreeNode node, 
                               Dictionary < int, List < int >> record, 
                               int level)
	{
		if (node != null)
		{
			if (!record.ContainsKey(level))
			{
				record.Add(level, new List < int > ());
			}
			// Get level node
			record[level].Add(node.data);
			this.findLevelNode(node.left, record, level + 1);
			this.findLevelNode(node.right, record, level + 1);
		}
	}
	public void printLevelLR(Dictionary < int, List < int >> record, 
                              int level)
	{
		for (int i = 0; i < record[level].Count; ++i)
		{
			Console.Write("  " + record[level][i]);
		}
		Console.Write("\n");
	}
	public void printLevelRL(Dictionary < int, List < int >> record, 
                              int level)
	{
		for (int i = record[level].Count - 1; i >= 0; --i)
		{
			Console.Write("  " + record[level][i]);
		}
		Console.Write("\n");
	}
	public void alternateLevel()
	{
		if (this.root != null)
		{
			Dictionary < int, List < int >> record = 
              new Dictionary < int, List < int >> ();
			this.findLevelNode(this.root, record, 1);
			int i = 1;
			int j = record.Count;
			while (i <= j)
			{
				if (i != j)
				{
					// Top level
					this.printLevelLR(record, i);
					// Bottom level
					this.printLevelRL(record, j);
					i++;
					j--;
				}
				else
				{
					// Middle level
					this.printLevelLR(record, i);
					i++;
				}
			}
		}
	}
	public static void Main(String[] args)
	{
		BinarySearchTree tree = new BinarySearchTree();
		/*
		           70
		          /  \
		         /    \
		        60     80
		       / \    /  \
		      30  65 75   90
		     / \     / \   \
		    10  40  73  77  95
		*/
		tree.addNode(70);
		tree.addNode(60);
		tree.addNode(30);
		tree.addNode(65);
		tree.addNode(10);
		tree.addNode(40);
		tree.addNode(80);
		tree.addNode(75);
		tree.addNode(73);
		tree.addNode(77);
		tree.addNode(90);
		tree.addNode(95);
		tree.alternateLevel();
	}
}

Output

  70
  95  77  73  40  10
  60  80
  90  75  65  30
<?php
// Php program for
// Print binary search tree in top down level in spiral manner
class TreeNode
{
    // Data value
    public $data;
    // Indicates left and right subtree
    public $left;
    public $right;
    public  function __construct($data)
    {
        $this->data = $data;
        $this->left = NULL;
        $this->right = NULL;
    }
}
class BinarySearchTree
{
    public $root;
    public  function __construct()
    {
        $this->root = NULL;
    }
    public  function addNode($data)
    {
        $node = new TreeNode($data);
        if ($this->root == NULL)
        {
            $this->root = $node;
        }
        else
        {
            $find = $this->root;
            // Add new node to proper position
            while ($find != NULL)
            {
                if ($find->data >= $data)
                {
                    if ($find->left == NULL)
                    {
                        $find->left = $node;
                        return;
                    }
                    else
                    {
                        // Visit left sub-tree
                        $find = $find->left;
                    }
                }
                else
                {
                    if ($find->right == NULL)
                    {
                        $find->right = $node;
                        return;
                    }
                    else
                    {
                        // Visit right sub-tree
                        $find = $find->right;
                    }
                }
            }
        }
    }
    public  function findLevelNode($node, &$record, $level)
    {
        if ($node != NULL)
        {
            if (!array_key_exists($level, $record))
            {
                $record[$level] = array();
            }
            // Get level node
            $record[$level][] = $node->data;
            $this->findLevelNode($node->left, $record, $level + 1);
            $this->findLevelNode($node->right, $record, $level + 1);
        }
    }
    public  function printLevelLR($record, $level)
    {
        for ($i = 0; $i < count($record[$level]); ++$i)
        {
            echo("  ".$record[$level][$i]);
        }
        echo("\n");
    }
    public  function printLevelRL($record, $level)
    {
        for ($i = count($record[$level]) - 1; $i >= 0; --$i)
        {
            echo("  ".$record[$level][$i]);
        }
        echo("\n");
    }
    public  function alternateLevel()
    {
        if ($this->root != NULL)
        {
            $record = array();
            $this->findLevelNode($this->root, $record, 1);
            $i = 1;
            $j = count($record);
            while ($i <= $j)
            {
                if ($i != $j)
                {
                    // Top level
                    $this->printLevelLR($record, $i);
                    // Bottom level
                    $this->printLevelRL($record, $j);
                    $i++;
                    $j--;
                }
                else
                {
                    // Middle level
                    $this->printLevelLR($record, $i);
                    $i++;
                }
            }
        }
    }
}

function main()
{
    $tree = new BinarySearchTree();
    /*
               70
              /  \
             /    \
            60     80
           / \    /  \
          30  65 75   90
         / \     / \   \
        10  40  73  77  95
    */
    $tree->addNode(70);
    $tree->addNode(60);
    $tree->addNode(30);
    $tree->addNode(65);
    $tree->addNode(10);
    $tree->addNode(40);
    $tree->addNode(80);
    $tree->addNode(75);
    $tree->addNode(73);
    $tree->addNode(77);
    $tree->addNode(90);
    $tree->addNode(95);
    $tree->alternateLevel();
}
main();

Output

  70
  95  77  73  40  10
  60  80
  90  75  65  30
// Node JS program for
// Print binary search tree in top down level in spiral manner
class TreeNode
{
	constructor(data)
	{
		this.data = data;
		this.left = null;
		this.right = null;
	}
}
class BinarySearchTree
{
	constructor()
	{
		this.root = null;
	}
	addNode(data)
	{
		var node = new TreeNode(data);
		if (this.root == null)
		{
			this.root = node;
		}
		else
		{
			var find = this.root;
			// Add new node to proper position
			while (find != null)
			{
				if (find.data >= data)
				{
					if (find.left == null)
					{
						find.left = node;
						return;
					}
					else
					{
						// Visit left sub-tree
						find = find.left;
					}
				}
				else
				{
					if (find.right == null)
					{
						find.right = node;
						return;
					}
					else
					{
						// Visit right sub-tree
						find = find.right;
					}
				}
			}
		}
	}
	findLevelNode(node, record, level)
	{
		if (node != null)
		{
			if (!record.has(level))
			{
				record.set(level, []);
			}
			// Get level node
			record.get(level).push(node.data);
			this.findLevelNode(node.left, record, level + 1);
			this.findLevelNode(node.right, record, level + 1);
		}
	}
	printLevelLR(record, level)
	{
		for (var i = 0; i < record.get(level).length; ++i)
		{
			process.stdout.write("  " + record.get(level)[i]);
		}
		process.stdout.write("\n");
	}
	printLevelRL(record, level)
	{
		for (var i = record.get(level).length - 1; i >= 0; --i)
		{
			process.stdout.write("  " + record.get(level)[i]);
		}
		process.stdout.write("\n");
	}
	alternateLevel()
	{
		if (this.root != null)
		{
			var record = new Map();
			this.findLevelNode(this.root, record, 1);
			var i = 1;
			var j = record.size;
			while (i <= j)
			{
				if (i != j)
				{
					// Top level
					this.printLevelLR(record, i);
					// Bottom level
					this.printLevelRL(record, j);
					i++;
					j--;
				}
				else
				{
					// Middle level
					this.printLevelLR(record, i);
					i++;
				}
			}
		}
	}
}

function main()
{
	var tree = new BinarySearchTree();
	/*
	           70
	          /  \
	         /    \
	        60     80
	       / \    /  \
	      30  65 75   90
	     / \     / \   \
	    10  40  73  77  95
	*/
	tree.addNode(70);
	tree.addNode(60);
	tree.addNode(30);
	tree.addNode(65);
	tree.addNode(10);
	tree.addNode(40);
	tree.addNode(80);
	tree.addNode(75);
	tree.addNode(73);
	tree.addNode(77);
	tree.addNode(90);
	tree.addNode(95);
	tree.alternateLevel();
}
main();

Output

  70
  95  77  73  40  10
  60  80
  90  75  65  30
#  Python 3 program for
#  Print binary search tree in top down level in spiral manner
class TreeNode :
	#  Data value
	#  Indicates left and right subtree
	def __init__(self, data) :
		self.data = data
		self.left = None
		self.right = None
	

class BinarySearchTree :
	def __init__(self) :
		self.root = None
	
	def addNode(self, data) :
		node = TreeNode(data)
		if (self.root == None) :
			self.root = node
		else :
			find = self.root
			#  Add new node to proper position
			while (find != None) :
				if (find.data >= data) :
					if (find.left == None) :
						find.left = node
						return
					else :
						#  Visit left sub-tree
						find = find.left
					
				else :
					if (find.right == None) :
						find.right = node
						return
					else :
						#  Visit right sub-tree
						find = find.right
					
				
			
		
	
	def findLevelNode(self, node, record, level) :
		if (node != None) :
			if (not(level in record.keys())) :
				record[level] = []
			
			#  Get level node
			record.get(level).append(node.data)
			self.findLevelNode(node.left, record, level + 1)
			self.findLevelNode(node.right, record, level + 1)
		
	
	def printLevelLR(self, record, level) :
		i = 0
		while (i < len(record.get(level))) :
			print("  ", record.get(level)[i], end = "")
			i += 1
		
		print(end = "\n")
	
	def printLevelRL(self, record, level) :
		i = len(record.get(level)) - 1
		while (i >= 0) :
			print("  ", record.get(level)[i], end = "")
			i -= 1
		
		print(end = "\n")
	
	def alternateLevel(self) :
		if (self.root != None) :
			record = dict()
			self.findLevelNode(self.root, record, 1)
			i = 1
			j = len(record)
			while (i <= j) :
				if (i != j) :
					#  Top level
					self.printLevelLR(record, i)
					#  Bottom level
					self.printLevelRL(record, j)
					i += 1
					j -= 1
				else :
					#  Middle level
					self.printLevelLR(record, i)
					i += 1
				
			
		
	

def main() :
	tree = BinarySearchTree()
	#           70
	#          /  \
	#         /    \
	#        60     80
	#       / \    /  \
	#      30  65 75   90
	#     / \     / \   \
	#    10  40  73  77  95
	tree.addNode(70)
	tree.addNode(60)
	tree.addNode(30)
	tree.addNode(65)
	tree.addNode(10)
	tree.addNode(40)
	tree.addNode(80)
	tree.addNode(75)
	tree.addNode(73)
	tree.addNode(77)
	tree.addNode(90)
	tree.addNode(95)
	tree.alternateLevel()

if __name__ == "__main__": main()

Output

   70
   95   77   73   40   10
   60   80
   90   75   65   30
#  Ruby program for
#  Print binary search tree in top down level in spiral manner
class TreeNode 
	# Define the accessor and reader of class TreeNode
	attr_reader :data, :left, :right
	attr_accessor :data, :left, :right
	#  Data value
	#  Indicates left and right subtree
	def initialize(data) 
		self.data = data
		self.left = nil
		self.right = nil
	end

end

class BinarySearchTree 
	# Define the accessor and reader of class BinarySearchTree
	attr_reader :root
	attr_accessor :root
	def initialize() 
		self.root = nil
	end

	def addNode(data) 
		node = TreeNode.new(data)
		if (self.root == nil) 
			self.root = node
		else
 
			find = self.root
			#  Add new node to proper position
			while (find != nil) 
				if (find.data >= data) 
					if (find.left == nil) 
						find.left = node
						return
					else
 
						#  Visit left sub-tree
						find = find.left
					end

				else
 
					if (find.right == nil) 
						find.right = node
						return
					else
 
						#  Visit right sub-tree
						find = find.right
					end

				end

			end

		end

	end

	def findLevelNode(node, record, level) 
		if (node != nil) 
			if (!record.key?(level)) 
				record[level] = []
			end

			#  Get level node
			record[level].push(node.data)
			self.findLevelNode(node.left, record, level + 1)
			self.findLevelNode(node.right, record, level + 1)
		end

	end

	def printLevelLR(record, level) 
		i = 0
		while (i < record[level].length) 
			print("  ", record[level][i])
			i += 1
		end

		print("\n")
	end

	def printLevelRL(record, level) 
		i = record[level].length - 1
		while (i >= 0) 
			print("  ", record[level][i])
			i -= 1
		end

		print("\n")
	end

	def alternateLevel() 
		if (self.root != nil) 
			record = Hash.new()
			self.findLevelNode(self.root, record, 1)
			i = 1
			j = record.size()
			while (i <= j) 
				if (i != j) 
					#  Top level
					self.printLevelLR(record, i)
					#  Bottom level
					self.printLevelRL(record, j)
					i += 1
					j -= 1
				else
 
					#  Middle level
					self.printLevelLR(record, i)
					i += 1
				end

			end

		end

	end

end

def main() 
	tree = BinarySearchTree.new()
	#           70
	#          /  \
	#         /    \
	#        60     80
	#       / \    /  \
	#      30  65 75   90
	#     / \     / \   \
	#    10  40  73  77  95
	tree.addNode(70)
	tree.addNode(60)
	tree.addNode(30)
	tree.addNode(65)
	tree.addNode(10)
	tree.addNode(40)
	tree.addNode(80)
	tree.addNode(75)
	tree.addNode(73)
	tree.addNode(77)
	tree.addNode(90)
	tree.addNode(95)
	tree.alternateLevel()
end

main()

Output

  70
  95  77  73  40  10
  60  80
  90  75  65  30

import scala.collection.mutable._;
// Scala program for
// Print binary search tree in top down level in spiral manner
class TreeNode(
	// Data value
	var data: Int,
		// Indicates left and right subtree
		var left: TreeNode,
			var right: TreeNode)
{
	def this(data: Int)
	{
		this(data, null, null);
	}
}
class BinarySearchTree(var root: TreeNode)
{
	def this()
	{
		this(null);
	}
	def addNode(data: Int): Unit = {
		var node: TreeNode = new TreeNode(data);
		if (this.root == null)
		{
			this.root = node;
		}
		else
		{
			var find: TreeNode = this.root;
			// Add new node to proper position
			while (find != null)
			{
				if (find.data >= data)
				{
					if (find.left == null)
					{
						find.left = node;
						return;
					}
					else
					{
						// Visit left sub-tree
						find = find.left;
					}
				}
				else
				{
					if (find.right == null)
					{
						find.right = node;
						return;
					}
					else
					{
						// Visit right sub-tree
						find = find.right;
					}
				}
			}
		}
	}
	def findLevelNode(node: TreeNode, 
                      record: HashMap[Int, ArrayBuffer[Int]], 
      					level: Int): Unit = {
		if (node != null)
		{
			if (!record.contains(level))
			{
				record.addOne(level, new ArrayBuffer[Int]());
			}
			// Get level node
			record.get(level).get += node.data;
			findLevelNode(node.left, record, level + 1);
			findLevelNode(node.right, record, level + 1);
		}
	}
	def printLevelLR(record: HashMap[Int, ArrayBuffer[Int]], 
      level: Int): Unit = {
		var i: Int = 0;
		while (i < record.get(level).get.size)
		{
			print("  " + record.get(level).get(i));
			i += 1;
		}
		print("\n");
	}
	def printLevelRL(record: HashMap[Int, ArrayBuffer[Int]], 
      level: Int): Unit = {
		var i: Int = record.get(level).get.size - 1;
		while (i >= 0)
		{
			print("  " + record.get(level).get(i));
			i -= 1;
		}
		print("\n");
	}
	def alternateLevel(): Unit = {
		if (this.root != null)
		{
			var record: HashMap[Int, ArrayBuffer[Int]] = new HashMap[Int, ArrayBuffer[Int]]();
			findLevelNode(this.root, record, 1);
			var i: Int = 1;
			var j: Int = record.size;
			while (i <= j)
			{
				if (i != j)
				{
					// Top level
					printLevelLR(record, i);
					// Bottom level
					printLevelRL(record, j);
					i += 1;
					j -= 1;
				}
				else
				{
					// Middle level
					printLevelLR(record, i);
					i += 1;
				}
			}
		}
	}
}
object Main
{
	def main(args: Array[String]): Unit = {
		var tree: BinarySearchTree = new BinarySearchTree();
		/*
		           70
		          /  \
		         /    \
		        60     80
		       / \    /  \
		      30  65 75   90
		     / \     / \   \
		    10  40  73  77  95
		*/
		tree.addNode(70);
		tree.addNode(60);
		tree.addNode(30);
		tree.addNode(65);
		tree.addNode(10);
		tree.addNode(40);
		tree.addNode(80);
		tree.addNode(75);
		tree.addNode(73);
		tree.addNode(77);
		tree.addNode(90);
		tree.addNode(95);
		tree.alternateLevel();
	}
}

Output

  70
  95  77  73  40  10
  60  80
  90  75  65  30
import Foundation;
// Swift 4 program for
// Print binary search tree in top down level in spiral manner
class TreeNode
{
	// Data value
	var data: Int;
	// Indicates left and right subtree
	var left: TreeNode? ;
	var right: TreeNode? ;
	init(_ data: Int)
	{
		self.data = data;
		self.left = nil;
		self.right = nil;
	}
}
class BinarySearchTree
{
	var root: TreeNode? ;
	init()
	{
		self.root = nil;
	}
	func addNode(_ data: Int)
	{
		let node: TreeNode = TreeNode(data);
		if (self.root == nil)
		{
			self.root = node;
		}
		else
		{
			var find: TreeNode? = self.root;
			// Add new node to proper position
			while (find  != nil)
			{
				if (find!.data >= data)
				{
					if (find!.left == nil)
					{
						find!.left = node;
						return;
					}
					else
					{
						// Visit left sub-tree
						find = find!.left;
					}
				}
				else
				{
					if (find!.right == nil)
					{
						find!.right = node;
						return;
					}
					else
					{
						// Visit right sub-tree
						find = find!.right;
					}
				}
			}
		}
	}
	func findLevelNode(_ node: TreeNode? , 
                       _ record : inout[Int : [Int] ], _ level: Int)
	{
		if (node  != nil)
		{
			if (!record.keys.contains(level))
			{
				record[level] = [Int]();
			}
			// Get level node
			record[level]!.append(node!.data);
			self.findLevelNode(node!.left, &record, level + 1);
			self.findLevelNode(node!.right, &record, level + 1);
		}
	}
	func printLevelLR(_ record: [Int : [Int] ], _ level: Int)
	{
		var i: Int = 0;
		while (i < record[level]!.count)
		{
			print("  ", record[level]![i], terminator: "");
			i += 1;
		}
		print(terminator: "\n");
	}
	func printLevelRL(_ record: [Int : [Int] ], _ level: Int)
	{
		var i: Int = record[level]!.count - 1;
		while (i >= 0)
		{
			print("  ", record[level]![i], terminator: "");
			i -= 1;
		}
		print(terminator: "\n");
	}
	func alternateLevel()
	{
		if (self.root  != nil)
		{
			var record: [Int : [Int]] = [Int : [Int] ]();
			self.findLevelNode(self.root, &record, 1);
			var i: Int = 1;
			var j: Int = record.count;
			while (i <= j)
			{
				if (i  != j)
				{
					// Top level
					self.printLevelLR(record, i);
					// Bottom level
					self.printLevelRL(record, j);
					i += 1;
					j -= 1;
				}
				else
				{
					// Middle level
					self.printLevelLR(record, i);
					i += 1;
				}
			}
		}
	}
}
func main()
{
	let tree: BinarySearchTree = BinarySearchTree();
	/*
	           70
	          /  \
	         /    \
	        60     80
	       / \    /  \
	      30  65 75   90
	     / \     / \   \
	    10  40  73  77  95
	*/
	tree.addNode(70);
	tree.addNode(60);
	tree.addNode(30);
	tree.addNode(65);
	tree.addNode(10);
	tree.addNode(40);
	tree.addNode(80);
	tree.addNode(75);
	tree.addNode(73);
	tree.addNode(77);
	tree.addNode(90);
	tree.addNode(95);
	tree.alternateLevel();
}
main();

Output

   70
   95   77   73   40   10
   60   80
   90   75   65   30
// Kotlin program for
// Print binary search tree in top down level in spiral manner
class TreeNode
{
	// Data value
	var data: Int;
	// Indicates left and right subtree
	var left: TreeNode ? ;
	var right: TreeNode ? ;
	constructor(data: Int)
	{
		this.data = data;
		this.left = null;
		this.right = null;
	}
}
class BinarySearchTree
{
	var root: TreeNode ? ;
	constructor()
	{
		this.root = null;
	}
	fun addNode(data: Int): Unit
	{
		val node: TreeNode = TreeNode(data);
		if (this.root == null)
		{
			this.root = node;
		}
		else
		{
			var find: TreeNode ? = this.root;
			// Add new node to proper position
			while (find != null)
			{
				if (find.data >= data)
				{
					if (find.left == null)
					{
						find.left = node;
						return;
					}
					else
					{
						// Visit left sub-tree
						find = find.left;
					}
				}
				else
				{
					if (find.right == null)
					{
						find.right = node;
						return;
					}
					else
					{
						// Visit right sub-tree
						find = find.right;
					}
				}
			}
		}
	}
	fun findLevelNode(node: TreeNode ? , 
                      record : HashMap < Int, MutableList < Int >>  , 
                      level : Int): Unit
	{
		if (node != null)
		{
			if (!record.containsKey(level))
			{
				record.put(level, mutableListOf < Int > ());
			}
			// Get level node
			record.getValue(level).add(node.data);
			this.findLevelNode(node.left, record, level + 1);
			this.findLevelNode(node.right, record, level + 1);
		}
	}
	fun printLevelLR(record: HashMap < Int, MutableList < Int >>  , 
                     level : Int): Unit
	{
		var i: Int = 0;
		while (i < record.getValue(level).size)
		{
			print("  " + record.getValue(level)[i]);
			i += 1;
		}
		print("\n");
	}
	fun printLevelRL(record: HashMap < Int, MutableList < Int >>  , 
                     level : Int): Unit
	{
		var i: Int = record.getValue(level).size - 1;
		while (i >= 0)
		{
			print("  " + record.getValue(level)[i]);
			i -= 1;
		}
		print("\n");
	}
	fun alternateLevel(): Unit
	{
		if (this.root != null)
		{
			val record: HashMap < Int, MutableList < Int >> = 
              HashMap < Int, MutableList < Int >> ();
			this.findLevelNode(this.root, record, 1);
			var i: Int = 1;
			var j: Int = record.count();
			while (i <= j)
			{
				if (i != j)
				{
					// Top level
					this.printLevelLR(record, i);
					// Bottom level
					this.printLevelRL(record, j);
					i += 1;
					j -= 1;
				}
				else
				{
					// Middle level
					this.printLevelLR(record, i);
					i += 1;
				}
			}
		}
	}
}
fun main(args: Array < String > ): Unit
{
	val tree: BinarySearchTree = BinarySearchTree();
	/*
	           70
	          /  \
	         /    \
	        60     80
	       / \    /  \
	      30  65 75   90
	     / \     / \   \
	    10  40  73  77  95
	*/
	tree.addNode(70);
	tree.addNode(60);
	tree.addNode(30);
	tree.addNode(65);
	tree.addNode(10);
	tree.addNode(40);
	tree.addNode(80);
	tree.addNode(75);
	tree.addNode(73);
	tree.addNode(77);
	tree.addNode(90);
	tree.addNode(95);
	tree.alternateLevel();
}

Output

  70
  95  77  73  40  10
  60  80
  90  75  65  30
Last updated on by Kalkicode




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