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Reverse queue using recursion

Here given code implementation process.

// C++ program for
// Reverse queue using recursion
#include <iostream>

#include <queue>

using namespace std;
// Display queue elements
// Here used one extra queue to store actual queue element
void display_queue(queue <int> & record)
{
	if (record.size() == 0)
	{
		//When queue is empty
		return;
	}
	queue <int> other;
	int data = 0;
	// Copy Queue elements into new queue
	while (record.size() > 0)
	{
		//Get front element
		data = record.front();
		other.push(data);
		record.pop();
	}
	// Display queue element
	while (other.size() > 0)
	{
		//Get front element
		data = other.front();
		cout << " " << data;
		other.pop();
		//Add element back to actual queue
		record.push(data);
	}
	cout << endl;
}
//Reverse a queue elements
void reverse_queue(queue <int> & record)
{
	if (record.size() == 0)
	{
		//When queue is empty
		return;
	}
	else
	{
		//Get front element
		int data = record.front();
		//Remove a element of queue
		record.pop();
		//Recursive execute function
		reverse_queue(record);
		//Add back to queue
		record.push(data);
	}
}
int main()
{
	//Define a queue of integer elements
	queue <int> record;
	//Add queue elements
	record.push(2);
	record.push(3);
	record.push(6);
	record.push(1);
	record.push(9);
	record.push(8);
	cout << "\n Before Reverse element : ";
	display_queue(record);
	reverse_queue(record);
	cout << "\n After Reverse element  : ";
	display_queue(record);
	return 0;
}

Output

 Before Reverse element :  2 3 6 1 9 8

 After Reverse element  :  8 9 1 6 3 2
//Java Program
//Reverse queue using recursion
import java.util.Queue;
import java.util.LinkedList;
class ReverseQueue
{
	public Queue < Integer > record;
	public ReverseQueue()
	{
		record = new LinkedList < > ();
	}
	// Display queue elements
	// Here used one extra queue to store actual queue element
	public void display_queue()
	{
		if (this.record.size() == 0)
		{
			//When queue is empty
			return;
		}
		Queue < Integer > other =  new LinkedList <> ();
		int data = 0;
		// Copy Queue elements into new queue
		while (this.record.size() > 0)
		{
			//Get front element
			data = this.record.peek();
			other.add(data);
			this.record.remove();
		}
		// Display queue element
		while (other.size() > 0)
		{
			//Get front element
			data = other.peek();
			System.out.print("  " + data);
			other.remove();
			//Add element back to actual queue
			this.record.add(data);
		}
		System.out.print("\n");
	}

	//Reverse a queue elements
	public void reverse_queue()
	{
		if (this.record.size() == 0)
		{
			//When queue is empty
			return;
		}
		else
		{
			//Get front element
			int data = this.record.peek();
			
			//Remove a element of queue
			this.record.remove();

			//Recursive execute function
			reverse_queue();
		   
			//Add back to queue
			this.record.add(data);
		}
	}
	public void add_record()
	{
		//Add Queue elements
		this.record.add(2);
		this.record.add(3);
		this.record.add(6);
		this.record.add(1);
		this.record.add(9);
		this.record.add(8);
	}
	public static void main(String[] args)
	{
		ReverseQueue obj = new ReverseQueue();
		obj.add_record();
		//Before
		System.out.print("\n Before Reverse element : ");
		obj.display_queue();

		obj.reverse_queue();
		//After
		System.out.print("\n After Reverse element  : ");
		obj.display_queue();
	}
}

Output

 Before Reverse element :   2  3  6  1  9  8

 After Reverse element  :   8  9  1  6  3  2
//Include namespace system
using System;
using System.Collections;
// Reverse queue using recursion
class ReverseQueue
{
	public Queue record = null;
	public ReverseQueue()
	{
		record = new Queue();
	}
	//Display queue elements
	public void display_queue()
	{
		if (this.record.Count == 0)
		{
			return;
		}
		// Display Queue Elements
		foreach(var element in this.record)
		{
			Console.Write("  {0}",element);
		}
	}
	//Reverse a queue elements
	public void reverse_queue()
	{
		if (record.Count == 0)
		{
			//When queue is empty
			return;
		}
		else
		{
			int data = (int) record.Peek();
			//Remove front element of queue
			this.record.Dequeue();
			reverse_queue();
			//append data into queue
			this.record.Enqueue(data);
		}
	}
	public void add_record()
	{
		//Add queue elements
		this.record.Enqueue(2);
		this.record.Enqueue(3);
		this.record.Enqueue(6);
		this.record.Enqueue(1);
		this.record.Enqueue(9);
		this.record.Enqueue(8);
	}
	public static void Main(String[] args)
	{
		ReverseQueue obj = new ReverseQueue();
		obj.add_record();
		//Before
		Console.Write("\n Before Reverse element : ");
		obj.display_queue();
		//Reverse Element
		obj.reverse_queue();
		//After
		Console.Write("\n After Reverse element  : ");
		obj.display_queue();
	}
}

Output

 Before Reverse element :   2  3  6  1  9  8
 After Reverse element  :   8  9  1  6  3  2
<?php
// Php Program
// Reverse queue using recursion
class ReverseQueue
{
    public $record;

    function __construct()
    {
        //Create a custom queue
        $this->record = array();
    }
    public function enqueue($data) 
    {
        //Add element at end of queue
        array_push($this->record,$data);
    }

    public function dequeue() 
    {

        // Check whether queue array is empty or not
        if (count($this->record) == 0) 
        {
            // When try of remove a element in empty queue
            echo ("Queue Empty");
            return;
        } 
        else 
        {

            array_shift($this->record);
        }
    }
    public function peek() {

        // Check whether queue array is empty or not
        if (count($this->record)==0) 
        {
            // When try of remove a element in empty queue
            echo ("Queue Empty");

        } else 
        {

            return $this->record[0];
        }
    }
    //Display queue elements
    public  function display_queue()
    {
        if (count($this->record) == 0)
        {
            return;
        }
        
        for ($i=0; $i < count($this->record) ; $i++) 
        { 
           echo " ".$this->record[$i];
        }
    }
    
    //Reverse a queue elements
    public  function reverse_queue()
    {
        if (count($this->record) == 0)
        {
            //When queue is empty
            return;
        }
        else
        {
            $data = $this->peek();

            //Remove front element of queue
            $this->dequeue();

            $this->reverse_queue();

            //append data into queue
            $this->enqueue($data);
        }
    }
    public  function add_record()
    {

        //Add queue elements
        $this->enqueue(2);
        $this->enqueue(3);
        $this->enqueue(6);
        $this->enqueue(1);
        $this->enqueue(9);
        $this->enqueue(8);

    }
}

function main()
{
    $obj = new ReverseQueue();
    $obj->add_record();
    echo "\n Before Queue element : ";
    $obj->display_queue();
    //Reverse Element
    $obj->reverse_queue();
    echo "\n After Queue element  : ";
    $obj->display_queue();
}
main();

Output

 Before Queue element :  2 3 6 1 9 8
 After Queue element  :  8 9 1 6 3 2
// Node JS program for
// Reverse queue using recursion
class ReverseQueue
{
	constructor()
	{
		this.record = [];
	}
	//Display queue elements
	display_queue()
	{
		if (this.record.length == 0)
		{
			return;
		}
		for (var i = 0; i < this.record.length; i++)
		{
			console.log(this.record[i]);
		}
	}
	peek()
	{
		if (this.record.length == 0)
		{
			return;
		}
		else
		{
			return this.record[0];
		}
	}
	dequeue()
	{
		if (this.record.length == 0)
		{
			//When queue is empty
			return;
		}
		else
		{
			this.record.shift();
		}
	}
	//Reverse a queue elements
	reverse_queue()
	{
		if (this.record.length == 0)
		{
			//When queue is empty
			return;
		}
		else
		{
			var data = this.peek();
			//Remove front element of queue
			this.dequeue();
			this.reverse_queue();
			//append data into queue
			this.record.push(data);
		}
	}
	add_record()
	{
		//Add queue elements
		this.record.push(2);
		this.record.push(3);
		this.record.push(6);
		this.record.push(1);
		this.record.push(9);
		this.record.push(8);
	}
}

function main()
{
	var obj = new ReverseQueue();
	obj.add_record();
	console.log("\n Before Reverse element : ");
	obj.display_queue();
	//Reverse Element
	obj.reverse_queue();
	console.log("\n After Reverse element  : ");
	obj.display_queue();
}
main();

Output

 Before Reverse element :
2
3
6
1
9
8

 After Reverse element  :
8
9
1
6
3
2
Last updated on by Kalkicode




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