**Java deque** is a two ended queue where elements can be added or removed from either ends. It is implemented by using the `java.util.Deque` interface which is also a subtype of the `java.util.Queue interface`. 

This means that you can use Java deque like a Java queue if ever needed.

# How to add an element in Deque

`java.util.Deque` provides 3 different functions for adding an element to a queue:

* **d.add(ElementToBeAdded):**   It adds an element to a queue at first available position from the start of the queue.

   
* **d.addFirst(ElementToBeAdded):** It adds an element to the start of a queue and shifts all the existing elements to the right by one position.

*  **d.addLast(ElementToBeAdded):** It adds an element to the end of a queue.

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## Example
This example adds elements using the functions mentioned above and then prints the queue.

import java.util.*; 
class example { 
   public static void main(String[] args) { 
      Deque<String> d = new LinkedList<String>(); 
      d.add("10");
      d.addFirst("5"); 
      d.addLast("15"); 
      System.out.println("My deque is: " + d); 
   }
}

# How to remove an element from Deque:

`java.util.Deque` provides 3 different functions for removing an element from a queue:
* **d.remove():**  It simply removes an element from the start of a queue. 
   
* **d.removeFirst():** This also removes an element from the start of a queue. 
*  **d.removeLast():** It removes an element from the end of a queue.

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## Example
This example adds elements using **Example 1's** functions and then removes an element using the **`d.removeLast()`** and **`d.removeFirst()`**  functions. You may replace d.removeFirst with **`d.remove()`** to verify the results.

import java.util.*; 
class example { 
   public static void main(String[] args) { 
      Deque<String> d = new LinkedList<String>(); 
      d.add("10");
      d.addFirst("5"); 
      d.addLast("15"); 
      System.out.println("My deque is: " + d); 

      d.removeLast(); 
      System.out.println("My deque after removing last element is: " + d);    

      d.removeFirst(); 
      System.out.println("My deque after removing first element is: " + d);          
   }
}

How to use a Java deque

Java deque is a two ended queue where elements can be added or removed from either ends. It is implemented by using the java.util.Deque interface which is also a subtype of the java.util.Queue interface. This means that you can use Java deque like a Java queue if ever needed. 

How to use a Java deque

How to insert or remove queue elements

How to add an element in Deque

Example

How to remove an element from Deque:

Example