Zeek_93_ArrayDeque.java

 

/*

--> An ArrayDeque (also known as an “Array Double Ended Queue”, pronounced as “ArrayDeck”)

--> ArrayDeque is a special kind of a growable array that allows us to

    add or remove an element from both sides.

--> An ArrayDeque implementation can be used as a Stack (Last-In-First-Out) or

     a Queue(First-In-First-Out).

Really Important

Insertion from Head:  offerFirst(e)  ----> also say addFirst();

Insertion from Tail:  offerLast(e)  ----> also say addLast();

........................................................................

Retrieval from Head:  peekFirst()    ----> also say getFirst();

Retrieval from Tail:  peekLast()    ----> also say getLast();

........................................................................

Removal from Head:    pollFirst()    ----> also say removeFirst();

Removal from Tail:    pollLast()    ----> also say removeLast();

*/

package com.company;

import java.util.*;

public class Zeek_93_ArrayDeque {

    public static void main(String[] args) {

       

        ArrayDeque <Integer> a1= new ArrayDeque();

       

        a1.add(5);

        a1.add(6);

        a1.add(4);

        a1.add(2);

       

        a1.offerFirst(19);

        a1.offerLast(34);

       

        System.out.println("First element of array is: "+a1.peekFirst());

        System.out.println("Last element of array is: "+a1.peekLast());

       

    }

}